1970-1979 Ski-Doo Snowmobiles Service Manual, Page 13Get this manual
CHAPTER ONE
eliminates damaged screw slotsGood ones run about $12 at larger hardware stores3Hydrometer (Figure 5)This instrument measures state of charge of the battery, and tells much about battery conditionSuch an instrument is available at any auto parts store and through most larger mail order outletsSatisfactory ones cost as little as $3