1971-1973 Arctic Cat Snowmobiles Factory Service Manual, Page 97Get this manual
CARBURETION (TILLOTSON) 6Remove the diaphragm cover plate, main diaphragm, and the main diaphragm gasketNOTE: Replace the main diaphragm and diaphragm gasket if damage is evidentRemove the low speed mixture needleGrasp the carburetor and place thumb over the inlet control fulcrum pin, inlet control lever, and tension springRemove screw securing components in placeSlowly release thumb and allow the inlet control lever fulcrum pin, inlet control lever, the tension spring, and the needle to disengage the castingNOTE: Tension spring may "fly out" if care is not exercised when components are removedIf tension spring is distorted or condition is doubtful, replace with new spring