Figure3-80. Exhaust valve guide installation

TM 10-3930-634-34

(f) Grinding will reduce the thickness of the

valve seat insert and cause the valve to recede into the

cylinder head. If, after several grinding operations the

valve recedes beyond the limits shown in figure 3-81,

replace the valve seat insert.

an old insert is reconditioned, the valve inserts must

(g) After grinding has been completed, dean

be ground.

the valve seat thoroughly with cleaning solvent (Fed

(d) Refer to figure 3-81 forexhaust valve seat

Spec P-D-680) and dry with compressed air. Set a dial

insert grinding specifications.

indicator in position as illustrated in figure 3-82, and

CAUTION

rotate the dial indicator to check the concentricity of

Do not allow the grinding wheel to touch the

each valve seat relative to the valve guide. If the run-

cylinder head when grinding the inserts.

out is excessive, check for a bent valve guide before re-

(e) Apply a 30 grinding wheel to the valve seat

grindng the insert.

insert.