-follow a service manual for any type of repair
-replace worn parts
-replace gaskets,seals
-check the engine ring end gap, minimun of .012
-tighten hardware to proper torque specs(use lock-tite where needed)
-pressure test the engine before startup
-clean entire carb spotlessly( all jets and pasage-ways)
-follow factory specs for carb jetting
-check ignition timing
-install the correct spark plugs
-use the correct octane rating in the gas(see octane post in FAQ section)
-retorque engine head bolts before starting, warm engine(10-20 min.) and let it cool, and retorque the head bolts again.
-From '73 on, mix the gas at 40:1 for the first tankfull when re-ringing or new pistons were installed, then mix as normal at 50:1
-during break-in, don't run the engine wide open for extended times, you want to vary the throttle.
-check the color of the spark plugs frequently(cardboard color=normal, white=lean,black=rich), running lean will cause severe damage
Tips on rebuilding your snowmobile engine
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Posts in this forum are limited to approved members to keep things clean. If you have a question about a topic here, please post it in the appropriate tech section.
-
- Posts: 2965
- Joined: Thu Jul 14, 2005 12:00 am
- Real Name: Pat Scott
- Location: Southeast Pa.
Tips on rebuilding your snowmobile engine
'76 440 cyclone
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
- guitardude081
- Posts: 989
- Joined: Sun Sep 11, 2005 12:00 am
- Real Name: Jack Durand
- Location: Brainerd, MN
Tips on rebuilding your snowmobile engine
Also...
-On oil injected models make sure to bleed oil pump how it says to in the book
-On liquid cooled motors make sure to check coolant level after it has been run
-Don't forget to connect your impulse line
~Jack
-On oil injected models make sure to bleed oil pump how it says to in the book
-On liquid cooled motors make sure to check coolant level after it has been run
-Don't forget to connect your impulse line
~Jack
Owner, Durand Motorsports
1980 Trailfire 340 (Grandpa bought new)
1983 Trailfire LX
1982 Spitfire (Grandpa bought new)
(3)1974 295/S
1975 340/S
(2) 1978 Liquifire
2003 Ski Doo Renegade 600HO
1993 Polaris XLT Special with AAEN pipes
2020 Polaris Indy 600 XC 129 40th Anniversary Edition
1980 Liquifire (currently in pieces)
1980 Trailfire 340 (Grandpa bought new)
1983 Trailfire LX
1982 Spitfire (Grandpa bought new)
(3)1974 295/S
1975 340/S
(2) 1978 Liquifire
2003 Ski Doo Renegade 600HO
1993 Polaris XLT Special with AAEN pipes
2020 Polaris Indy 600 XC 129 40th Anniversary Edition
1980 Liquifire (currently in pieces)