2004 Skidoo ZX Series Service Manual, Page 116Get this manual
Section 04 ENGINES (2-STROKE) Subsection 01 (377 AND 552 ENGINE TYPES)
A01C02A A02C2NA
1Circlip in groove
1Piston notch 2Circlip break at o'clock
Mount tool in piston making sure that circlip break is facing down
CAUTION: Circlips must not move freely in the groove after installationIf so, replace them552 Engine Use circlip installer (PN 529 035 686) to install new mono-hook circlips no10Insert circlip into support in such way that when installed in piston groove, the tab will face upward