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Mechanical Diagnosis
161
Oil pressure low
Insufficient oil in pan
Add oil
Faulty oil pressure switch
Check oil pressure switch. Replace
if necessary
Oil control valve defective
Check oil pressure control valve
Worn oil pump, camshaft, main or
connecting rod bearings, loose oil
gallery plug
Repair engine
High oil consumption
10 hour engine break in running was
not successfully completed
Run unit for 10 hours in continuous
run as described in the “Unit Check
List” section at the end of the
Precedent Installation Manual TK
55496
Oil leakage
Check and eliminate possible
causes at rocker arm cover, oil lines,
oil filter, front timing cover or
crankshaft seals
Damaged valve seals
Replace seals on valve stem
Worn valve stem
Replace valves
Broken piston rings or cylinder bore
worn or scored
Have engine repaired and rebored.
Replace broken piston rings
Clogged air cleaner system
Unclog air cleaner
Condition
Possible Cause
Remedy
Engine Emits Excessive Smoke
White Smoke
Black Smoke
Blue Smoke
Fuel is not burning
Excessive Fuel to Air Ratio
Oil Consumption
• Air or water in fuel
• Type of fuel used
• Poor compression
• Incorrect timing
• Cold engine
• Defective valve seals
• Poor compression
• Excessive load
• Faulty injectors
• Clogged air intake system
• Improperly installed injectors
• Faulty nozzles
• Poor compression
• Restricted exhaust