1986 Ski-Doo Factory Shop Manual, Page 45Get this manual
Section 02 ENGINE Sub-section 02 (253 ENGINE TYPE)
I Headcylmder 2Spring bracker 3, Lock washer mm 4, Screw M6)( 12 5_ Injection fitting 6Head cylinder gasket Stud MB 158,5 (41 8_ Lock washer 8.4 rnm (4J
9 Nut M8 (41
iO Clfcltp (2J
7 7_ Sem,trapez ring 72 Recrangu{1r ring 13Piston
14 Gudgeon pin
15, Needle bean-n9
Use engine mounting support (PIN 420876640) to hOld
engine while working on it
CAUTION: When tapping out gudgeon pins, hold ,piston firmly in place to eliminate the possibilities of transmitting shock and pressure to the connecting rod
INSPECTION
The inspection of the engine top end must include the following measurements:
TOLERANCES MEASUREMENTS FITTING NEW PARTS IMIN (MAX.I
.03 mm LOO12") .07 mm0028")
WEAR LIMIT
Cylinder taper
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