TM 5-3805-280-24-2
Engine System Operation and Tests
Leaks in fuel system
Excessive clearance between oil pump gears and
105
20
Fuel injection nozzles dirty or faulty
cover
Fuel injection pump defective (delivers too much
Clogged oil pump screen
Excessive main and connecting rod bearing
fuel)
Fuel injection pump incorrectly timed
clearance
Improper regulating valve adjustment
Piston cooling orifice missing
Black or Grey Exhaust Smoke
Service Problem
Low Oil Pressure at Slow Idle
Excess fuel
Basic Engine Problem
Engine overloaded
Bypass oil check valve failure
Air cleaner restricted or dirty
Defective muffler (causing back-pressure)
High Oil Pressure
Fuel System Malfunction - See Group 115
Basic Engine Problem
Fuel injection nozzles dirty or faulty
Incorrect engine timing
Clogged oil lines
Improper oil classification
Oil pressure regulating valve bushing loose
White Exhaust Smoke
(wanders)
Improperly operating regulating valve
Basic Engine Problem
Stuck or damaged filter bypass valve
Engine compression too low
Defective thermostat(s) (does not close)
Oil Sludge and Dilution
Fuel System Malfunction - See Group 115
Basic Engine Problem
Defective fuel injection nozzles
Coolant leakage into lubrication system
Fuel injection pump incorrectly timed
Incomplete combustion
Excessive oil consumption
Coolant in Crankcase
Defective injection pump (failed internal O-ring seals)
Basic Engine Problem
Excessive Fuel Consumption
Cylinder head gasket defective
Service Problem
Cylinder head or block cracked
Cylinder liner seals leaking
Engine overloaded
Air cleaner restricted or dirty
Abnormal Engine Noise
Basic Engine Problem
Basic Engine Problem
Compression too low
Fuel System Malfunction - See Group 115
Continued on next page
RG,105,JW7655
1921NOV973/4
13-497
