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Discussion Starter #1
This is not my first problem with a Ski Doo. In fact my back yard looks like a used snowmobile dealership with all the sleds and tracks back there. Usually when I have a problem with on of the sleds I come to this site and with all the great resouces I can figure it out but I am frustrated with this one, and almost to the point where I want to pay someone else to just fix it.

My 96 SS 670, starts and idols fine, however is idols real low. All my other Ski Doos tend to idol in the 1800 range this one is closer to 800. The minute I hit the gas it just dies. When I do actually get it to run, it fouls out the right plug within 80 miles. I pulled off the RAVE valves and cleaned them both, thanks to the guide on cleaning them I found on this site, and the one on the cylinder fouling plugs was caked in gas and oil. The plug when I pull it is wet and black and the tip of the plug is brown.

My mechanical skill is so-so and I am certainly willing to try something myself before paying someone to do it for me. But I am not sure what to do, I know the next step will most likely be messing with the carbs but I have never done that before, but willing to try with guidance. Thank you for any help you guys can give me!!

-Adam
 

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I am Spartacus
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Have you ever cleaned the carbs? Sounds like there may be a blockage in the idle circuit. Have you done a compression test?
 

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Discussion Starter #3
New sled to me so no, took off the carbs this morning, they don't seem to dirty inside, but that doesn't mean one of those little jets can't be plugged, I did some research and found that the air screw should be 2.25 turns from closed, and the carb that was connected to bad cylinder was almost 3 turns, where as the other was exactly 2.25. I don't know if that would cause any trouble.

Have not done a compression test but I highly doubt that is it, this thing takes all my strength to get it to turn over. But I will do one later tonight and get back to you what they come out at.

Where is the idle circuit? Not sure which one that is, thanks for all the much needed help!!
 

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Discussion Starter #4
I took the carbs off, cleaned them, the pilot jet had some clog to it on the bad side, I cleaned it with picture wire, put everything back together, i set the slide gap to a little under 2.5mm I had no way to accurately measure any smaller, I realize there may be some time before the thing starts after a carb cleaning but I am on my 20th pull and every now and then I get a quick chug making it sound like it wants to go, but nothing.....
 

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Discussion Starter #5
Bump :)
 

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i usually just dump a little gas in the air box to get em to take off... if it doesnt pick up fuel after a couple shots/trys like that maybe you have a delivery problem from before or possibly just created it... prolly good to rebuild the pump for a wopping $7 and inspect and replace old rotten fuel lines. And deffinetely do the comp. test first...
 

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is the carb gettin gas at this point? can you actually see it in the line? dump some gas in the plug holes of the cylinders ( not in the air box). pull it over a couple times it should start and pull some gas thru
 

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Discussion Starter #8
Ok just did the compression test, 115 in both cylinders, Just for the hell of it I gave it a pull after the test and it almost fired, without a prime or anything... gas is definantly going to it, I can see it in the line. And I got shocked a little by the plug, so spark is good... I am going to try some gas in the cylinder in the morning and see what it does....
 

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Discussion Starter #9
oh and the sled is quite clean, no rotten fuel lines or anything like that
 

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Discussion Starter #10
put some gas in the cylinders, it wants to kiack but just wont go...
 

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Discussion Starter #12
Changed the Plugs to no luck, I took the carbs back off and checked all my settings, it just wants to fire but just wont.... disheartening at this point...
 

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were the float bowls full of fuel when you pulled them back off???... when i tried to start my mxz this year it took forever to get the fuel up to the carbs it was completely empty the pull start broke last year so i had not started it all summer. i did take the plugs out like ten times and give it a little fuel at a time and put the plugs back in blah blah blah to much work i dont care what the other guy says just give it a little in the air box pull it over until it starts and stalls and just keep going until it starts and continues to run on its own
 

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i hav the same sled ( 96 formula ss 670 ) and hav issues with starting it , seems very finiky , if its cold and you prime it it will start and run it will idle no prob goes like snot and if you shut it off it will fire right back up with no problem no primer but if you let it sit for a while so its not at running temp and its not stone cold yet, i can pull this thing 500 times and it does nothing but backfire and flood , seems it runs much too well when it is running to be major and hav only had this sled for a few days so dont know it real well but the thing is in mint condition and just makes no sense , so if you are riding and stop somewhere you must make sure to not be more than a few minutes or be long enough for it to cool right off or you can be stuck there for a long time, can pull the plugs put new ones in doesnt change a thing, let it dry out etc and seems to make no difference ????? any ideas
 

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Discussion Starter #15
I figured out my problem, fuel in the crankcase, all I can say is shut the fuel valve off whenever it sits no matter how short it is sitting
 
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