1986 Ski-Doo Factory Shop Manual, Page 161Get this manual
Section 02 ENGINE SUb-section 07 (503 ENGINE TYPE)
CLEANING
Clean all metal components in nonferrous metal
23,27, Upper fan cowl screwsfan housing screws
At assembly, apply light coat of Loctite 242 on threadsIt should be noted that to correctly remove Loctite locked screw, it is first necessary to slightly tap on head screw to break Loctite bondThe screw can then be removedThis will eliminate the possibility of screw breakage
DISASSEMBLYASSEMBLY
13, Fan retaining nut
To remove or install fan pulley retaining nut, lock fan ley with special holder wrench (Use tool PIN 420876 355)At assemblytorque not to 65 N-m 148 Ibhft)
16,'7, Cylinder cowls