0B-8 Maintenance and Tune-Up:
Tappet Clearance Inspection and Adjustment
ZAJ6110206006
Inspect tappet clearance
Every 200 hours (12 months)
Inspection
The tappet clearance specification is different for intake
and exhaust valves.
Too small a tappet clearance may reduce engine power,
too large a tappet clearance increases valve noise and
hastens valve and seat wear.
When the tappets are set to the specified clearance, the
engine will run without excessive noise from the valve
mechanism and will deliver full power. In this engine, the
tappet clearance is increased or decreased by replacing
the shim disc, made of a special wear resistant material,
fitted to the top of the tappet. Using the proper tools
provides for easy removal and installation of the shim
disc.
Tappet clearance adjustment should be checked and
adjusted:
• During scheduled periodic inspection.
• When valve mechanism is serviced.
• When camshafts are disturbed by removing them for
inspection.
1) Remove following parts:
• Engine lower side cover.
Refer to “Lower Side Cover Removal and
Installation” in Section 2A (Page 2A-3).
• Ring gear cover.
Refer to “Ring Gear Cover Removal and
Installation” in Section 1D (Page 1D-2).
• Ignition coils and spark plugs.
Refer to “Spark Plug Removal and Installation”
(Page 0B-6) and “Spark Plug Inspection and
Cleaning” (Page 0B-7).
2) Remove the cylinder head cover (1).
Refer to “Cylinder Head Cover Removal and
Installation” in Section 1D (Page 1D-2).
CAUTION
Rotate crankshaft clockwise to prevent water
pump impeller damage.
3) Rotate crankshaft clockwise to bring cam nose
vertical to shim surface.
4) Measure tappet clearances by inserting thickness
gauge between cam and shim surface.
NOTE
• Rotate crankshaft and measure clearance
for each tappet respectively by bringing
cam nose vertical to shim surface.
• All tappet clearances can be measured
during two crankshaft rotations.
Special tool
(A): 09900–20803 (Thickness gauge)
Tappet clearance (cold engine condition)
IN.: 0.18 – 0.22 mm (0.007 – 0.009 in.)
EX.: 0.28 – 0.32 mm (0.011 – 0.013 in.)
5) If out of specification, adjust tappet clearance by
changing shim.
1
IAJ611020021-01
“a”: 90°
(A)
“a”
I9J011020008-01
Summary of Contents for GF60A
Page 1: ...9 9 5 0 0 8 8 L 0 0 0 1 E ...
Page 8: ...00 3 Precautions ...
Page 48: ...0B 22 Maintenance and Tune Up ...
Page 236: ...1K 9 Charging System ...
Page 292: ...2B 27 Power Trim and Tilt ...
Page 336: ...K10 ...