Toyota 4-Runner 1985 Repair Manual page 51

EM-22
Squareness Limit
ENGINE MECHANICAL - Cylinder Head
• Check that the seat contact is on the middle of the
valve face with the following width:
1.2 - 1.6
mm
(0.047 - 0.063
in.)
If not, correct the valve seat as follows:
If seating is too high on the valve face, use 30°
and 45
°
cutters to correct the seat.
If seating is too Iowan the valve face, use 60°
(IN) or 65° (EX) and 45° cutters to correct the
seat.
(d) Hand-lap the valve and valve seat together with
abrasive compound.
(e) Clean the valve and valve seat after hand-lapping.
13. INSPECT VALVE SPRINGS
(a) Using a steel square, check the squareness of the
valve springs. If a spring is out of square more than
the maximum allowable, replace the spring.
Maximum allowable: 1.6 mm (0.063 in.)
(b) Measure the free height of all springs. Replace any
spring that is not correct.
Free height: 48.5 mm (1.909 in.)
(c) Using a spring tester, check the tension of each spring
at the specified installed height.
If the installed tension is less than the minimum, replace
the spring.
Installed height: 40.5 mm (1.594 in.)
Minimum installed tension: 28.5 kg (62.8 Ib, 279 N)