1985 Ski-Doo snowmobile Service Manual, Page 352Get this manual
Section 04 ELECTRICAL SYSTEM Sub-section 03 (SPARK PLUGS)
3Hand screw spark plug into cylinder head and tighten with torque wrench: Bosch"M" plug (18 mm) 37 Nem (27 Ibf.ft) NGK"B" plug (14 mm) 27 N.m (20 Ibf.ft)
Proper wrench
Improper wrench
AOOOOO4011
Use proper wrench to tighten the spark plug