Toyota Land Cruiser 1988 Repair Manual page 53

EM-22
Squareness
---11--
ENGINE MECHANICAL- Cylinder Head
EM0988
EMOS01
EM0281
EM1536
(d) Hand-lap the valve and valve seat with an abrasive
compound.
(e) After hand-lapping, lean the valve and valve seat.
13. INSPECT VALVE SPRINGS
(a) Using a steel square, measure the squareness of the
valve spring.
Maximum squareness: 1.8 mm (0.071 in.)
If squareness is greater than maximum, replace the valve
spring.
(b) Using calipers, measure the free length of the valve
spring.
Standard free length: 51.5 mm (2.028 in.)
Minimum free Length: 50.0 mm (1.967 in.)
If the length is less than minimum, replace the valve.
(c) Using a spring tester, measure the tension of the
valve spring at the specified installed length.
Standard installed tension:
32.5 kg (71.6 lb, 319 N) at 43.0 mm (1.693 in.)
Minimum installed tension:
27 kg (59.5 lb, 265 N) at 43.0
mm
(1.693 in.)
If the installed tension is less than minimum, replace the
valve spring.
14. INSPECT ROCKER ARM AND SHAFT
(a) Inspect the valve contacting surface of the rocker
arm for wear.