After a very long break.

summ8rmk

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Are the fuel lines full?

Is the vacuum line from the fuel pump connected to the proper port on the engine?

Does the port provide the proper vacuum?

Is the pickup line and filter clean and clear in the fuel tank and laying on the bottom, covered by fuel?




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Nov 21, 2019
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Yep. All of the lines are brand new, the clunk screen was cleaned and that line replaced, the tank has 3/4 fuel level, all vent lines are on. When fuel is added directly to the cylinder it starts but runs at a very high idle, then dies once the charge is consumed. I think it was burning what I put in, then going lean as it tried to switch to the fuel/air/oil mix from the sled. There is literally nothing else it can be. Compression test shows 115 psi in all cylinders. Carb boots are tight and not cracked, the floats float and pass book test, levels are set. New guts to carbs, all passageways cleaned out. I'll post back here tonight, but that has to be it. Before I 'fixed' it, it would start on the second pull with super old gas.
 

summ8rmk

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High idle is most likely a vacuum leak.
Fill the carbs with fuel, U can do that through the vent tubes.
It should start and run till carbs dry up.


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Nov 21, 2019
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The carbs are full. That's just it. Everything it needs is there. Just put all the coils back in. Did the drill bit method so all carbs are opening simultaneously. Going to adjust throttle lever free play then chokes. Then we'll give it another shot.
 
Nov 21, 2019
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I tore it up! The 2 500s are running like champs. Start on the 1st or 2nd pull when cold. No issues at all. The XLT is the troubled one. All of our snow melted so at least I don't have that hanging over me.
 
Nov 21, 2019
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I do too, because when it runs it sounds freaking awesome. I put a couple of posts out on different forums (Vintage Sleds and Snowmobile Fanatics) about what the deal is and I'm hoping to hear back. It's gotta be something really simple. Put it on here as well in the Polaris forum, 'OLD' sleds lol.
 

Elkaholic4life

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This might be a stupid question but have you cleaned the tank out and dried it. Is it poasable there is water in the bottom of the tank? water will be at the bottom of the tank, maybe the carbs are really filled with water? I had something similar to this happen to me one time
 
Nov 21, 2019
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Yeah, I drained it completely, rinsed it with denatured alcohol, and it sat on my dining room table for a week while I waited for the new seat cover (yep, I live alone0. It had a bunch of water in it when I got it.
 

summ8rmk

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Put ur hand over each carb while someone pulls the rope. Feel for vacuum.
It should suck ur hand in and pull fuel out of the carb bowl and saturate both ur hand and the cylinder.

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Nov 21, 2019
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Some of the early Polaris sleds had reeds, but all of the early to mid 90s sleds that I know of were piston ported. Speaking of the liquid cooleds. To the best of my knowledge anyway.
 
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