Kolpin Powersports 180??, Service Manual

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FIG-18. Engine Disassembly
CYLINDER HEAD DISASSEMBLY
Remove the valve cotters, spring retainers and valve
springs with a valve spring compressor.
(Photo 32)
INSPECTION
Clean off all carbon deposits from the combustion dome
and check the spark plug hole and valve area for cracks
(Photo 33)
Measure the cylinder head diagonally for warp with a
straight edge and feeler gauge.
(Photo 34)
Measure the free length of the inner and outer valve
springs.
(Photo 35)
SERVICE LIMITS: Inner 31.2 mm
Outer 34.1 mm
Inspect each valve stem for turning, burning, scratches
or abnormal wear.
Check the valve for movement in the guide.
(Photo 36)
Measure and record each valve stem O.D.
SERVICE LIMITS: 4.90 mm
Measure and record the valve guide I.D.
SERVICE LIMITS: IN / EX 5.30 mm
Calculate the stem-to-guide clearance.
SERVICE LIMITS: IN 0.08 mm
EX 0.10 mm
NOTE: If the stem-to-guide clearance exceeds the
service limits, determine if a new guide with standard
dimensions would bring the clearance within tolerance.
If so, replace guides as necessary and ream to fit. If the
valve guide is replaced, the valve seat must be ground.