TM 9-2320-289-20
Table 2-3. Mechanical Troubleshooting (Con’t)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
29. EXCESSIVE EXHAUST SMOKE DURING OPERATION
Step 1.
Inspect air cleaner filter and polywrap.
Replace air cleaner filter if required. Clean polywrap if required. (See
paragraph 3-9)
Step 2.
Check for contaminated fuel by draining fuel from fuel filter draincock into suitable
container. Check color of fuel to determine if the correct fuel is in fuel system.
Drain fuel and replace if contaminated or incorrect fuel is in fuel system.
WARNING
Diesel fuel is flammable. When disconnecting fuel lines to test fuel flow,
direct fuel spray away from source of ignition. A fire extinguisher must be
on hand in work area. Failure to follow this warning may result in serious
injury or death to personnel.
Step 3.
Step 4.
Step 5.
Check fuel pump operation. Disconnect input fuel line at the fuel filter. Disconnect
pink lead from fuel injector pump. Use a quart capacity container and crank engine
for 15 seconds. Container should be at least ¼ full or contain ½ pt (0.23 I) of fuel.
Install low pressure gage in fuel line. Crank engine for 15 more seconds. Fuel
pressure should be 5.5-6.5 psi (38-45 kPa). Connect fuel inlet line to fuel filter and
connect pink lead to fuel injector pump.
If fuel flow is insufficient, replace fuel pump. (See paragraph 3-10)
Bleed fuel filter. (See paragraph 3-17)
Check crankcase depression regulator valve (CDRV) and hose for restrictions.
Inspect hose and air intake manifold for evidence of oil.
Clean off all traces of oil and clear restrictions or replace CDRV and hose as
required. (See paragraph 3-5)
30. HEAVY KNOCK WITH ENGINE TORQUE APPLIED
WARNING
Before checking for improper positioning and damage, allow exhaust
system to cool. Failure to follow this warning will result in serious burns.
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