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Discussion Starter #1
I picked up a 1986 Polaris 600 cheap, figured i could fix it; it wouldn't start.

So I've been tinkering today, went through and cleaned all the carb jets and passages. It starts now, but it doesn't idle great. I turned in all the idle air screws then started it and it was idling at 4000, so i backed them out slowly and evenly across all 3 carbs.

Now the problems... When it gets to about 2000 rpm idle, the engine will stall. It will idle at 2300-2500, but if i give it gas, it will stall..

Any ideas?
 

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Discussion Starter #5
ill have to check those. Not sure if the carbs are synced. ill have to read up on that..

Thanks
 

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Sconnie
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new plugs? first and easiest thing to check
 

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Discussion Starter #7
yep new plugs. .. And i have more info.... i went out there started it and discovered that its only running on one of 3 cylinders. The one on right side. I have to go check spark to those two cylinders but any initial thoughts on what it could be? i suppose i could be anything.

Thanks guys
 

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Discussion Starter #10
i don't believe so.. how easy is it to foul them? i'll have to buy a couple more tomorrow just to make sure they're ok.
 

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SD Rider
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Is there fuel in the carb bowls? Could be a blocked fuel line that lets enough gas in to let it run at lower rpm's but can't keep up with the demand at higher rpm's and makes it bog.
 

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Discussion Starter #13
Is there fuel in the carb bowls? Could be a blocked fuel line that lets enough gas in to let it run at lower rpm's but can't keep up with the demand at higher rpm's and makes it bog.
yeah when i disassembled them to clean them there was fuel in each bowl.
 

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A lot of issues like this arise when people only put a gallon or so in the tank. I will bet if you put a couple more gallons in, it will be fine.
 

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Discussion Starter #15
Did a compression test.... cylinder that is running reads 90psi. center cylinder reads 65 psi last cylinder closest to the belt reads 110psi..

Rebuild in order?
 

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Did a compression test.... cylinder that is running reads 90psi. center cylinder reads 65 psi last cylinder closest to the belt reads 110psi..

Rebuild in order?
Ouch! Definitely time to check the top end out. Probably rings, and maybe the center jug and piston.

Did you try putting more fuel in anyways?
 

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Discussion Starter #17
Ouch! Definitely time to check the top end out. Probably rings, and maybe the center jug and piston.

Did you try putting more fuel in anyways?
i was going to run down to the gas station but i figured id try the compression test first. I think i'll skip it now that i have these results.

Looking at pistons and rings kits now. i was looking for a reason to completely restore this thing anyway. :)
 

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Sync those carbs, then try and set the idle screws the same again. It should make a difference, and its just going to take a little playing around to get them just right.
 
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