(2)
Remove the manifolds (para. 106b).
(3)
Remove the cylinder head shrouding (para. 68).
(4)
Remove the flywheel and flywheel shrouding (para. 68).
(5)
Remove the fuel pump and adapter (para. 80b).
(6)
Remove the cylinder heads (para.107b).
(7)
Remove the engine and pump assembly (para. 122).
(8)
Remove the water pump and rear panel assembly (para. 125).
(9)
Remove the timing gear cover and accessory drive assembly (para. 131b).
(10)
Remove the oil pan and oil pump assembly (para. 133b).
(11)
Remove the piston and connecting rod assemblies (para. 134b).
(12)
Remove the nuts (20, fig. 31) and lock-washers (19) securing the cylinder block to the
c. Disassembly.
(1) Remove the capscrews (8, fig. 41) and copper washers (7) securing the valve cover (6) and
gasket (7) to the cylinder block (3) and discard the gaskets.
(2) Remove the valve stem rotor cap (12) and valve seat spring lock (11), valve spring seat (10),
valve spring (9), valve (1), guides (4), and valve seat inserts (2) from the cylinder block(3).
d. Cleaning.
(1) Clean parts in an approved cleaning solvent and dry thoroughly with compressed air.
(2) Clean the cylinder block with a clean cloth dampened with an approved cleaning solvent and dry
thoroughly with a clean, lint-free cloth.
(3) Clean the cylinder head, cover and valves with an approved cleaning solvent and dry thoroughly
with compressed air.
d. Inspection and Repair.
(1) Inspect the valve guides for scoring, pitting, boring, cracks, and other signs of damage or
excessive wear. Check the guide inside diameter for wear or out-of-roundness. Replace a
defective guide as necessary.
(2) Inspect the valves for cracks, pits and excessively thin heads. Examine the stems for scoring,
warpage and excessive wear. Measure the valve stem outside diameter for wear in three places.
Use the measurement near the op of the valve stem where the stem does not touch the guide.
The proper stem-to-guide clearance is 0.003 to0.005 of an inch. Replace all defective valves with
stem-to-guide wear exceeding 0.007 of an inch.
(3) Inspect the valve and seat faces for pits, cracks, warpage, 360 contact, and proper seat angle.
Recondition valve or seat faces as necessary. Replace valves if they are badly cracked, warped
or deeply pitted.
(4) Inspect the valve springs for wear, cracks, breaks, and proper tension. Replace all springs that
are worn, cracked, or broken.(5) Inspect the locks and retainers for cracks, chips, or wear.
Replace defective locks or retainers.(6) Inspect the manifold mounting studs, cylinder head
mounting bolts, or hard ware. Replace defective hardware or studs.
f. Engine Valve and Valve Seat Reconditioning.
(1) Coat the valve face with prussian blue and rotate the valve in the valve face and seat. The entire
circumference of the seat should indicate contact with the valve face.
(2) With a suitable grinder and lapping machine, recondition the valve face and seat to correct high
spots, eccentricity, or remove minor imperfections. The valve seat angle is 45
.
Caution: Never turn the valve a complete turn while lapping, as the abrasive in the
compound may groove the seat.
g. Reassembly.
(1) Install the cylinder block manifold gaskets (13 and 14, fig. 26) on the cylinder block (3, fig. 41).
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