1999 Ski-Doo Factory Shop Manual Volume Two, Page 169Get this manual
Subsection 09
Section 04 ENGINE (ROTARY VALVE, COOLANT PUMP AND RESERVOIR)
For opening mark, first align 360 line of degree wheel with BOTTOM of MAG side inlet portThen, find 132 line on degree wheel and mark crankcase at this point1 132
To Time Rotary Valve Exactly to Specifications
NOTE: If desynchronization (out of spec is unknown, install rotary valve to determine it before proceeding with the followingFirst Method Turn crankshaft to bring MAG piston to TDCScribed marks of crankshaft and upper crankcase must alignThese marks were scribed to determine desynchronizationInstall brass gear on rotary valve shaft with its marked spline positions (splines) away for one degree of desynchronizationTurn in the opposite direction of desynchronizationFor instance, rotary valve is retarded by 2.5, turn brass gear by 10 splines counterclockwiseSecond Method Turn crankshaft to bring MAG piston to TDCScribed marks of crankshaft and upper crankcase must alignThese marks were scribed while determinating desynchronizationFor each degree of desynchronization, rotary valve shaft should be turned in the opposite direction by about splines on the rotary valve gearNote position of rotary valve gear mark when brass gear disengages worm gear of crankshaft at removal of rotary valve shaftFrom this position, turn shaft accordingly then reinstallFor instance, take valve advanced by 2F01D2JA