TM 10-3950-206-12
damaged or stripped threads.
(3) Replace any defective parts found.
d. Reassembly. Reassemble the oil filter in
reverse of disassembly.
e. Installation. Install the oil filter in reverse order
of removal. Tighten cylinder head bolts and re-torque
cylinder head (after engine has reached normal
operating temperature) in accordance with figure 4-9.
4-53. Cylinder Head
a. Removal.
(1) Remove the pollution control valve hose
and tube assembly (para 4-45).
(2) Remove cylinder head per instructions on
b. Cleaning and Inspection.
(1) Remove all carbon from combustion areas
with a scraper and wire brush. Clean all remaining
residue from cylinder head with an approved cleaning
solvent. Dry with compressed air.
(2) Clean top of cylinder block- with a scraper
and a cloth dampened in an approved cleaning solvent.
Be very careful not to get dirt in cylinders or water jacket.
(3) Inspect cylinder head for cracks, corrosion,
damaged threads, plugged water ports, or other defects.
(4) Check flatness lengthwise with a straight
edge and feeler gage (fig. 4-37).
The maximum
Figure 4-34. Oil pressure regulator valve, exploded
permissible low spot is 0.004 inch in , the center,
view.
gradually decreasing towards the ends. Check flatness
lengthwise at each edge and in the middle of the head.
4-52. Engine Oil Filter
(5) Check flatness crosswise with a straight
a. Removal.
edge and a feeler gage (fig. 4-38). The maximum
(1) Remove oil hoses (13 and 18, fig. 4--35).
permissible low spot is 0.003 inch in localized areas.
Remove elbows (10 and 11) and bushing (12).
Check flatness crosswise at each end and between each
(2) Remove two cylinder head bolts and
combustion chamber.
washers that secure filter bracket (20) to cylinder head.
(6) Inspect cylinder head studs for looseness
Remove oil filter assembly.
or damaged threads.
b. Disassembly.
(7) Replace gasket, hoses, and defective
(1) Loosen screw (1) and lift off cover
parts.
assembly. Remove spring (4) from detent in screw (1)
c. Installation.
and remove screw and washer (2) from cover (3).
(1) Install the cylinder head in reverse order of
(2) Remove and discard gasket (5) and
removal.
element (6).
(2) Tighten cylinder head bolts in sequence
(3 If further disassembly is required; re- move
shown in figure 4-39.
four nuts (9), lockwashers (8), flat washers (7), and
(3) Run engine until it reaches normal
bracket (20).
operating temperature and re-torque cylinder head bolts
(4) Remove brackets (15) by loosening screws
to specification.
(17) and sliding off shell assembly (19).
c. Cleaning and Inspection.
4-54. Manifolds
(1) Clean all parts with an approved cleaning
a. Removal,
solvent and dry thoroughly.
(1) Remove carburetor (para 4-42).
(2) Inspect sealing edges of shell and cover for
burrs, or deformation.
Inspect threaded parts for
4-40
