Service Manual

7-4 CAMSHAFT/CRANKSHAFT
Crankcase
Crankcase Cover Removal
•
Set the engine on a clean surface while parts are being removed.
•
Drain the oil (see Lubrication System chapter).
•
Remove:
Exhaust Pipe and Muffler (see Engine Top End chapter)
Control Panel (see Fuel System chapter)
Governor Arm (see Fuel System chapter)
•
When inverting the engine is necessary to remove the crankcase
cover, be sure to remove the air cleaner cover and air filter elements.
Gasoline may drain from the carburetor and soak into the filter
elements if the air cleaner case is not removed.
CAUTION
If the carburetor bowl has gasoline in it, the gasoline may spill
out if the engine is turned upside-down. Use caution when
inverting the engine.
•
Unscrew the mounting bolts [A] and remove the crankcase cover [B]
from the crankcase.
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There are two knock pins on the crankcase mating surface. A wooden
or plastic mallet may be used to gently tap loose the crankcase cover.
Crankcase Cover Installation
•
Chip off the old gasket from the mating surfaces of the crankcase and
cover.
•
Using compressed air, blow out the oil passage in the crankcase
cover.
•
With a high flash-point solvent, clean off the mating surfaces of the
crankcase and cover, and wipe dry.
Clean the crankcase and cover in a well-ventilated area, and
take care that there are no sparks or flame anywhere near the
working area; this includes any appliance with a pilot light. Do
not use gasoline or a low flash-point solvent to clean parts. A
fire or explosion could result.
•
Be sure to replace any oil seal removed with a new one.

Install the oil seal so that the marks [A] face out.

Thoroughly pack high temperature grease [B] into the space between
the seal lip [C] and dust lip [D]. Press in the new oil seal using a press
or suitable tools until it is flush with flange surface [E]. Do not damage
the seal lips.
•
When replacing the oil seal [A] of the governor shaft, note the
following.

Install the oil seal into the crankcase cover [B] after the governor shaft
is inserted in the cover, and so that the marks [C] face out.

The depth is 0
1mm(0 0.04 in.) [D].
•
When installing the governor shaft and plate in the crankcase cover,
see Fuel System chapter.