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Action for New Fuel Injection System, HPI !

Introduction of Troubleshooting Unit for HPI Engine, 6D170E-3

From D375A-5, 170-series engine have been modified to -3 conform to Tier 2 engine emission regulationof EPA in USA.In the future, 170 Series engines for models to be introduced to the market will be mounted with -3 one afteranother. For injectors, fuel pumps, various sensors, controllers, etc. composing the engine fuel system (socalled HPI), units and parts common to Cummins engines have been used. So, troubleshooting units to beused are partly common to those of Cummins Engine Company.Therefore, we are going to introduce troubleshooting units to be used on 6D170-3 series engines. ** HPI : High pressure injection

1. Newly Set Units

2. Purpose2-1. Determination of Defective Injector with Heat

Gun (Portable infrared thermometer)(Part Number : 795-799-5510)Troubleshooting Method : Wait until the en-gine to cool down before starting the trouble-shooting. Measure temperature of each cylin-der on the front surface of the exhaust mani-fold for 10 minutes right after the enginestarted. When temperature of a cylinderhardly rises, judge the cylinder to be defec-tive. Covers of the exhaust manifold havebeen structured so that their surface tem-peratures can be easily measured. Heat gun

No. Komatsu PartNo.Cummins Part

No. Part Name Application

1 795-799-5510 - Heat gun To be used for troubleshooting of injector.

2 795-799-5550 3376859 Adapter To be used for measuring pressure of fuel pump.

3 795-799-5560 - Oil pressure gauge To be used for measuring pressure at fuel pump inlet.

4 795-799-5520 - Socket (S) To be used for troubleshooting of engine speed sensor.

5 795-799-5530 - Socket (C)To be used for troubleshooting of water temperature sensor, airintake temperature sensor and exhaust gas temperaturesensor.

6 795-799-5540 - Socket (A) To be used for troubleshooting of temperature sensor.

7 795-799-5460 3824774 Cable To be used for troubleshooting of atmospheric pressuresensor, fuel pressure sensor and actuator pressure sensor.

8 795-799-5470 3824775 Cable To be used for troubleshooting of lubricating oil pressuresensor.

9 795-799-5480 3824776 Cable To be used for troubleshooting of timing pressure sensor, airintake pressure sensor and pump pressure sensor.

**

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Note : The heat gun has the Part Number set by Komatsu but is not a special one and is generally availablein the market. So, if you have any heat gun, you need not purchase a new one. If you purchase it, werecommend Part Number MX2 of Raytek Corp. or equivalent.(For Raytek Corp., contact http://www.raytek.com)

2-2. Diagnosis of Pump Acceptability by Measuring Pump Inlet and Outlet PressuresWhen the pump inlet pressure is normal (below 27KPa) and the pump outlet pressure at each enginespeed is not more than the standard value, the pump is considered to be in the normal state. Forthe detail, please refer to the Shop Manual.When the inlet pressure is more than the specified value, the fuel filter is supposed to be loaded orthe piping is supposed to be clogged or loosened or fuel may be leaking from somewhere. When theoutlet pressure is lower, any of the pump body, pressure sensors or the regulator valve is supposedto be defective.

1) Adapter (Part Number : 795-799-5550)The fuel pump is equipped with a quick coupler for measuring pump inlet and outlet pressures. Thiscoupler does not accept our usual couplers in connection, and we have newly set the adapter, whichaccepts our usual quick couplers and enables to measure pump outlet pressure easily with our usualpressure gauges. Since pump inlet pressure becomes negative, the negative pressure gauge to beintroduced in the next paragraph is necessary for measurement.

Temperature characteristic when the 2nd cylinderis abnormal

Temperature characteristic when all cylinders arenormal

Quick coupler for measuring fuel pump inletpressure

Komatsus Quick Coupler

Quick coupler for measuring fuel pump outletpressure

Adapter

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2) Cable This cable is used in the same way as a T-adapter and for measuring output voltage of a sensor. Also,this cable is used for checking disconnection or short-circuit of a sensor.

2) Oil Pressure Gauge for Measuring Negative Pressure (Part Number : 785-799-5560)This gauge is used for measuring inlet pressure of the fuel pump. The measuring range is from 0 to0.11MPa.

2-3. Diagnosis of Electronic Control SystemThe HPI is equipped with various sensors, and we have set simple sockets and cables to be connectedto these sensors for diagnosis. These cables are common to those used by Cummins Corp.

1) SocketThis socket is connected to a sensor to check disconnection or short-circuit of the sensor.

Part Number

Part Number How to useDiagnosis Example of Atmospheric Pressure Sensor

How to useDiagnosis Example of Intake Air Temperature Sensor

795-799-5540

795-799-5520

795-799-5530

795-799-5460 795-799-5480

795-799-5470

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Feb. 2002

Customer Support Division

3) T-adapter for DEUTSCH ConnectorDEUTSCH connectors have been used for connection of engine controller and engine to machine body.The T-adapters for DEUTSCH Connector, which we introduced you in our previous Parts & ServiceOperation Tips, can be used for connection.

Connection of T-adapter to BodyConnection Connector

Body Connection Connector(2) T-adapter for Body Connection Connector 799-601-9270

Connection to controller of D375A-5(1) T-adapter for Controller 799-601-9350

799-601-9290

Parts & Service Operation Tips No. d1 799-601-9350 T-adapter (40 poles) Adapter for controller SEKN50152 799-601-9290 T-adapter (31 poles) Adapter for body connection connector SEKN50053 799-601-9270 T-adapter (21 poles) Adapter for body connection connector SEKN5005