1997 Ski-Doo Factory Shop Manual Volume Three, Page 172Get this manual
Sub-Section 02
Section 06 REAR SUSPENSION (SC-10 SUSPENSION (HP VERSION))
If suspecting an internal gas leak between oil chamber and gas chamber, check shock as follows: Install shock in vise clamping on its bottom eyelet with its rod upwardLet it stand for minutesCompletely push down the shock rod then releaseRod must comes out at steady speedIf speed suddenly increases particularly at end of extension, replace shockIf suspecting frozen gas shock proceed as follows: Place shock in freezer (temperature below 0C (32F)) for hoursPush down on rod and note its resistance, compare to new shockIf shock is frozen it will be much more difficult to compress than for the new one