Service manual

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Service Manual
Moby XL, SE-803
Engine Repair Cont.
Crankcase / Engine cont.
With the engine taken down to this level, it is generally accepted that the piston
rings should be replaced. They provide the engine with the proper amount of
compression, and due to their inaccessibility, it’s best to re-assemble with new
rings. However, if servicing requires the removal of the piston, fitting of new
rings to the piston should not be done until the piston has been re-assembled
to the connecting rod, as the piston pin remover tool can cause damage to the
rings.
Using a piston pin remover, loop the strap end around the piston with the hole
aligned to allow the passage of the piston pin. It may be necessary to insert a
small screw between the remover and the piston pin, as the remover may have
a smaller diameter than the inside of the piston pin.
The crankcase halves are joined with four screws. Removing these
screws will allow the entire contents of the crankcase to be exposed.
Inspect the main support bearings, if they are in question replace them.
Upon re-assembly, install a new crankcase gasket between the halves.
Carefully inspect the crankshaft, paying particular attention to the
amount of play between the connecting rod and the crankshaft pin.
Side-to-side play (A) is normal. However, any detectable play in an up-
and-down motion (B) is unacceptable. This indicates the need for a
replacement crankshaft. The connecting rod and crankshaft are one,
non-serviceable part.