SYMPTOM CAUSEHooting Sound. Irregular air control at BOV.

Growling sound and #1 bearing support andpossibly vibration. adapter out of round.

SYMPTOM CAUSE Very high T5. Open bleed valve or late

closure of BOV. Surging Compressor . Bleed Valve closing early.

Rumbling Compressor. Fluttering bleed valve. Hot start, hung start, BOV on wrong side of engine. choking/stall.

SYMPTOM CAUSE Erratic T5 reading. Loose trim stick terminals. High T5 Corroded trim resistor

connection. Low T5 Several burnt thermocouples

or corroded trim probes lead. T5 Difference between Engine with different both engine. temperature profiles.

No reading after repair. Thermocouples lockwired to ground.

SYMPTOM CAUSE High torque reading Stuck T/M control valve

(return spring or sleeve valve) T/M reading levels off but Leakage from the aft sealing actual torque still increasing ring Dropping torque pressure Worn T/M Seal

Fluctuating T/M pressure Fluctuating oil pressure or undersize T/M valve

T5 SYSTEM

TORQUE SYSTEM

1. Trouble Shooting Quick Re

COMPRESSOR

BLEED VALVE

© Dade Sobarna

SYMPTOM CAUSE Oil in compressor Oversized #1 bearing (or at bleed valve) labyrinth seal Oil smell in the cabin Oversized #2 bearing rear

labyrinth seal Smoke at start up and/or Oversized #2 bearing front shutdown. Burnt oil on turbine labyrinth seal Black exhaust smoke during Oversized #3 bearing operation. labyrinth seal. Oil mist in overboard Broken carbon seal breathing. Erratic oil pressure at altitude. Low static pressure in oil tank.

SYMPTOM CAUSE Oil leaking at compressor Check valve stuck open. inlet or #1 bearing.

Fluctuating oil pressure. Clogged or damage oil filter element, broken check valve spring, or scored pressure relief valve.

Increase in oil temperature. Stuck check valve causing bypassing of oil past the relief valve.

Oil leaking out of bleed valve. Static leak from oil tank. Low oil pressure. Blocked oil filter. High fluctuation of oil pressure High tank air pressure at high altitude. differential. Oil smell in the cabin. Excessive oil crossing the

#1 labyrinth seal. Oil smell in the cabin and Excessive oil crossing the oily diffuser pipes. #2 rear labyrinth seal. 24 psi decrease in oil pressure. Oil filter is bypass due to

backwards oil filter. High oil temperature Diverter valve not diverting

oil to oil cooler Oil pressure increase with Ng Cracked main oil pressure speed. pump housing. High oil consumption. Oil leaking from oil-to-fuel

SECONDARY AIR SYSTEM & BR

OIL SYSTEM

heater, mixing with fuel and burning.

FIXSwitch bleed valve or swap to otherside.Replace support and adapter assy.

FIX Clean mettering orifice, change diaphragm, or switch bleed valve. Clean the C-D orifice Switch bleed valve. Switch bleed valve Swap BOV to other side.

FIX Repair terminal block. Clean connection.

Replace trim stick Replace thermocouples Check T5 gauges* by switching from side-to-side, verify trim stick by comparing log book trim value to that on stick. If OK, no further action required. Remove lockwire and correct.

FIX Apply Nitrogen to T/M oil pressure port to engine & rock prop. Shaft Replace T/M sealing ring. Check for potential overtorque. Increase oil pressure (within limits). If pressure continues to drop, replace seal. Replace pressure regulating valve or replace T/M valve

eference

FIX Replace labyrinth seal

Replace labyrinth seal

Replace labyrinth seal

Replace labyrinth seal.

Replace starter-generator carbon seal Check for proper operation of the tank pressurizing valve. Change O-ring on oil filter housing.

FIX Remove the housing and clean. Let sit for 10 minutes. If oil present, repair or replace check valve. If oil not present, check and replace the filter housing O-ring, the center tube O-ring, or the pressure pump drive shaft diaphragm seal.

Check the oil filter element, check valve, and pressure relief valve.

Remove and replace the check valve.

Check O-ring on oil filter housing. Clean or replace oil filter. Change O-ring on oil filter housing. Check tank pressurizing valve. Remove and repair gas gen section.

Remove and repair gas gen section.

Install oil filter correctly.

Check diverter valve operation.

Replace main oil pressure pump.

Replace oil-to-fuel heater.

EATHER

© Dade Sobarna