Toyota Land Cruiser 1988 Repair Manual page 51

EM-20
ENGINE MECHANICAL- Cylinder Head
Intake
rF=IT
54 mm
(~.13
in.)
i
~
r--
-
Exhaust
F"T
59 mm
(2.32 in.)
EM4394
EM1378 EM1516
EM0254 EM0180
Margin
;hickn~ ~
t
r--
=
Length
t
EM0181
EM2534
NOTE: Different bushings are used for the intake and
exhaust.
(d) Using a sharp 8.0 mm reamer, ream the valve guide
bushing to obtain the specified clearance between
the valve guide bushing and the new valve.
Intake clearance: 0.025 - 0.060 mm
(0.001 0- 0.0024 in.)
Exhaust clearance: 0.035 - 0.070 mm
(0.0014- 0.0028 in.)
11. INSPECT AND GRIND VALVES
(a) Grind the valve only enough to remove pits and
carbon.
(b) Check that the valve are ground to the correct valve
face angle.
Valve face angle: 44.5°
(c) Check the valve head margin thickness.
Standard margin thickness:
Intake 1.5-2.1 mm (0.059- 0.083 in.)
Exhaust 1.7- 2.3 mm (0.067- 0.091 in.)
Minimum margin thickness:
Intake 1.0 mm (0.039 in.)
Exhaust 1.2 mm (0.047 in.)
If the valve head margin thickness is less than minimum,
replace the valve.
(d) Check the valve overall length.
Standard overall length:
Intake 124.8 mm (4.913 in.)
Exhaust 128.0 mm (5.039 in.)
Minimum overall length:
Intake 124.3 mm (4.894 in.)
Exhaust 127.5 mm (5.020 in.)
If the valve overall length is less than minimum, replace
the valve.