Table 5-2. Direct Support Troubleshooting - Continued
TEST OR INSPECTION
HIGH PITCHED SQUEAL OR GRINDING SOUND FROM CENTER BEARING AREA
Check center bearing wear.
Replace drive shaft center bearing (see para 5-7).
FAILS TO CRANK
Step 1. Check battery charge and starter. Charge battery or repair or replace starter (para 5-12
Step 2. Check if engine is internally seized. Try to rotate crankshaft by turning crankshaft pulley
clockwise. If engine does not turn, engine is seized.
Remove and repair engine (see para 5-11 and Chapter 6).
CRANKS - WILL NOT START
Step 1. Check fuel pump operation. Disconnect fuel line at inlet side of secondary fuel filter and crank
If no fuel flows from fuel line, replace or repair fuel pump (see para 5-16).
Step 2. Check injectors for free fuel flow. Remove fuel pipe between return manifold connector and
injector. Crank engine to pump fuel through injector. If fuel does not flow freely, tag injector,
replace fuel pipe, and check each injector same way.
Replace or repair tagged injectors (see para 6-43).
Step 3. Check for damaged or broken compression rings. Remove air box covers (see para 6-11).
Inspect three compression rings through ports in cylinder liners.
Replace damaged or broken compression rings (see para 6-33).
HARD TO START/STALLS AT IDLE SPEED/DOES NOT RUN SMOOTHLY
Step 1. Check exhaust valve and exhaust valve bridge clearance (see para 6-20 and 6-24).
Adjust exhaust valve and exhaust valve bridge clearances (see para6-20 and 6-24).