Immerse cylinder head in a tank of water
heated to 180o-200oF (82o-93oC) for
twenty minutes to heat head. Observe
water in tank for bubbles which indicate a
leak or crack. Check for leaks at top and
bottom of injector tubes, oil gallery,
exhaust ports, fuel galleries, and at top
and bottom of cylinder head.
Relieve air pressure and remove cylinder
head from water tank. Remove regulated
air supply, end plate, injectors, and
blocking plates from cylinder head.
If warpage exceeds limits, reface cylinder
head. Do not remove more metal from fire
deck than minimum distance of 3.536
inches from top of deck to bottom of fire
(1) Cylinder head
Check fire deck surface of cylinder
head for flatness. Using a straight
edge (66) and a set of feeler gages
(67), check lengthwise (six places)
and crosswise (five places) warpage.
Maximum lengthwise warpage is
0.008 inch and maximum crosswise
warpage is 0.004 inch.
Inspect cam follower bores in
cylinder head for scoring and wear.
Clean light score marks with crocus
cloth wet with fuel oil. Measure
diameter of cam follower body and
cam follower bore to determine
clearance. Maximum clearance is
0.006 inch. Replace cylinder head if
bores are excessively worn or
(2) Water nozzles
Check water hole nozzles (68 and 69) for
looseness. If necessary, replace nozzles
(a) Remove old nozzle (68 or 69) and
clean bore in cylinder head.