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My edge 600 pops and backfires at idle. Sled seems to have no power. I drained the gas and put new gas in. Cleaned the carbs .everything looked good. Pilots were clean. Put in new plugs and ran it . Pulled plugs and the pto side plug is black and mag side is fine. Checked and cleaned exhaust valves. Stock exhaust and slp can. The top end was rebuilt not long ago and compressionthe is reading 115lbs on each side. There was an old post on here with the same problem but the post never said what the fix was. Please help!
 

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Does it do it when the sled is at operating temp to?
 

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A good crank shop. You can't do it at home. Just a suggestion on the crank. My brother in law's sled is doing the same thing and he found the crank is whacked.
 

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Check your carb/intake boots for leaks. It there is even a slight leak they will make that cylinder pop and backfire, if its bad enough it won't even run.
 

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I chased a backfire pretty much all season last year. First I thought it was the crank out of phase. Had the crank shop check it and it was fine. Then I chased every imaginable electrical problem. Everything was fine. Then I went hard after fuel problems. My fuel system was so clean that I couldn't possibly have a problem there. My problem turned out to be the tiny brass taper on the end of the fuel screw was broken off and stuck in the carb body. My backfire was out the exhaust though. My experience may not relate to you since your backfire is through the carb. You may want to have your crank checked for phase. Where are you? My crankshop checked it out for $30. I'll give you some advice though. Eliminate all simple things before you tear your motor completely down. I wasted endless hours chasing a problem that turned out to be carburetion.
 

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Discussion Starter #10
Rubi said:
I chased a backfire pretty much all season last year. First I thought it was the crank out of phase. Had the crank shop check it and it was fine. Then I chased every imaginable electrical problem. Everything was fine. Then I went hard after fuel problems. My fuel system was so clean that I couldn't possibly have a problem there. My problem turned out to be the tiny brass taper on the end of the fuel screw was broken off and stuck in the carb body. My backfire was out the exhaust though. My experience may not relate to you since your backfire is through the carb. You may want t
o have your crank checked for phase. Where are you? My crankshop checked it out for $30. I'll give you some advice though. Eliminate all simple things before you tear your motor completely down. I wasted endless hours chasing a problem that turned out to be carburetion.
I have checked the boots and they are in great shape. I am going to go thru the carbs again tonight. I' ll let you know what I find. It really seems like a fuel problem to me. I just don't understand why the plug on the side that is backfiring is black.
 

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hydro said:
cooter92 said:
Could a bad cdi make my sled act this way?
Did you check the reeds yet this is a common issue with this model and has the symptoms you are describing.
Agree. Backfiring can take a Petal out.
 

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xcr440 said:
hydro said:
cooter92 said:
Could a bad cdi make my sled act this way?
Did you check the reeds yet this is a common issue with this model and has the symptoms you are describing.
Agree. Backfiring can take a Petal out.
This just happened on my 98 xc 600. The problem was that I had the tempa flow hoses hooked up wrong so it was running out of the mag side cylinder but not the pto. SO i hooked that up right and it took care of the problem now its running like a champ. I would recommend taking a look at the carbs and switching them around to see it that might be the problem. Zach
 

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[/quote]
This just happened on my 98 xc 600. The problem was that I had the tempa flow hoses hooked up wrong so it was running out of the mag side cylinder but not the pto. SO i hooked that up right and it took care of the problem now its running like a champ. I would recommend taking a look at the carbs and switching them around to see it that might be the problem. Zach
[/quote]

what are Tempa flow hoses??? Is this something you named
 

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Discussion Starter #16
Could a bad cdi make my sled act this way?

I have checked the reeds even switched them from side to side. I replaced the cdi but no change. I have tested the tps, ign switch, stator, pick up coil....I'm stumped. Please help! I need to ride!

Ps. I don't know what temps flow hoses are. I can't switch the carbs around if that is what your suggesting. It is a rack system.
 

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Above they were referring to a tempaflow. It is a carb compensator.
 

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I have the same sled and was having this problem all last year, the local mechanic said it was common to have a bad seal and sure enough it turned out to be base gaskets. I would check the crank seals and base/head gaskets.
 

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I have sprayed both the pto and mag crank seals while running which produced no change. I am to the point where i may have to tear it down. Somebody has put piston and rings in this thing but i don't know how good of a mechanic he was or the extent of what he did. It really seems to be an electical issue but you know how deceiving that can be. I do not have a tempa flow system on this sled.
 

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I have sprayed both the pto and mag crank seals while running which produced no change. I am to the point where i may have to tear it down. Somebody has put piston and rings in this thing but i don't know how good of a mechanic he was or the extent of what he did. It really seems to be an electical issue but you know how deceiving that can be.

If the fuel pump is restricted could it create this problem? wouldn't it be backfiring out of both carbs? I feel like i'm chasing my tail on this.
 
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