TM 5-3805-281-24-2
Cylinder Head and Valves
PRELIMINARY CYLINDER HEAD AND VALVE CHECKS
Misaligned valves.
Make preliminary inspection of cylinder head and valve
Distorted cylinder head.
assembly during disassembly.
Carbon deposits on seats due to incomplete
Look for the following conditions:
Valve spring tension too weak.
Excessive heat.
STICKING VALVES:
Improper valve clearance.
Improper valve timing.
Carbon deposits on valve stem.
Incorrect valve or seat installed.
Worn valve guides.
Scored valve stems.
BURNED, PITTED, WORN, OR BROKEN VALVES:
Warped valve stems.
Misaligned or broken valve springs.
Worn or distorted valve seats.
Worn or distorted valve seats.
Loose valve seats.
Insufficient lubrication.
Worn valve guides.
Insufficient cooling.
WARPED, WORN, OR DISTORTED VALVE GUIDES:
Cocked or broken valve springs.
Improper engine operation.
Lack of lubrication.
Improper valve train timing.
Cylinder head distortion.
Faulty valve rotators.
Excessive heat.
Warped or distorted valve stems.
Unevenly tightened cylinder head cap screws.
"Stretched" valves due to excessive spring tension.
Warped cylinder head.
DISTORTED CYLINDER HEAD AND GASKET
Bent push rods.
LEAKAGE:
Carbon build-up on valve seats.
Rocker arm failure.
Loss of cylinder head cap screw torque.
Incorrect valve or seat installed.
Broken cylinder head cap screw.
Incorrect piston-to-valve clearance.
Overheating from low coolant level operation.
Insufficient liner standout.
IMPROPER VALVE CLEARANCE:
Coolant leakage into cylinder causing hydraulic
failure of gasket.
Inefficient use of fuel.
Leaking aftercooler.
Engine starts harder.
Cracked cylinder head.
Maximum engine power will not be achieved.
Cracked cylinder liner.
Shorter service life of valve train.
Damaged or incorrect gasket.
Greater chance for engine to overheat.
Overpowering or overfueling.
Damaged cylinder head or block surfaces.
EXCESSIVE VALVE RECESSION:
Improper surface finish on cylinder head.
Improperly tightened cylinder head cap screws.
Worn valve guides.
Faulty gasket installation (misaligned)
Bent valves.
Debris passed through valve train.
WORN OR BROKEN VALVE SEATS:
RG,RG34710,1078
1923OCT971/1
