Piston Pin And Piston; Cylinder And Cylinder Head - Yamaha YQ50 Service Manual

ENG
ENGINE ASSEMBLY AND ADJUSTEMENT

PISTON PIN AND PISTON

1. Apply :
• Engine oil
(to crankshaft bearing, connecting rod big end
bearing, small end bearing, piston pin, piston
ring grooves and piston skirt .)
2. Install :
• Small end bearing
• Piston Q
• Piston pin E
• Piston pin clip R
NOTE:
• The arrow W on the piston must point to the
exhaust side.
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• Before installing the piston pin clip, cover the
crankcase with a clean towel or rag so you will
not accidentally drop the pin clip and material
into the crankcase.
CAUTION:
• The ends of the piston pin clip must not
come together at the slot in the piston
groove.
• Always use new piston pin clip.

CYLINDER AND CYLINDER HEAD

1. Install :
• Cylinder gasket (new gasket)
2. Check :
• Piston rings
NOTE:
• Make sure the ring ends Q are properly fitted
around the ring locating pins in the piston grooves.
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• Be sure to check the manufacturer's marks or
numbers stamped on the rings are on the top
side of the rings.
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