FIGURE 4-17. Checking Seat Angle.

TM 55-1905-223-24-4

(3) Grind the valve seat to remove scores, scratches and burns.

(4) Check seat angle as shown in FIGURE 4-17. Intake: 30 degrees; Exhaust: 45 degrees.

(5) Install the valves in their respective bores and measure depth again.

(6) Record the depth of each valve as (B) (See FIGURE 4-18). Calculate grinding depth (GD) as follows: CD

= (B) -(A).

CAUTION

Replace the valve if the depth exceeds the limit.

Limit: CD: 0.010 inch (0.254 mm)

FIGURE 4-18. Calculate Grinding Depth (B).

4-18