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Technical Information & FAQ Articles
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Matt.
Wiring Diagrams:
Problems to Watch out For
Outer crankshaft seals fail (Both
engine brands): It is common place for the crank seals to
go bad on these 25+ year old engines. When they fail, they allow
air into the crank case, which causes the critical air/fuel mixture to
lean out, which means the mixture is heavy on air/weak on fuel.
Because fuel also acts as lubrication on 2-stroke engines, the lack of
lubrication causes excessive heat, which leads to a melted
piston. To avoid this, it is highly reccomended that you replace
the two outer crank seals. This can sometimes be done without
tearing down the entire engine, but while you have the engine out, it
does make sense to replace all gaskets, piston rings, inspect the crank
shaft, etc.
Kawisaki engine
The #1 failure reason for JD snowmobiles is dirty carbs. The
plastic JD used in their tanks seems to leech something into the gas
that produces a substance similar to Tapioca pudding when a machine
sits unused and the gas isn't stabilized. This clogs jets and jams
floats, and the result is a burned piston on the first ride of the new
season. This tends to destroy both the pistons and cylinders, and the
result is a $100 snowmobile that needs an engine rebuild. Every engine
failure I've seen is for this reason - JD Owners KEEP YOUR CARBS CLEAN!
When the rev limiter in 80-84 Liquifires goes bad, it does not
let the engine engage the clutch. A quick fix is to simply
disconnect it. .
The plastic hyfax slides tend to wear rapidly near the front of
the skidframe. If they wear through, the cleats will quickly wear
through the aluminum slide rails causing expensive damage.
The aluminum cross shafts tend to sieze in the suspension arms.
These should be removed and greased every season.
The throttle safety switchs are very fussy about proper
adjustment of the throttle cable. Improperly adjusted cables will cause
an ignition miss and hard starting as the switch intermittently shorts
the ignition.
CCW/Kioritz
Points Ignition: The points surfaces corrode. Clean them with a
file or replace.
The ignition coils tend to go bad, replace them with OEM JD coils for
maximum life. Symptom: The engine runs for 20 minutes or so
before shutting off or running rough. The failure happens when
engine heat is built up in the coils.
The metal gas tanks rust when the gas goes stale inside. Oven
cleaner, along with a lengh of chain, or some loose nuts and bolts
rattled around in the take can help dislodge the debris.
