5-13. CYLINDER HEAD ASSEMBLY REPAIR (CONT).
(1) Clean injector nozzle seats with nylon tube
Compressed air used for cleaning purposes
must not exceed 30 psi (207 kPa). Use
only with effective chip guarding and
personal protective equipment
(goggles/shield, gloves, etc).
(2) Wash cylinder head in hot water and soap
for 30 minutes. Rinse and use compressed
air to dry.
(3) Check cylinder head for nicks, erosion,
cracks, and other damage.
(4) Polish gasket surface of cylinder head
using 400 grit waterproof silicon carbide
(5) Check cylinder head deck for distortion as indicated. Distortion can be no greater than 0.0039 in. (0.010
mm) within a 2 in. (50.8 mm) radius (distance A) or no greater than 0.003 in. (0.075 mm) end to end.
(6) Check valve guides in cylinder head for
scuffing or scoring. Ream valve guides to
remove any surface damage.
(7) Measure valve guide bores at positions B
and C. Normal measurement is 0.3157 to
0.3185 in. (8.019 - 8.089 mm). If less than
normal, rebore valve guide. If greater than
normal, replace cylinder head.
(8) Clean valve heads with a soft wire wheel.
(9) Clean and polish valve stem with crocus
cloth. Remark valves according to head
When replacing old valves, remember to
mark new valves the same for correct
(10) Check for abnormal wear on valve heads and stems. Replace valves that are bent or cannot be ground.