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94 arctic cat jag 440 fan wont idle

6748 Views 5 Replies 4 Participants Last post by  vetboy
my brotherinlaw has a 94 arctic cat jag 440 fan that wont idle otherwise it runs awsome it only has 150 miles on it now (we went riding saturday) is this typical of a new sled (only had 48 miles on it when he got it) or would a carb rebuild be a good idea. i already tore the carb down and cleaned the hell out of it. it runs really good except for the idle mid range and top end power is good . any suggestions will be appreciated

My wife said its me or my sleds... Im sure gonna miss her
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Bob, regardless of its milage this is an old sled and as such could have old sled trouble like bad crankcase seals, but I would stick to the carbs a little longer.Please don't be insulted but did you really, really , clean the carb or just spray it with carb cleaner. You gotta take the following things apart {mikuni} slide, needle jet,jet needle, main jet, needle & seat, pilot screw, pilot jet and choke. clean each and every orifice and each jet completely use a powerful light and a magnifing glass if possible and spend some time on the orifices that start in the air horn of the carb. They are the ones that effect starting. If all this stuff is good, then you might want to pressure test the engine for leaks.PS. look at the piston skirts from the carb side. I had a sled that was horrible to start but ran fine and it had a broken skirt.Anyway good luck and let me know what you find. Later!

Mean Green Racing
Elyria, Ohio
yes i really tore the carb down and cleaned the hell out of it pulled everything out of it and cleaned it all got it so it wasnt running rich anymore after we got it running then i tried the idle screw till it was all the way in and it still wouldnt idle and sometimes needs to be started with half choke even after being run for awhile ill just rebuild the carb and get it over with


My wife said its me or my sleds... Im sure gonna miss her
id take a better look at the pilot jet cause thats what takes care of the idle to mid range where your having the problem, the air screw on most mikuni is 11/2 turns out from seated + or - 1/4 , so that gives you a baseline, there should be jetting recomendations in the owners manual to help you also.

if its not a CAT, then it must be a dog!
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