Intake and Exhaust Valves - TM-5-4320-234-340071

TM 5-4320-234-34

b. Cleaning and Inspection.

(3) Inspect the cylinder head for cracks,

corrosion, damaged threads, plugged water ports, or

WARNING

other defects.

Clean all parts in a well-ventilated

(4) Check flatness lengthwise with a

area. Avoid inhalation of solvent

straightedge and feeler gage.

The maximum

fumes and prolonged exposure of

permissible low spot is 0.012 inch (0.0300 cm) in the

skin to cleaning solvent. Wash

center, gradually decreasing toward the ends. Check

exposed skin thoroughly.

Dry

flatness lengthwise at each edge and in the middle of

cleaning solvent (Fed. Spec. P-D-

the head.

680) used to clean parts is

(5) Check flatness crosswise with a

potentially

dangerous

straightedge and a feeler gage.

The maximum

personnel and property. Do not

permissible low spot is 0.003 inch (0.0075 cm) in

use near open flame or excessive

localized areas. Check flatness crosswise at each end

heat. Flash point of solvent is 100

and between each combustion chamber.

F. to 138 F. (38 C. to 59 C. ).

(6) Inspect cylinder head studs for looseness

or damaged threads.

(1) Remove all carbon from combustion

(7) Replace the gasket, hoses, and defective

areas with a scraper and wire brush.

Clean all

parts.

remaining residue from the cylinder head with cleaning

c. Installation. Using a new head gasket, install head in

solvent (Fed. Spec. P-D-680). Dry with clean, dry,

reverse order of removal. Tighten the cylinder head

compressed air.

screws according to the sequence shown in figure 4-2.

(2) Clean the top of the cylinder block with a

Torque to 35 to 40 foot-pounds (4.840 to 5.532 kgm).

scraper and a cloth dampened in cleaning solvent. Be

careful that you do not get dirt in the cylinders or water

jacket.

Figure 4-2. Cylinder head capscrew tightening sequence.

(2) Remove the valve chamber cover (7, fig.

4-4. Intake and Exhaust Valves

4-21).

a. General. The intake and exhaust valves

(3) Using a spring lifter, compress the valve

of this L-head engine are mounted in the cylinder block.

spring (5 or 10, fig. 4-3) at each valve (2 or 7) and

They are opened by operation of the camshaft through

remove the valve lock (1 or 6) from each valve that is in

adjustable valve tappets. They are closed by the valve

the closed position. Rotate the engine crankshaft to

springs. The valve stems ride in valve guides which are

close the remaining valves and remove the remaining

pressed into the block. The intake valves seat directly

locks.

in the block. The exhaust valves seat in shrink-fit valve

seat inserts in the block.

b. Removal.

(1) Remove the cylinder head (para 4-3).

4-5