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Discussion Starter #1
i am thinking this might be what is wrong with my 670 it floods at idle i take the carbs off and have the needle and seat out but i am not seeing this 5 notch with a e clip like i have read what exactly am i looking for
 

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The notches and Eclip are found right at the spot that the cable enters the carb cap. Adjusting the Eclip will affect from about 1/2 to 7/8ths throttle with maximum effect at 3/4 throttle. Adjusting the Eclip will have NO effect on idle. Idle speed screws and idle air screws will, as will a number of other things.
 

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Are these round slide or flat slide carbs. I assume round. On round slide carbs the idle air screw is turned clockwise to richen idle mixture. Air screws almost never need to be backed out more than 2 turns. On flatsides the idle fuel screw is turned clockwise to lean mixture. Again almost never more than two turns. On both of them, the idle speed screws turn clockwise to increase speed.

With the idle speeds screws backed of,f the slides should be all the way down in the carb throat. Turn in the speed screws till they touch the throttle slides and then adjust them in the exact same number of turns for each carb. Maybe 2 for starters. I've seen some where one cyl was doing all the work @ idle cause one idle screw wasn't even lifting the slide at all.
 

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Discussion Starter #4
thanks for the replies i have messed with them making the carbs rich and lean still nothing the sled idles fine when you first start it then around 30 seconds later it bogs down and then bogs completely out the carbs are very clean i have cleaned them three times also when i mess with the idle srew it does nothing to the idle it doesnt go up or down
 

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You need to go to the How To Section and no threw the carb. The E clip is atop of the Jet Needle that goes down threw the slide. The needle and seat are on the bottom and adjust the fuel level in the bowl! They need to be set at Level with carb flange, when the flow stops.
 

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The float needles wear out over time causing them to leak slowly. When the sled is left idling the fuel level in the carbs can slowly rise causing the engine to flood.
I have struggled a few times trying to adjust carbs then latter finding this problem.
 

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i bet that's why my '97 Summit is always hard to start when it's warm...
 

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I have a similar issue with my 92 ski formula 468. The carbs will lift up and when the one lifts up some fuel comes out where the jet is. I've cleaned them don't know if they are all cleaned cause my mechanic told me they didn't look dirty
 

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There was a period of time through the mid 90s that the float level on the Ski-doo machines was too high and this made them prone to flooding especially if you stopped with the nose pointed downhill.
 

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OP said the 670, but didn't say which machine it is.

Curious if it has a HAC. If so, the HAC is probably bad and when they go bad, the machine runs extremely rich. Goes through fuel like crazy and will idle rough. Going through the HAC removal process is a good idea.

And Steepndeep is correct, this issue was particularly bad with HAC machines.

I have a 583 that I did the HAC delete on and the gas mileage more than doubled and it ran great for a long time after that. Right now it needs needle/seat replacement, but it's been -20F or colder since before Christmas.
 
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