Bombardier SeaDoo 1990 factory shop manual, Page 35Get this manual
Section 03 ENGINE Sub-section 03 (TOP END11
Or, to accurately determine piston to cylinder wall clearance Measure piston 25 mrn (1 in) below skin end perpendicularly)to piston pin 9' Measure cylinder 16 mrn in) below its top edge0
NOTERing piston groove clearance can be correctly measured only on rectangular ring which is bottom ring
perpendicularly (90' to piston pin axis
Rectangularnlng
Ring End Gap
Position ring just above transfer ports, in relation with top of cylinder NOTEIn order to correctly position ring in cylinder, use piston as pusher Using feeler gauge, check ring end gap If gap exceeds specified tolerance rings should be replaced