5-101.bk Page 36 Friday, March 17, 2006 11:05 AM VALVE SEAT INSERT COUNTERBORE 2. Check surface finish for smoothness. Check counterbore diameter with an inside diameter micrometer (1). Refer back to specifications listed in Figure 5-45. Refer to Figure 5-45. Valve seat at counterbore depth (3): Exhaust: 0.376–0.372 inch (9.55–9.449 mm) Inlet: 0.364–0.360 inch (9.246–9.144 mm) Inlet valve seat insert counterbore diameter (4): 1.8295–1.8285 inches (46.4693–46.4439 mm) Exhaust valve seat counterbore diameter (5):
1.6885–1.6875 inches (42.8879–42.8625 mm) 1 2 Figure 5-46 — Checking Counterbore Dimensions VALVE SEAT INSERT INSTALLATION 5 4 3 Oversize inlet and exhaust valve seat inserts are available in 0.005, 0.015, 0.031, 0.047 and 0.062 inch sizes if counterbore requires machining. 200302a Figure 5-45 — Valve Seat Insert Counterbore Dimensions 1. If required, machine the inlet and exhaust valve seat insert counterbores using tool HT77136. Refer to Figure 5-47. INSPECTION 2. Position valve seat insert (1) over corresponding counterbore. Install inserts using valve seat insert installation set J 38586 (2). Use driver handle J 8092 (3) to drive valve seat insert into counterbore. Refer to Figure 5-46.
1. With valve seat insert removed from cylinder head (2), clean surfaces thoroughly with wire brush. Page 5-36 200 BENCH PROCEDURES 1. Inside diameter micrometer 2. Cylinder head 1. Exhaust valve guide 2. Inlet valve guide 3. Valve seat at counterbore depth 4. Inlet valve seat insert counterbore diameter 5. Exhaust valve seat counterbore diameter