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Discussion Starter · #1 ·
Here's the story. It starts and idles find. The clutch kicks in at about 4000 rpm and it runs fine for awhile while warming up. After it's gotten warmed up, it will hit about 55-6000 rpm and bog down bad. Let off the gas and it will declutch fine and go back to a good idle. Rev it back up and it does not have the power to take off.

Shut it down and let it sit for 5 or 10 minutes, and it starts right up and runs fine till you hit about 5-5500 rpm and it acts like it did before.

The carburetors are completely rebuild, rebuilt fuel pump, new impulse line. I tried a different CDI, and it didn't cure it. I think it's either a short in the stator or a bad ignition coil.

It's a 1991 model.
 

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i had to replace the coil in mine its a 92 had simular symptems, that made a new sled out of it and i just got the $20 one from shadetree, try that
 

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Discussion Starter · #3 ·
Ordered one to try. Should be here tomorrow. I'll let you know if it does the trick.
 

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Discussion Starter · #4 ·
Well the coil didn't fix it. It runs fine to 5-5500, but it's smoking pretty bad. I tried running it off an auxilliary tank today, bypassing the fuel pump. I was told that this will tell you if the crankcase is leaking and messing up the impulse to the fuel pump. It ran exactly the same. I also replaced the fuel line to the tank; the hose and weighted screen inside were fine.
 

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Discussion Starter · #6 ·
Tank vent is fine. I took the tank off, blew through the vent and the hose. I also cleaned the tank out.
 

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how about the main jets? are they cloged?, the chokes work freely? try testing the resistance throught the charge and trigger coils behind the flywheel too, charge is supposed to be around 160 ohms for that sled i know
 

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Discussion Starter · #8 ·
Do I need to pull the recoil start off or can the resistance be checked in the plugin?
 

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you can check it at the 4 wire plug coming out of the engine, i'm not sure which two to check, i think black and black/white, call a dealer or if u have a manual
 

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Discussion Starter · #10 ·
Well, it turns out it's the safety switches on the carbs that's causing the problems. I was working on it awhile ago and I simply touched one of the cables on the clutch side carb and it almost died. I gripped it between 2 fingers and it died immediately. I unplugged both carbs, and the engine would run fine above 3000 rpm's, but when the throttle is released, it will backfire and then die. Is there some way to bypass these switches at the carbs?
 

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i cut the wires on the carb side of the connector
- leave the plug intact
-strip the 4 wires
-connect the 2 wires of each plug together- 2x2
this closes the circuit. that will eliminate any problem, but you wont have any safety if ur cables break
 

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Discussion Starter · #12 ·
One carb was in open position, so I put a shorted plugin in line instead of plugging it into the harness. Sled runs great now. Thanks. Now if we only had some snow; maybe a trip to Rockies is called for next month.
 
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