Dp200 Workshop Manual

WORKSHOP MANUALDP200 SERIES FUEL INJECTION PUMP DDNX121(EN)

2006

(D) Kommen Sie nicht mit dem Hochdruckstrahl in Verbindung! Besonders nicht, wennDruckrohrleitung oder Dichtung geprft werden! Hochdruckflssigkeiten knnen tdlicheVerletzungen verursachen! Im Falle einer Berhrung mit der Haut, kontaktieren Siesofort einen Arzt. Bitte beachten Sie die Gesundheits-/und Sicherheitsunterlagen.

(E) Mantenga las manos y el cuerpo lejos del rociado del lquido, especialmente inyectores,tuberas y juntas de alta presin con fugas. La inyeccin de alta presin puede perforarla piel humana y producir una lesin fatal. En caso de que la inyeccin atraviese la piel,consiga atencin mdica inmediatamente. Vea la hoja de Datos de Sanidad ySeguridad.

(EN) Do not put your skin into the fuel jets under pressure, especially those due to pressurepipe or seal leaks. High pressure liquids can cause deadly injuries. In case of aninjection under the skin, contact a doctor immediately. Please refer to the health andsecurity fuel documents.

(F) Ne pas approcher les mains ni le corps des jets de liquides, particulirement ceuxprovenant des fuites de tuyaux et des joint soumis a la haute pression. Le liquide soushaute pression inject sous la peau peut causer des blessures mortelles. En casdinjection sous la peau, consulter immdiatement un mdecin. Se reporter a la fiche desant et de scurit du gazole.

(IT) Non esporre le mani o altre parti del corpo a getti di gasolio ad alta pressione,specialmente a quelli provenienti da tubi o paraolii. I getti di liquidi ad alta pressionepossono causare ferite anche mortali. In caso di iniezione sotto pelle contattareimmediatamente un medico. Fare riferimento alle schede di sicurezza del gasolio.

(NL) Zorg dat uw handen of andere lichaamsdelen niet in contact komen met vloeistofstralenonder hoge druk, met name bij een lek aan een leiding of dichting. Als de vloeistof onderhoge druk onder de huid terechtkomt, kan dit zelfs tot dodelijke verwondingen leiden. Alsde vloeistof onder de huid terechtkomt, onmiddellijk een arts raadplegen. Lees degezondheids- en veiligheidsfiche met betrekking tot de brandstof.

(P) No exponha a pele a jactos de combustvel sob presso, especialmente os devidos afugas de tubos de presso ou vedantes. Lquidos a alta presso podem causarferimentos mortais. No caso de injeco subcutnea, consulte imediatamente ummdico. Consulte por favor a documentao respeitante a sade e segurana decombustveis.

(D) Schutzbrille/Gesichtsschutz tragen.(E) sese proteccin para los ojos/la cara.(EN) Wear eye/face protection.(F) Porter un appareil de protection des yeux / du visage.(IT) Proteggersi gli occhi/la faccia.(NL) Veiligheidsbril/-masker gebruiken.(P) Use proteco da face/olhos.

(D) Von Zndquellen fernhalten - Nicht rauchen.(E) Conservar alejado de toda llama o fuente de chispas -No fumar.(EN) Keep away from sources of ignition - No smoking.(F) Conserver l'cart de toute flamme ou source d'tincelles - Ne pas fumer.(IT) Conservare lontano da fiamme e scintille - Non fumare.(NL) Ver van open vuur en ontstekingsbronnen houden Niet roken.(P) Mantenha afastado de fontes de ignio Proibido fumar.

(D) Geeignete Schutzhandschuhe tragen.(E) Usen guantes adecuados.(EN) Wear suitable gloves.(F) Porter des gants appropris.(IT) Usare guanti adatti.(NL) Aangepaste veiligheidshandschoenen dragen.(P) Use luvas apropriadas.

CONTENTS

Delphi Diesel Systems Ltd

Publication N: DDNX121(EN) Issue 2 of 09/2006 i

INTRODUCTION 1

DISMANTLING 2

COMPONENT INSPECTION AND RENEWAL 3

REASSEMBLY 4

TEST PROCEDURE 5

TOOLING, TORQUES & EVDS 6

BC - Boost Control

CA - Cold Advance

CP - Zero Backlash Drive

DCU - Diesel Control Unit

ESOS - Electric Shut-Off Solenoid

EVD - Exploded View Diagram

FIE - Fuel injection Equipment

HP - High Pressure

LLA - Light Load Advance

PECSA - Pressure End Cold Servo Advance

SECSA - Spring End Cold Servo Advance

SIN - Service Instruction Note

TP - Transfer Pressure

NOTATIONAL CONVENTIONS AND ABBREVIATIONS

ii

Produced by:

Delphi Diesel Systems Ltd.

Diesel Aftermarket

Spartan Close

Warwick

CV34 6AG Tel.: (44) (0)1926 472 900

UK Fax: (44) (0)1926 472 901

Delphi Diesel Systems Ltd

1 INTRODUCTION

1.1 The Pump ........................................................................................................................................................................7

1.2 General ............................................................................................................................................................................7

1.3 This Manual .....................................................................................................................................................................8

1.4 Equipment .......................................................................................................................................................................8

1.5 Replacement of Parts .....................................................................................................................................................8

1.6 Pump Name Plate ......................................................................................................................................................8 - 9

2 DISMANTLING

2.1 Preparation ....................................................................................................................................................................11

2.1.1 Cleaning and draining .......................................................................................................................................11

2.1.2 Mounting the pump ..........................................................................................................................................11

2.1.3 Removing sealing caps and locking wire ........................................................................................................11

2.1.4 Removing the drive hub (if fitted) ....................................................................................................................12

2.1.5 Measuring drive shaft end float .......................................................................................................................12

2.1.6 Measuring drive shaft radial play ....................................................................................................................12

2.2 Governor Cover, Control Levers & Link Assembly ....................................................................................................13

2.2.1 Removing the fuel return connections ............................................................................................................13

2.2.2 Removing the throttle lever stop screws, maximum fuel screw and torque control screw ......................13

2.2.3 Removing the throttle lever ..............................................................................................................................13

2.2.4 Removing the exhaust brake lever ..................................................................................................................14

2.2.5 Removing the electronic actuator throttle lever (rigid type) .........................................................................14

2.2.6 Removing the governor cover assembly .................................................................................................14 - 19

2.3 Dismantling the All-Speed Governor ..........................................................................................................................19

2.4 Removing the Control Bracket and Arm Assembly ...................................................................................................19

2.4.1 Removing the scroll link plate return spring ..................................................................................................19

2.4.2 Removing the governor control bracket assembly ........................................................................................20

2.4.3 Dismantling the governor control arm assembly ..........................................................................................20

2.4.4 Dismantling the governor control plate assembly for torque trimmer variant ..........................................20

2.5 High Pressure Outlets, End Plate Assembly, Electric Shut-off Solenoid (ESOS) & Transfer Pump ......................21

2.5.1 High pressure outlets ........................................................................................................................................21

2.5.2 Endplate assembly .....................................................................................................................................21 - 22

2.6 Electric Shut-off Solenoid (ESOS) ...............................................................................................................................22

2.7 Transfer Pump ...............................................................................................................................................................23

2.7.1 Removing the transfer pump components .....................................................................................................23

2.7.2 Slackening the transfer pump rotor .................................................................................................................23

2.8 Advance Device .....................................................................................................................................................23 - 24

2.8.1 Single piston design with 2 bolt cold advance ...............................................................................................24

2.8.2 Servo piston design with 2 bolt cold advance ........................................................................................25 - 26

2.8.3 Servo piston design with 4 bolt cold advance ........................................................................................26 - 27

2.8.4 Single piston design without cold advance ............................................................................................27 - 28

2.9 Removing the Head Locking Screws and Releasing the Hydraulic Head ...............................................................28

2.9.1 Head locking screws .........................................................................................................................................28

2.9.2 Removing and dismantling the LLA ................................................................................................................28

2.9.3 Removing and dismantling the latch valve ....................................................................................................29

2.9.4 Removing the hydraulic head ..........................................................................................................................29

2.10 Drive Shaft .....................................................................................................................................................................30

2.10.1 Dismantling the zero backlash drive assembly .......................................................................................30 - 31

2.10.2 Dismantling the splined drive assembly .........................................................................................................31

CONTENTS

iii

2.11 Dismantling the Hydraulic Head - Check and Cheek Plate Designs .........................................................................31

2.11.1 Releasing the drive plate screws .....................................................................................................................31

2.11.2 Dismantling the rotor components ..................................................................................................................32

2.11.3 Removing the lower check or cheek plate ......................................................................................................32

2.11.4 Reverse thrust weight assembly ......................................................................................................................32

2.11.5 Lock-shaft timing ...............................................................................................................................................33

2.11.6 Removing the drive shaft seal/s .......................................................................................................................33

3 COMPONENT INSPECTION AND RENEWAL

3.1 Cleaning .........................................................................................................................................................................35

3.2 General ..........................................................................................................................................................................35

3.2.1 Mated and matched assemblies ......................................................................................................................35

3.2.2 Examination and replacement .........................................................................................................................35

3.2.3 Seals ...................................................................................................................................................................35

3.3 Details ............................................................................................................................................................................35

3.3.1 Hydraulic head rotor .........................................................................................................................................35

3.3.2 Hydraulic head plungers ...................................................................................................................................35

3.3.3 Cam ring and scroll plates ................................................................................................................................35

3.3.4 Rollers and shoes ..............................................................................................................................................35

3.3.5 Transfer pump ............................................................................................................................................35 - 36

3.3.6 Endplate .............................................................................................................................................................36

3.3.7 Control valves ....................................................................................................................................................36

3.3.8 Delivery valves and cambox pressurising valves ..........................................................................................36

3.3.9 High pressure outlet pressurising valves ........................................................................................................36

3.3.10 Springs ...............................................................................................................................................................36

3.3.11 Fittings and threads ...........................................................................................................................................36

3.3.12 Linkages .............................................................................................................................................................36

3.3.13 Control shafts .....................................................................................................................................................36

3.3.14 Drive shafts and associated components .......................................................................................................36

3.3.15 Advance device ..................................................................................................................................................36

3.3.16 Levers and external controls ............................................................................................................................36

3.3.17 Pump housing ....................................................................................................................................................36

3.3.18 Governor control cover .....................................................................................................................................36

3.3.19 Orifices ...............................................................................................................................................................36

3.3.20 Electric shut-off solenoid ..................................................................................................................................36

3.3.21 Wax motor ..........................................................................................................................................................37

4 REASSEMBLY

4.1 Preparation ....................................................................................................................................................................39

4.2 Assembling the Hydraulic Head ..................................................................................................................................39

4.2.1 Rotor plug ...................................................................................................................................................39 - 40

4.2.2 Drive plate, rollers, shoes and retaining plates .......................................................................................40 - 42

4.3 Drive Shaft .....................................................................................................................................................................42

4.3.1 Zero backlash and splined drive with cheek plates ................................................................................42 - 45

4.3.2 Spline drive with check plate head and rotor .........................................................................................45 - 46

CONTENTS

iv

CONTENTS

v

4.4 Securing the Hydraulic Head and Checking Drive Shaft End Float and Radial Play ..............................................46

4.4.1 Replacing the drive shaft seal/s .......................................................................................................................46

4.4.2 Securing the drive shaft ....................................................................................................................................46

4.4.3 Aligning the hydraulic head .............................................................................................................................47

4.4.4 Checking drive shaft end float ..........................................................................................................................47

4.4.5 Checking drive shaft radial play .......................................................................................................................47

4.4.6 Cam advance screw ..........................................................................................................................................48

4.4.7 Fitting the head locking screws, light load advance valve and latch valves ........................................48 - 49

4.5 Advance Device .............................................................................................................................................................49

4.5.1 Single piston design ..................................................................................................................................50 - 51

4.5.2 Servo piston designs .................................................................................................................................52 - 55

4.5.3 2 Bolt cold advance fitted to single piston design ..................................................................................55 - 56

4.5.4 2 bolt cold advance fited to servo piston design ...........................................................................................56

4.5.5 4 bolt cold advance fitted to servo piston design ..........................................................................................57

4.6 Transfer Pump and End Plate Assembly ...........................................................................................................................57

4.6.1 Transfer pump ...................................................................................................................................................57 - 58

4.6.2 Endplate assembly ...........................................................................................................................................58 - 60

4.7 ESOS and High Pressure Outlets .......................................................................................................................................61

4.7.1 ESOS or blanking plug ............................................................................................................................................61

4.7.2 High pressure outlets and clamp plate ..........................................................................................................61 - 62

4.8 Governor Linkage, Control Bracket and Cover .................................................................................................................62

4.8.1 Governor linkage ......................................................................................................................................................62

4.8.2 Fitting the governor assembly to the pump .........................................................................................................62

4.8.3 Fitting the scroll link plate return spring ...............................................................................................................63

4.8.4 Setting the governor link length ............................................................................................................................63

4.8.5 Fitting the governor assembly for torue trimmer variant ........................................................................63 - 65

4.9 Assembling the Governor Cover .......................................................................................................................................65

4.9.1 Governor cover only ........................................................................................................................................65 - 66

4.9.2 Governor cover fitted with hydraulic excess fuel .........................................................................................66 - 67

4.9.3 Governor cover fitted with boost control only ..............................................................................................68 - 70

4.9.4 Governor cover fitted with torque control and torque control plus boost control ..................................71 - 75

4.9.5 Governor cover fitted with electronic actuator .............................................................................................75 - 77

4.10 Governor Cover External Components .............................................................................................................................77

4.10.1 Fitting backleak components ..................................................................................................................................77

4.10.2 Fitting and aligning external levers .......................................................................................................................78

4.10.3 Control stop screws and plugs ...............................................................................................................................79

4.11 Shaft Locking Screw, Drain Plug and Cam Ring Access Plug ........................................................................................80

4.11.1 Shaft locking screw ..................................................................................................................................................80

4.11.2 Drain plug ..................................................................................................................................................................80

4.11.3 Cover ..........................................................................................................................................................................80

4.11.4 Cam ring access plug ..............................................................................................................................................80

4.12 Drive Hub ..............................................................................................................................................................................80

4.13 Leak Testing ..........................................................................................................................................................................80

4.14 Storage ..................................................................................................................................................................................81

4.14.1 New pumps ...............................................................................................................................................................81

4.14.2 Overhauled pumps ..................................................................................................................................................81

4.14.3 Storage conditions ...................................................................................................................................................81

CONTENTS

vi

5 TEST PROCEDURE

5.1 Preparation ....................................................................................................................................................................83

5.1.1 Leak testing ........................................................................................................................................................83

5.1.2 Test machine ......................................................................................................................................................83

5.1.3 Test machine drive ............................................................................................................................................83

5.1.4 Test conditions ...........................................................................................................................................83 - 84

5.1.5 Connecting fuel lines ........................................................................................................................................84

5.1.6 Machine test procedure .............................................................................................................................84 - 85

5.1.7 Transfer pressure measurement and initial setting .......................................................................................85

5.1.8 Cambox pressure measurement ......................................................................................................................85

5.1.9 Adjustments to be pre-set .........................................................................................................................86 - 87

5.2 Test Procedure ...............................................................................................................................................................87

5.2.1 Priming ...............................................................................................................................................................87

5.2.2 Checking and setting transfer pressure ...........................................................................................................88

5.2.3 Cambox pressure and backleakage checks .............................................................................................88 - 89

5.2.4 Speed advance setting ......................................................................................................................................89

5.2.5 Cold advance ..............................................................................................................................................89 - 90

5.2.6 Light load advance valve setting .....................................................................................................................90

5.2.7 Boost control with torque trimmer ..................................................................................................................91

5.2.8 Maximum fuel delivery setting .................................................................................................................91 - 92

5.2.9 Latch valve .........................................................................................................................................................93

5.2.10 Governor setting and testing ...........................................................................................................................93

5.2.11 Torque screw setting .........................................................................................................................................93

5.2.12 Idle setting ..........................................................................................................................................................94

5.2.13 Shut-off control check .......................................................................................................................................94

5.3 Timing ............................................................................................................................................................................94

5.3.1 General ........................................................................................................................................................94 - 95

5.3.2 Keyed drive shafts .....................................................................................................................................95 - 96

5.3.3 Keyless drive shafts ...................................................................................................................................96 - 99

5.4 Leakage Testing .............................................................................................................................................................99

6 TOOLING, TORQUES & EVDS

6.1 Tooling ................................................................................................................................................................101 - 103

6.2 Torque values .....................................................................................................................................................104 - 108

6.3 Exploded view diagram ....................................................................................................................................109 - 119

INTRODUCTION

1 - 7

1.1 THE PUMP

The DP200 distributor-type fuel injection pump is a

compact, self-contained unit that is suitable for

direct injection engines of up to 33 BHP per cylinder

and with two, three, four or six cylinders. It is

primarily intended for the industrial and agricultural

markets.

All internal working parts are lubricated by fuel oil

and the pump housing is maintained at an internal

pressure that prevents the ingress of external dirt or

other foreign matter.

Standard features include automatic air venting,

compensation for variations in fuel viscosity.

It can be fitted with a range of options to produce

performances to match a wide variety of engine

requirements, including boost-pressure control of

fuel delivery level for turbocharged engines, and

load or speed dependent timing control.

Due to the complexity of this product, the need for

highly-trained personnel, and a high level of

investment in equipment and workshop resources,

together with the need for up-to-date Technical

Information, it can only be tested or serviced by

Delphi Authorised Distributors.

It has been developed from the well-known range of

DPA and DPS injection pumps and is the result of the

Delphi policy of continued improvement of products

to meet the demands of new legislation and

operational requirements.

1.2 GENERAL

Fuel pumps may require off-engine workshop

attention for two main reasons:

(a) Investigation of a specific fault in engine

performance, which may only require partial

dismantling.

(b) A complete overhaul e.g. at the same time as a

major engine overhaul.

A full performance test is recommended, both

before and after any level of attention, as many

aspects of pump performance are interrelated.

DP200 PUMP

INTRODUCTION

1 - 8

1.3 THIS MANUAL

The Dismantling, Reassembly and Testing Sectionsare laid out on a step-by-step basis, with eachaction accompanied by an illustration showing thecomponent(s) involved and, where applicable,its/their positions on the pump. The Manual is notbased on any one specification, but covers pumpfeatures which have been included up to the time ofpublication. For the purposes of illustration, morethan one pump specification has been used.

The pumps illustrated are for clockwise rotation(when viewed from the drive end); anticlockwisepumps will have items such as the maximum fuelscrew, and the boost control fitted on the sideopposite to that shown. In addition, the advancedevice will operate in the opposite mode.

Instructions for both full and partial dismantling ofthe pump are included e.g. total dismantling andexamination of all components other than those thatare factory-sealed units and removal of the hydraulichead and rotor only.

All the necessary tools are listed in Section 6.Special tools are identified by part number andstandard tools by type and size.

1.4 EQUIPMENT

Any tools, both standard and special-purpose, usedfor the servicing or repair of fuel injection equipment(FIE) must be reserved solely for use on FIE. Worn ordamaged tools can cause damage to criticalcomponents, as well as being a safety hazard.

The working area must be scrupulously clean andshould be in a room separated from any otheractivity; the ingress of dust and dirt, airborne orotherwise, must be prevented.

The minimum facilities required are:

1. A bench covered in non-rusting metal or industrial-grade linoleum and fitted with an engineers vicewith a jaw size of 100 mm (4 in). The vice jaws mustbe faced with either soft metal or fibre pads.

2. An adjustable pump-mounting device such as theHydraclamp, fitted with an appropriate adaptorplate.

3. Easily cleaned compartmented trays for separatestorage of dismantled components such as Part No.60620197.

4. All the necessary tools as listed in Section 6 of thisManual.

5. A low-pressure washing facility using a suitable,approved, cleaning fluid (not water or water-based)to clean pumps externally prior to dismantling.Cleaning must be carried out in a place separatedfrom the clean area.

6. A tank large enough to accommodate a completepump and filled with clean test oil, near to a sourceof clean, dry, variable pressure compressed air forcarrying out leakage tests.

7. Supplies of clean, lint-free (non-fluffy) cloths forcleaning and drying components. Cotton wastemust never be used.

8. A pump test machine that conforms to ISO 4008.

9. Adequate storage facilities for pumps, tools and testequipment, with separate areas for pumps beforeand after repair.

Note: All cleaning tanks, workshop and test facilities and

fluids must conform to any Fire Prevention or Health

and Safety Regulations in force at the time of use.

1.5 REPLACEMENT OF PARTS

All gaskets and seals must be replaced during

reassembly. However, in the event of partial

dismantling, only those seals that have been

disturbed need replacement, unless leaks from

elsewhere are detected during testing prior to

dismantling.

If any part of a mated assembly is worn or

damaged, the whole assembly must be replaced.

Any component showing signs of corrosion or water

ingress, cracks or distortion must be replaced.

Only service parts supplied by Delphi Diesel Systems

Aftermarket Operations may be used as

replacements. Parts supplied from alternative

sources may appear to be externally similar and may

carry the same part numbers as the genuine item but

may be inferior in material specification or finish and

lead to malfunction or premature failure.

1.6 PUMP NAME PLATE

The number stamped on the type-plate attached to

the pump housing identifies the type and model of

the pump. Pumps with identical build but with

different settings, dependent upon engine

application, are further identified by the setting code

stamped beneath the serial number.

A typical Despatch Number could be as shown in

Fig. 1.

INTRODUCTION

1 - 9

Note 1: The pumps shown in the illustrations do not

necessarily represent any one specification, but

are used to show particular features.

Note 2: As components are removed, inspect them and

put those considered unfit for further service to

one side for replacement; place those which

are fit for further service into a clean

compartmented tray. (Trays available through

Delphi Diesel Systems Aftermarket Operations,

Service Operations Department.) A guide to

areas of possible wear or damage appears in

Section 3 (Component Inspection & Renewal).

C 89 2 0 A 06 0 L

If the name plate has been painted over, special care is needed when removing the paint to avoid erasure of the

information. Use a small quantity of proprietary paint-stripper, carefully observing the manufacturers instructions.

Marketing Code:

C = Spain

No letter = UK

Product Type (DP200)

Suffix letter -

Denotes the type of

ESOS fitted.

See SIN DT294

Change to the individual

specification affecting parts

interchangeability, but not fit or

function of pump.

Individual features

number.

Design change letter -

Has no significance at the

time of publication of this

manual

No. of delivery outlets:

0, 3 & 5 = 4 cyl.

1 & 4 = 6 cyl.

2 = 3 cyl.

6 - 9 to be allocated

Design Source:

0 = USA 1 = Korea

2&3 = UK 4 = France

5 = Spain 6 = Brazil

7 = India 8 = Poland

9 = Japan

Fig. 1 Explanation of Despatch Number

INTRODUCTION

1 - 10

DISMANTLING

2 - 11

A980

A950

2.1 PREPARATION

A list of all tools required to dismantle and

reassemble the pump is in Section 6.

2.1.1 Cleaning and draining

Externally clean the pump. Remove the drain plug

(1) on the side of the pump and drain any fuel oil

remaining in the housing.

If the pump is to have a possible defect rectified, or

is subject to a warranty assessment, a preliminary

test on the test machine may be required. In this

case, externally clean the pump as above but drain

the fuel oil into a clean container for possible

subsequent analysis.

If the pump has not seized, and it is to be tested prior

to dismantling, examination will first be necessary to

determine if dirt or water ingress has occurred, so as

to avoid contamination of the test fuel and possible

damage to the test equipment.

If it is not possible to see through the drain plug

hole, remove the advance device (see Section 2.8)

and closely examine the components for signs of

corrosion or metal particles. If there is no

contamination, refit the advance device, using a new

gasket, O-rings on the head locating fitting, and a

new sealing washer under the dome nut. Tighten

the head locating fitting and the dome nut to their

respective torques and proceed with the test.

2.1.2 Mounting the pump

Mount the pump on a Hydraclamp using a Hartridge

mounting plate (1) with a suitable adaptor ring (2).

Align the pump with its axis horizontal and the

governor cover uppermost.

2.1.3 Removing sealing caps and locking wire

Remove any shrink sleeving, tamperproof caps or

locking wire from adjustment screws.

1

1

2

DISMANTLING

2 - 12

A952

A1005

2.1.4 Removing the drive hub (if fitted)

Restrain the drive hub (1) with the special tool (2).

Slacken the drive hub nut and spring washer just

sufficiently to allow release of the hub.

Use a suitable extractor to release the hub from the

drive shaft taper.

2.1.5 Measuring drive shaft end float

Note: To assess the condition of components subjectedto end-thrust, end-float must be measured priorto dismantling. The pump and gauge must beclamped to an assembly plate mounted in a viceor on a Hydraclamp.

Fit the appropriate adaptor (4) to the drive shaftthread. Screw in the dial gauge holder (3), and fit thegauge (2). Adjust the gauge pin to contact themounting plate adaptor ring at (1). Push the driveshaft inwards and set the dial gauge to zero. Pull thedrive shaft outwards and note the maximum gaugereading.

End-float should be 0.05 mm to 0.2 mm. If themaximum is exceeded, examine the housing thrust-faces during dismantling. If no significant wear ordamage is apparent, requiring replacement of thepump housing, correct the end-float by the use ofalternative shims during reassembly.

2.1.6 Measuring drive shaft radial play

Note: In order to assess the condition of the bearing anddrive shaft, radial play must be measured prior todismantling.

With the pump and gauge (1) mounted rigidlyrelative to each other, adjust the gauge pin to bear (atright angles) against the parallel section (4) of thedrive shaft. Note that this section is very short,therefore a fine tip will be required on the gauge pin.Push the shaft radially towards the gauge and set thegauge to zero.

Pull the shaft radially to the opposite extreme andrecord the gauge movement. Repeat the readingswith the gauge repositioned as shown at (2) and (3).Do not rotate the drive shaft. Reject the housing ifthe maximum play or the difference between themeasurements exceed the figures below.

Drive type Max. play Max. Difference

Belt 0.22 mm 0.1 mm

Gear or hub 0.27 mm 0.2 mm

1

2

34

1

23

4

A986

2

1

DISMANTLING

2 - 13

A953

A953

A1006

A1007

2.2 GOVERNOR COVER, CONTROL LEVERS &LINK ASSEMBLY

2.2.1 Removing the fuel return connections

Note: Fuel return arrangements will vary, dependent

upon the pump specification.

Unscrew and remove the connections (1) and (2)

fitted to the cover. If there is a bleed screw fitted at

position (3), unscrew and remove it. Discard the

sealing washers.

If a boost control device is fitted, unscrew the tube

nut (6) and remove the drain pipe (7); discard the

rubber olive (5) and the two sealing washers (4).

2.2.2 Removing the throttle lever stop screws,maximum fuel screw, and torque control screw

Loosen the lock nuts on the idling stop screw (1),

maximum speed stop screw (2), and torque screw

(5), and remove the screws and washers. Discard

any rubber sealing washers. Slacken and remove

the blanking plug (4) on the side of the governor

cover opposite to the maximum fuel stop (or boost

control device). Discard any sealing washer.

Note: For pumps fitted with boost control, maximum

fuel adjustment is incorporated within the boost

control device (6).

If the pump is not fitted with a boost-control, remove

the maximum fuel stop screw (3); discard the rubber

sealing washer.

2.2.3 Removing the throttle lever

2.2.3.1 Rigid type

Slacken, remove and discard the self-locking nut

(1); remove washer (2), large washer (3), spring

(4), spacer (5), spring retainer (6), throttle lever

(7), and dust cap (8).

A1261

A978

A1003

1 2 3 4

5

7

6

1 2 3

5

1

2

3

4

5

6

7

8

1 2 3 4 5 6 7 82.2.3.2 Break-back type

Slacken, remove and discard the self-locking nut

(1); remove washer (2), upper spring retainer (3),

spring (4), lower spring retainer (5), throttle lever

(6), break-back lever (7), and dust cover (8).

A1002

4

6

DISMANTLING

2 - 14

A954

A1048

A485a

2.2.4 Removing the exhaust brake lever

Slacken and remove the screw (1), shakeproof

washer (2) and flat washer (3). Lift the lever (4)

and release the tension of the spring (5). Remove

the lever, spring and dust cover (6).

A1256

1

2

3

4

5

6

2.2.5 Removing the electronic actuator throttle lever(rigid type)

Slacken and remove the bolt (558) and washers (559

and (560).

2.2.6 Removing the governor cover assembly

2.2.6.1 Governor cover only

Push the exhaust brake shaft (2) and the throttle

shaft (3) down into the cover. Remove the four

Torx screws at (1), (4), (5), and (6).

Lift off the cover and pull the throttle shaft (3) out

of its bore. Remove and discard the trapped

O-ring (1) from the sealing face of the cover.

Remove the exhaust brake shaft (2) and discard

its O-ring.

2.2.6.2 Governor covers fitted with hydraulic excess fuel

Using suitable circlip pliers, remove the internal

circlip (810) from the governor cover. Lever out

the closing plug (811) and remove and discard

the O-ring (812).

Note: At the later stage (depending on which

other features are fitted) when removing the

governor cover, the hydraulic excess fuel device

has to be disengaged.

Grip the governor cover firmly and hold the

excess fuel piston (813) with the thumb so as to

disengage the fork in the control bracket from the

excess fuel pin (819). Lift the governor

sufficiently to release the excess fuel pin from the

fork and then release the excess fuel piston.

Remove the hydraulic excess fuel piston.

From inside the governor cover, use the excess

fuel piston to push out the excess fuel assembly.

Separate the sleeve (814) and discard the O-ring

(815). Remove the external e-clip (816), spring

(817) and pin guide (818) from the excess fuel pin

(819).

813

814

815

816

817

818

819

A562a

1 2 34

5

6

EVD15

DISMANTLING

2 - 15

A955

A788

A787

A568

2.2.6.3 Governors covers fitted with boost control only

a) Removing the cover

Slacken and remove the cover plug (4); remove

and discard the plug O-ring.

Note: Take care when releasing the plug as it will

be under pressure from the pre-load spring (if

fitted).

Remove the shim(s) from the plug and the pre-

load spring from within the cover (2), if fitted.

Remove the two securing screws (1) and (3) and

remove the cover.

Note: Securing screws (1) and (3) and plug (4)

may be of the temper resistant design. To

remove these, a special tamper resist Torx bit

will be required. See Section 6.

b) Removing the diaphragm

Remove the diaphragm assembly (1); lift out the

spring plate (2), control springs (3), shim (4) and

fuel control rod (5).

1

2 3

4

1 2 3 4 5

c) Removing the fuel adjustment screw

Note: Other than for removal of the adjusting

screw, do not dismantle the diaphragm

assembly; if the diaphragm requires

replacement, the whole assembly must be

replaced.

Hold the nut (2) with a spanner; use an Allen key

to remove the fuel adjustment screw (1) from the

adjustment screw body. Carefully lever out and

discard the O-ring (3) from its recess in the rear of

the diaphragm assembly.

1 2 3

1

2d) Removing the diaphragm stroke adjustment

screw.

Unscrew and remove the diaphragm stroke

adjustment screw (1) from the screw body (2).

Remove and discard the O-ring from the

adjustment screw.

DISMANTLING

2 - 16

A1257

A1469

A1465

A1466

e) Removing the boost control housing

Use the special tool to unscrew and remove the

stroke adjustment screw body (1).

Note: As the adjustment screw body is

unscrewed, check that the Eslok patch on the

thread still creates a tight fit in the governor

cover thread. If it is not, the body must be

discarded.

Remove the shim(s) (2). Detach the housing (3);

carefully remove and discard the O-ring (5).

Check the spring pin (4) for damage; if necessary,

replace it.2

1

3

4

5

f) Removing the cover

Hold the governor control cover as shown; very

carefully lift it just enough to expose the

locating dowel pin (1) (if fitted).

2.2.6.4 Governor cover fitted with Torque Control and

Torque Control plus Boost Control

Remove pressure end plug circlip (1).1

a) Spring end components

If fitted, remove the plastic sealing plug in the

preload plug (1) with a pointed tool. Unscrew and

remove the plug, using the appropriate size of

Allen key, and discard the O-ring (3). Remove the

large spring (4), the spring plate (5) (if fitted), and

the small spring (6) (if fitted). Remove shim (2)

from inside preload plug.

Note 1: The preload plug fitted to later pumps

may be chamfered at its outer end, to prevent

unauthorised tampering.

Note 2: It may be necessary to re-position the

pump on the Hydraclamp mounting plate to gain

access to the preload plug.

A1467

1

1

1 23

45

6

DISMANTLING

2 - 17

A1473

A1477

b) Removal of the governor control cover

If no boost control is fitted, the cam follower will

be pivoted on a spindle, which is formed as a

part of a pivot plug screwed into the governor

control cover (1). A plastic tamper proof plug will

be fitted into the hexagon hole in the plug and

must be removed for fitment of the appropriate

Allen key. If the pivot-plug is to be removed,

slacken it by no more than one turn before

removal of the governor control cover (to avoid

the risk of damage to internal components).

c) Removal of the boost control cover and

diaphragm

Remove any tamperproof seal(s) from the boost

control cover fixing screws (3) and (6), and the

preload spring plug (4). Slacken and remove the

plug; discard the O-ring (7). Remove the preload

spring (9) and remove the shim (8) from the plug.

Note the position of the air inlet connection (2) on

the boost control cover relative to the fuel

backleak return connection (1). Slacken and

remove the two cover fixing screws and their flat

washers.

Caution: The cover (5) will be lifted up under theaction of the diaphragm return spring as thescrews are loosened.

Remove the cover and the diaphragm assembly(1).

If fitted, remove the shim from within the cupin the lower face of the diaphragm assembly.

Note 1: Do not dismantle the diaphragmassembly. If any part of it is worn or damaged,the whole assembly must be replaced.

Note 2: The spring (2), spring seat (3), andspindle (4), cannot be lifted out at this stage, asthey are retained by the cam follower and acirclip within the governor cover.

d) Removing the governor cover

Push the exhaust brake shaft (2) and the throttleshaft (3) down into the cover. Remove the fourTorx screws at (1), (4), (5), and (6).

Lift and rotate the cover off towards the torquetrimmer side, and pull the throttle shaft (3) out ofits bore. Remove and discard the trapped O-ring (7) from the sealing face of the cover.Remove the exhaust brake shaft (2) and discardits O-ring.

Note: If the control cover is lifted too far, thecarriage angle plate may become distorted; ifresistance is felt, lower it and move it furtheraway, then lift it again.

A1476

A1456

A1475

4

7

8

9

3

2

4

6

5

1

3

2 4

1

A1048 A1260

32 4

1

3

2

5

6

7

1

DISMANTLING

2 - 18

A1470

A1471

A1472

e) Removing the governor main spring

Slide the cover away (in the direction of the

torque trimmer) until the angle plate (1) is no

longer in the recess (2). Remove the governor

main spring (3) from the throttle shaft link, noting

the hole into which it is fitted. Lift off the control

cover and discard the trapped O-ring (4). Discard

the small transfer gallery O-ring that is in the

housing recess below the small hole (5).

1

23

4

5

f) Removing the piston and the pressure end plug

Tip out the torque trimmer cam (1), and the

piston (2). Use a suitable piece of soft metal or

plastic rod to push the plug (4) out of the cover:

discard the O-ring (3).

1

23

4

A1473

1

2

3

6

2

4

5

g) Removing the cam follower and its pivot

Remove the small circlip (2) and the cam follower

(6) from the spindle (5). Remove the washer (4)

(not visible) from the spindle.

If no boost control is fitted to the governor cover

and the cam follower is carried on a pivot plug,

remove the small circlip (2) and the cam follower.

Unscrew and remove the pivot plug (1); remove

and discard the O-ring (3).

DISMANTLING

2 - 19

DT237/2 fig 1

A958

A959

2.2.6.5 Governor cover fitted with Electronic Actuator

a) Removing the governor cover

Remove the four fixing screws from the governor

cover and gently lift the cover away from the

housing.

Disengage the governor spring, taking note of the

throttle link hole number.

Remove the lever (565) and discard the O-ring

(564).

Remove and discard the circlip (569) from the end

of the actuator shaft. (Later designs use a Nyloc

nut.)

Remove the lever (568) and washers (566).

b) Removing the Actuator

To remove the actuator (553) from the controlcover it is necessary to use a pair of mole-grips, as the screws (551) securing the unit arefitted with tamperproof steel balls (552) andtamper-evident washers (550).

Grip the washer (550) and rotate it in an anti-clockwise direction; this will loosen the washerand at the same time slacken the screw.

Discard the screw, the ball and the tamper-evident washer.

Carefully remove the actuator from the controlcover and then remove and discard the O-rings(557).

2.3 DISMANTLING THE ALL-SPEED GOVERNOR

Detach the governor main spring (5) from the idling

spring peg (1). Remove the peg, idling spring (2) and

pivot ball washer (3) from the governor arm (4).

Remove the main spring from the throttle shaft link

(6).

Remove and discard the two O-rings (7) and (8) from

the throttle shaft.

Note: Early pumps had a 3 hole link plate. A note must be

made of which hole is used to locate the spring. The

appropriate Service Test Plan will confirm the correct

hole to use.

2.4 REMOVING THE CONTROL BRACKET ANDARM ASSEMBLY

2.4.1 Removing the scroll link plate return spring

Push the scroll link plate (3), to compress the spring

and expose the end (5) of the spring pin; grip the end

of the pin, release the scroll link plate and pull the pin

away from the spring stop (2). Tip the shouldered

end of the pin upwards, to clear the spring stop and

carefully release and remove the pin and spring (4).

Warning

Cover the pin and spring with a non-fluffy

cloth in case it is released prematurely,

allowing it to be ejected at speed.

1 2 3 4 5 6 7 8

1 23

45

DISMANTLING

2 - 20

A1049

A961

Note: If it is difficult to grip the pin, carefully slacken the

spring stop screw (1) and allow the stop to swing

away from the pin, again taking care to avoid

rapid ejection of the pin.

1 2 3 4

56789

2.4.2 Removing the governor control bracket assembly

Straighten the ears of the two tab washers (2) and

(9). Slacken and remove the control plate screws (3),

(4), (6), and (8). Lift out the bracket (7), together with

the control arm assembly (1) and the metering valve

(5), from the pump housing.

Discard the tab washers.

Note: Screws 3 & 8 are of different lengths.

2.4.3 Dismantling the governor control arm assembly

Unscrew and remove the linkage lock nut (1) and

adjusting nut (2). Remove the pivot ball washer (3).

Withdraw the linkage hook (9), with the fibre washer

(4) and spring (6) from the governor control arm (5);

remove the spring retainer (7), and metering valve

assembly (8) from the linkage hook.

2.4.4 Dismantling the governor control plate assemblyfor torque trimmer variant

2.4.4.1 Removing the delivery adjusting screw

To remove the adjustment screw (1) from the

scroll link carriage assembly, use either the

special adjustment tool or an Allen screw with a

suitably sized hexagon socket. Rotate the screw

anti-clockwise to disengage it from the scroll link

(4). Discard the retaining clip (2).

Lift the screw to disengage the retaining clip

from the angle plate (3).

1 2 3 4 5 6 7 8 9

A1492

32

1

4

DISMANTLING

2 - 21

A962

A963

2.4.4.2 Removing the angle plate

To remove the angle plate (1), rotate it anti-

clockwise until it can be lifted up between the

arms (2) and (3) of the scroll link plate as shown.

A985b4

3

2

1

5

6

7

8

1

2

3

4

2.5 HIGH PRESSURE OUTLETS, END PLATEASSEMBLY, ELECTRIC SHUT-OFFSOLENOID (ESOS) & TRANSFER PUMP

2.5.1 High pressure outlets

Remove all the nuts (1), (2), (4), and (5) securing the

clamping plate (3) to the outlet connections, and

remove the plate.

If fitted, remove the four support plate screws at

position (6) and (8) and the pump-to-engine support

bracket (7).

Unscrew and remove each high pressure outlet,

using a long-reach socket. Remove and discard the

seating washer from the bottom of each outlet bore.

The high pressure outlets may be pressurising

valves which are factory-sealed units and cannot be

serviced. Alternatively the outlets may contain

delivery valves which must be retained in their

matched seat / valve pairs.

Remove the delivery valves, delivery valve springs

and pegs.

Delivery valve holders must be discarded.

2.5.2 Endplate assembly

2.5.2.1 Removing the endplate assembly

If fitted, unscrew and remove the accumulator

(7); discard the O-rings (5) and (6).

Slacken, but do not remove, the fuel inlet

connection (1). Slacken and remove the four

endplate screws (2), and (4) and remove the

endplate assembly (3) complete. EVD017

56

7

1

2

3A493A

DISMANTLING

2 - 22

2.5.2.2 Dismantling the end plate assembly

a) Viscosity compensating design

Remove the fuel inlet connection (1) and discard

the O-ring (2). Tip out the filter (3). Remove and

discard the adjuster (4) and the O-ring (on current

designs).

Screw the extractor (13) into the regulating

sleeve (6) and pull the sleeve out of the end plate.

Remove the piston retainer (10), the piston (8),

and the regulating spring (5); remove and discard

the O-ring (9) from the groove (7). Tip out the

sleeve retaining spring (11) and the spring seat

washer (12).

Note: The piston, sleeve and adjuster are

matched and are not interchangeable.

Remove the sandwich plate (14).

Note: If damaged carefully remove the

sandwich plate locating pin from the end plate

using a long nose pair of pliers. Note the

particular hole in the endplate too which it is

fitted. Incorrect fitting will effect transfer pump

operation.

A1284A1258

1

2

3

4

5 6

7

b) Non-viscosity compensating design

Remove the fuel inlet connection (240) and

discard the O-ring (241). Tip out the retaining

spring (284), filter (242), adjuster assembly (285),

regulating spring and peg (286) and piston (287).

Invert the end plate and lightly tap it on a flat

surface, taking care not to damage the

aluminium face of the end plate and remove the

regulating sleeve (245), sealing washer (248) and

priming spring (288).

2.6 ELECTRIC SHUT-OFF SOLENOID (ESOS)

Remove any detachable electrical connection

screw(s) or nut (6), washer (7) and connection (5),

depending upon the type of ESOS fitted; slacken and

remove the ESOS body (1). Remove the armature

(or plunger) (4) and spring (3). Remove and discard

the O-ring (2).

If no ESOS is fitted, a solid plug will take its place if

so, remove the plug and discard its O-ring.

Note: On later solenoids, the spring is attached to

the plunger and is retained within the body.

JPT

A1018

A493

A1302

A1008

13

14

1

2

3

5

6

7

8

9

11

12

4

240241

284

285

242

287

288

245

248

286

10

DISMANTLING

2 - 23

A964

A1038

2.7 TRANSFER PUMP

2.7.1 Removing the transfer pump components

Note: Make a note of the orientation of the transfer pumpliner (2) before dismantling, particularly theposition of the recess (4) in one face, to aidcorrect reassembly.

Remove the transfer pump sealing ring (1). Carefullylift out the liner together with the two pairs oftransfer pump blades (3) and their separatingsprings (not visible).

CAUTION: Internal recirculation

If fitted, remove the spring and poppet valve,which are retained within the barrel by the liner.

The springs are very small and could be easilymislaid.

Note: Care must be taken to avoid damage to the blade

rubbing faces during storage or assembly.

2.7.2 Slackening the transfer pump rotor

Temporarily refit a drive hub and key to the shaft andpush the hub fully onto the shaft taper; hold the hubwith the special tool (1). Hold the transfer pumprotor with the special tool (2). Slacken but do notremove the rotor; the direction in which it is to beslackened can be determined by examination of theend face of the rotor.

Rotors marked with an arrow indicate the directionin which to turn the rotor to remove it.

Remove the tools; drive hub and key, leaving therotor just finger-tight.

2.8 ADVANCE DEVICE

DP200 utilises a number of different advancedevices. They fall into two main categories;

a) Single piston design.

Direct actuation of the cam-ring by an advancepiston operated by transfer pressure and controlledby a combination of spring and cambox pressure.

b) Servo piston design.

Indirect actuation of the cam-ring by an advancepiston via a servo valve operated by transferpressure and controlled by a combination of springand cambox pressure.

Each of these two types may be fitted with cold starttiming retard with or without a wax motormechanism.

A965

11

2

3

4

21

DISMANTLING

2 - 24

2.8.1 Single piston design with 2 bolt cold advance (CA)

2.8.1.1 Removing the wax motor

Align the pump to place its axis horizontal with

the advance device uppermost. As the CA device

may be fitted to the auto advance housing with

the wax motor facing in one of two positions,

note the direction in which it is fitted.

Slacken and remove any cable retaining nuts and

washers.

Slacken and remove the wax motor (4); discard

the O-ring (3).

Caution: Do not attempt to remove the

plunger from the body of the wax motor. If the

plunger is partially or fully removed from the

body, operation of the motor will be severely

impaired by the ingress of air into the body of the

motor.

The ball valve seat is a press-fit in the CA

housing. Do not attempt to remove the ball valve

seat, ball, or spring. If there is a problem with the

assembly, it must be replaced.

Slacken and remove the two Allen screws (1) and

(2).

2.8.1.2 Removing the CA assembly

Remove the CA body (1); discard the O-ring (2).

Remove the start-retard spring from the advance

housing, if fitted (not shown).

2.8.1.3 Dismantling of the CA piston assembly

Remove the piston assembly from within the CA

housing (1). Grip the piston (2) lightly in a vice

fitted with soft jaws. With a suitable screwdriver,

slacken and remove the screw (9) and remove the

phase plate (8), stop plug (7), stop tube (6), outer

spring (5), inner spring (4), and shims (3).

Remove the piston from the vice.

Caution: The screw will be under considerable

tension from the springs.

Note: Early pumps may be fitted with pistons

that have small flats to assist with clamping in

the jaws of a vice.

A1485 1 2 3 4

A1486

A1487

1

2

1

2

3

4

5

67

89

DISMANTLING

2 - 25

2.8.2 Servo piston design with 2 bolt Cold Advance

2.8.2.1 Removal of the wax motor







washers.


the O-ring (3).

Caution: Do not attempt to remove the plunger

from the body of the wax motor. If the plunger is

partially or fully removed from the body,

operation of the motor will be severely impaired

by the ingress of air into the body of the motor.

The ball valve seat is a press-fit in the CA

housing. Do not attempt to remove the ball valve

seat, ball, or spring. If there is a problem with the

assembly, it must be replaced.

Slacken and remove the Allen screws (1) and (2).


Remove the CA body (302); discard the O-ring

(308).

2.8.2.3 Removing the advance device

Slacken and remove the pressure end cap (325)and O-ring (324).

An auxiliary spring may be fitted. (337)

Remove the advance housing cap-nut (417);remove and discard the sealing washer (416).

Slacken the head locating fitting (420), or transferpressure damper (if fitted), no more than threeturns. Tap the advance housing (323) with a soft-faced mallet to free it from the gasket (415).Remove the head locating fitting and then theadvance housing, complete with the piston.Discard the gasket (415).

If fitted, carefully remove the spring ring (421)retaining the lock-off ball (422) in the headlocating fitting and remove the ball. Discard thespring ring.

Remove and discard the split nylon ring (418), iffitted, and the O-rings (419) from the headlocating fitting.

The piston sleeve (310) and piston (326) may stillbe retained within the housing (302). Remove thepiston and one of the O-rings (309), then lightlygrip the housing in a vice fitted with soft jaws andwith a suitable flat bladed screwdriver lever outthe sleeve using the O-ring groove. Discard theremaining O-ring (309).

A1485 1 2 3 4

DT167 fig 1

DISMANTLING

2 - 26

2.8.2.4 Dismantling the Servo Valve Assembly

The housing and piston assembly (323) containsa servo valve within the advance piston. Removalof the piston from the housing will enable theservo valve assembly to be dismantled.

This device consists of a number of springs andshim washers that are under compression. Caremust be exercised when dismantling the unit.

Remove the retaining circlip (312), using asuitable pair of circlip pliers.

Clamp the piston in a vice fitted with soft jawswith the spring assembly uppermost. A suitablelarge flat steel washer having an internal holediameter of between 7 and 8 millimetres can beused to compress the springs and shims toenable the retaining e-clip (313) to be removed.

Carefully release the spring pressure and removethe shim (314), plate (315), spring (316), stopplate (317), spacer (318), shim (319) and spring(320). The servo valve retaining circlip (321) andwasher (322) can be removed to release the valvefrom the piston.

Some pumps may have an additional springfitted in the piston bore beneath the servo valve.

2.8.3 Servo piston design with 4 bolt cold advance

2.8.3.1 Removing the wax motor







washers.


the O-ring (306).

Remove the cam (410), spring (409) and spring

seat (408) from within the CA housing (302).

Slacken and remove the four Allen screws (301).


Remove the CA body (302); discard the O-ring

(308) and retard pin (406).


Slacken and remove the spring end cap (413) and

O-ring (324).

An auxiliary spring may be fitted (not shown).

Remove the advance housing cap-nut (417);

remove and discard the sealing washer (416).

Slacken the head locating fitting (420), or transfer

pressure damper (if fitted), no more than three

turns. Tap the advance housing (323) with a soft-

faced mallet to free it from the gasket (415).

Remove the head locating fitting and then the

DT157 fig 1

EVD010

DISMANTLING

2 - 27

advance housing, complete with the piston.

Discard the gasket (415).

If fitted, carefully remove the spring ring (421)

retaining the lock-off ball (422) in the head

locating fitting and remove the ball. Discard the

spring ring.

Remove and discard the split nylon ring (418), if

fitted, and the O-rings (419) from the head

locating fitting.

2.8.3.4 Dismantling the piston and servo valve

Remove the servo valve from within the advance

piston.

Carefully remove the circlip (403), washer (404).

If the servo valve is removed from the advance

piston for future inspection, note the way round

it is fitted into the piston.

2.8.4 Single piston design without cold advance

2.8.4.1 Removing the spring cap

Remove the spring cap advance gauge access

screw (1) and discard the sealing washer (2).

Unscrew the advance piston spring cap (3);

remove and discard O-ring (4). Remove the main

advance springs (6) and (7), and shim(s) (5).

Unscrew the piston plug (12); remove and

discard the O-ring (11).

Remove the spring plate (8), circlip (9), and the

retard spring (10) (if fitted).

Note: The start retard spring (10) and the end

plate regulating sleeve retaining spring have

similar dimensions, but their ratings are

different. As this may cause confusion during

reassembly, the springs must be separately

identified.


Remove the advance housing cap-nut (8);

remove and discard the sealing washer (9).

Slacken the head locating fitting (5), or transfer

pressure damper (if fitted), no more than three

turns. Tap the advance housing (2) with a soft-

faced mallet to free it from the gasket (1).

Remove the head locating fitting and then the

advance housing, complete with the piston (10).

Discard the gasket (1).

If fitted, carefully remove the spring ring (6)

retaining the lock-off ball (7) in the head locating

fitting and remove the ball. Discard the spring

ring.

Remove and discard the split nylon ring (3), if

fitted, and the O-rings (4) from the head locating

fitting.

A1009

A1294

A1250

12

34

5

6

78

9

1112

10

10

9

8

7

6

5

4

3

2

1

DISMANTLING

2 - 28

2.8.4.3 Removing the cam screw

Fit the special adaptor (1) to the cam advance

screw (2). Using a suitable socket and wrench,

slacken the cam screw. The cam ring will almost

certainly become stuck in the pump housing.

If the cam ring has become stuck, remove the

wrench and socket from the adaptor; remove the

adaptor from the cam advance screw and tap the

adaptor sideways with a soft-faced mallet until

the cam has been released. Remove the cam

screw from the cam ring.

2.9 REMOVING THE HEAD LOCKING SCREWSAND RELEASING THE HYDRAULIC HEAD

2.9.1 Head locking screws

Slacken and remove the two head locking screws (1)

and (4); remove and discard the O-rings (2) and (3)

and the filters (not shown) in the inner ends of the

screws.

2.9.2 Removing and dismantling the LLA

a) Lock nut adjuster type

A differential valve for controlling light-load

advance may be fitted in place of one of the head

locking screws.

Slacken the locking nut (8) before removing the

valve body (3) from the pump. Remove the

locking nut and discard the seal (7). Remove the

adjusting screw (6) and spring (5). Tip out the

ball (4). Remove and discard the O-rings (1) and

(2). Remove and discard the filter if fitted.

b) Plug adjuster type

With a suitable pointed implement, prize out the

seal plug (278). Unscrew and remove the valve

body (219) from the pump and remove and

discard the O-rings (217 & 218). If fitted, remove

and discard the filter.

Unscrew and remove the adjuster (222) and

discard the O-ring (277). Tip out the spring (221)

and ball (220).

277 219 218 217

278

222 221 220

A967

A1251

A1011b

DT228 fig 4

1 2

1

2

34

12

34

56

78

DISMANTLING

2 - 29

2.9.3 Removing and dismantling the latch valve

a) Lock nut adjuster type

Slacken, but do not remove, the lock-nut (2);

slacken, but do not remove the sleeve (4).

Slacken the valve body (8) and remove the valve

assembly.

Note: The inner O-ring (10) may remain withinthe pump housing

Remove and discard the O-rings (9) and (10).Discard the washer (11) and filter in the end of thevalve body (if fitted).

Remove the adjuster (1) from the sleeve (4) anddiscard the seal (3). Remove the sleeve from thebody (8) and tip out the spring (6) and valve (7).

b) Cap type

Remove the cap (a) and discard the seal (b).

Remove the sleeve from the body (8) and tip out

the spring (6) and valve (7).

Remove and discard the O-rings (9) and (10).

Discard the washer (11) and filter in the end of the

valve body (if fitted).

2.9.4 Removing the hydraulic head

2.9.4.1 Releasing the hydraulic head

Twist and pull the hydraulic head until the large

O-ring (1) is just exposed.

2.9.4.2 Removing the hydraulic head

Realign the pump with its axis vertical, as shown,

and lift the head out of the pump housing;

carefully hold the plungers within the rotor and

invert the hydraulic head.

Note: The rear scroll plate may adhere to the

face of the hydraulic head, if it does, remove it.

Place a plunger retaining cap (1) over the rotor;

remove and discard the large O-ring (2).

Keep the hydraulic head either in a bath of clean

test oil, ensuring that the exposed part of the

rotor is covered or in a clean plastic bag until it is

required for reassembly.

A1518

DT228 fig 3

A1495

A1496

1 2 3 4 5 6 7 8 9 10 11

1

2

1

11 9 10

6 7 8

a

b

DISMANTLING

2 - 30

2.10 DRIVE SHAFT

Remove the circlip (1) and thrust washer (2).

2.10.1 Dismantling the Zero Backlash Drive assembly

2.10.1.1 Removing the drive shaft

Push the drive shaft (1) carefully up through the

front bearing and remove it from the pump,

holding the rollers and shoes in position as the

shaft is lifted above the cam ring.

2.10.1.2 Removing the rollers and shoes

Remove the rollers and shoes, keeping them in

their matched pairs.

Note1: The roller shoe (1) in the rotor tang drive

slot (2) is longer than the others.

Note2: On some later designs, all 4 shoes are the

same length.

2.10.1.3 Dismantling the drive shaft assembly

Note: If the drive shaft is to be replaced, the

components fitted to the shaft may be transferred

if they are suitable for further service.

2.10.1.4 Removing the catch plate and the support plate

If the roller cage and support blocks are to be

removed, place a suitable tommy bar (5)

through the transverse hole in the drive shaft;

grip the drive shaft lightly in a vice fitted with soft

jaws, using the tommy bar to resist the

slackening torque. Use a Torx screw bit and

adaptor to remove the four catch plate screws (2)

and (4). Remove the catch plate (3) and shoe

plate (1).

A970

A1497

A1498

A1499

1

2

1

1

2

32

1

4

5

DISMANTLING

2 - 31

A1500

A1004

A972

A1290

2.10.1.5 Removing the support blocks

Note: There is no support block in the groove

into which the hydraulic head rotor tang fits.

Invert the drive shaft and grip it very lightly,

across two diametrically opposite roller shoe

gaps, in a vice fitted with soft jaws. Use an

extended Torx screw adaptor to slacken the three

screws (1), (2), and (3). Remove the screws, their

flat washers, and the support blocks.

3

2

1

1

1

2

3

4

5

6

7

8

1 2

3

4

2.10.2 Dismantling the splined drive assembly

2.10.2.1 Removing the pump housing

Remove the pump from the Hydraclamp,

carefully holding it together, and place it on the

bench with the drive shaft uppermost.

Align a gap (1) in the weight cage with the centre

line of the pump so that the gap that will be

diametrically opposite will allow the weight cage

to pass the head of the advance device stud as

the pump housing is withdrawn.

Lift the housing off the drive shaft assembly.

2.10.2.2 Dismantling the drive shaft assembly

Lift the drive shaft (1), governor weight cage (2),

weights (3), and thrust sleeve (4) together from

the spacer (5), scroll plate (6), cam ring (7), and

scroll plate (8).

2.11 DISMANTLING THE HYDRAULIC HEAD CHECK AND CHEEK PLATE DESIGNS

2.11.1 Releasing the drive plate screws

Use the special tool (1) to hold the drive plate (3);

use a bi-hexagon socket to slacken and remove the

drive plate screws (2) and (4). Remove the drive

plate.

DISMANTLING

2 - 32

2.11.2 Dismantling the rotor components

Remove the rollers and shoes (1), (3), (5) and (7).

Remove the dowel pins (2) and (4) fitted to the cheek

plate design and the upper cheek or check plate (6).

2.11.3 Removing the lower check or cheek plate

Retain the plungers in their respective bores with the

specified plastic clips (1), short lengths of nitrile

rubber tube, or small corks.

Unscrew and remove the transfer pump rotor, lift out

the hydraulic head rotor and remove the lower check

or cheek plate (2). Refit the rotor to the hydraulic

head, and then refit the transfer pump rotor finger

tight.

Store the head in a covered container filled with

clean test oil.

Remove the rear scroll plate (4) (still within the

housing), cam ring (3), front scroll plate (2), innerbearing (1), and the governor weight cage assembly

(not shown) complete with the weights, thrust

sleeve and thrust washer.

Note1: Some basic designs of pump will not be fitted

with a bearing or scroll plates.

After removal of the cam ring, remove the circlip

fitted in the pump housing before removal of the

weight cage.

Note2: Some pumps are fitted with reverse thrust split

and return rings.

2.11.4 Reverse thrust weight assembly

Reverse thrust split and return rings.

Some pumps will have a two piece thrust ring, a

retaining ring sandwiched between the thrust sleeve

washer and governor weight cage.

Carefully remove the retaining ring (2) and remove

the two halves of the thrust ring (1) noting the

stepped edge for locating into the weight cage.

A1304

A1254

EVD01

1

3 45

7

A975a6

1

2

1 2

A1501b

12 3 4

DISMANTLING

2 - 33

A977

2

3

1

2.11.5 Lock-shaft timing

If the pump is specified with locked-shaft timing,

the screw (3) will be fitted through a two-diameter

spacer (2); if locked-shaft timing is not specified, a

plain spacer will be fitted. Remove the screw and

discard the O-ring.

2.11.6 Removing the drive shaft seal/s

Remove the pump housing from the Hydraclamp

and place it on the workbench with the drive shaft

seals uppermost.

Using the special seal removal tool, carefully lever

out the seal (1) noting the way round the seal is

fitted into the housing.

If two seals are fitted, remove the circlip spacer and

using the special seal removal tool, carefully lever

out the seal noting the way round the seal is fitted

into the housing.

DISMANTLING

2 - 34

COMPONENT INSPECTION AND RENEWAL

3 - 35

3.1 CLEANINGIf water contamination is suspected, carry out aninitial examination of all internal components beforeattempting any further cleaning. Clean out allpassageways in the head and rotor by flushing outwith clean test oil.

Also inspect for unusual marking, deposits, odour,seal swelling in the housing, in which case degradedRME fuels may be a factor.

3.2 GENERAL

3.2.1 Mated and matched assembliesThe hydraulic head and rotor should be separatedand examined; they should be re-matedimmediately after examination and immersed in acovered bath of clean test oil until required forreassembly into the pump.

Note: If light load advance is specified, the meteringvalve will be matched to the hydraulic head.

The following groups are matched and must be keptassembled in their sets:

Rollers and shoesAdvance housing and pistonCam ring and scroll platesStop solenoid plunger and bodyRegulating sleeve, piston and adjusting screwGovernor cover and torque control piston

If any part of a matched set is considered to be unfitfor further service, the whole set must be replaced.

Note: The pump housing drive shaft bush is not aservice repair item; if the bearing is worn, thehousing must be replaced.

3.2.2 Examination and replacementAll components must be checked for corrosion,wear, or damage. Under service workshopconditions it is not feasible to test individual parts orsub-assemblies to determine their suitability forfurther service. Close examination of the areasvulnerable to damage, and interpretation of theresults of tests prior to dismantling, should indicatethe condition of parts.

(a) CorrosionCheck for signs of corrosion or water ingress (rust orstaining) damage to machined surfaces. Theseinclude the pump housing, drive shaft, hydraulichead bore, metering valve and bore cam ring, scrollplates, cheek plates end plate and auto-advancedevice mounting face.

(b) WearInspect drive shaft splines and associated parts forwear or damage. If excessive end-float or radial playwas detected prior to pump strip-down, examine thedrive shaft thrust washer and housing bearing thrustface, governor backplate and thrust face of driveshaft, and governor drive splines, for wear.

(c) DamageInspect all parts for damage or bending due toabuse, especially external levers and controls.

3.2.3 SealsReplace the advance device gasket and all O-ringseals, including the trapped O-ring in thegovernor cover face. Note that overhaul kit does notinclude drive shaft seals, which are stocked asseparate items.

When fitting new O-rings and oil seals, care must betaken to use protection caps to avoid damage to theseals. O-rings must be dipped in clean test oil priorto being assembled. External seals must be lightlycoated with the specified grease. Where possible,inspect seals for small cuts after assembly.

3.3 DETAILS

3.3.1 Hydraulic head rotorWithdraw the rotor from the hydraulic head.Examine the running surface very closely for signsof erosion, particularly the area around the deliveryport. If significant erosion is evident, the head

Documents

Dp200 Workshop Manual