TM 5-3805-280-24-2
Engine System Operation and Tests
105
Dirty or faulty fuel injection nozzles
Worn main or connecting rod bearings
21
Incorrect fuel injection pump timing
Excessive crankshaft end play
Fuel injection nozzle tip holes enlarged
Loose main bearing caps
Fuel injection nozzle tips broken
Foreign material in combustion chamber
Carbon build-up in compression chamber
Worn connecting rod bushings and piston pins
Scored pistons
Water Pump Leaking
Worn timing gears
Excessive valve clearance
Seal ring or pump shaft worn
Worn cam followers
Bent push rods
Coolant Temperature Below Normal
Worn camshaft
Worn rocker arm shaft
Defective thermostat(s)
Insufficient engine lubrication
Worn turbocharger bearings
Coolant temperature gauge defective
Fuel System Malfunction - See Group 115
Engine Vibrating
Fuel injection pump incorrectly timed
Fan blades bent or broken
Detonation or Pre-Ignition
Water pump shaft worn
Basic Engine Problem
Balancer shaft/gear broke (4-cylinder)
Oil picked up by intake air stream (intake manifold)
Fuel System Malfunction - See Group 115
RG,105,JW7655 1921NOV974/4
TEST ENGINE COMPRESSION PRESSURE
IMPORTANT: Compression pressures are affected by
the cranking speed of the engine.
Before beginning test, insure that
batteries are fully charged and injection
nozzle area is thoroughly cleaned.
1. Start engine and run at rated speed until it warms up
to normal operating temperature. (From a cold start,
operate engine 10--15 minutes at slow idle.)
Shut off fuel supply and remove fuel injection nozzles.
(See Group 35.)
Continued on next page
RG,105,JW7652 1921NOV971/3
13-498