My 03 mountain cat 900 carburated wont idle down. When I first start it and when its cold it seems ok but after a ride it will hover around 3000 and fluctuate a bit and wont come down to idle. Anyone have this happen?
Mountain Cat High Idle
- Thread starter juneau84
- Start date
Probably a little lean on the bottom. To verify this, flip your choke on for a second or too and c if the rpms drop. if so you need to richen it up on bottom a bit.
Well to tell you the truth i was changing jets for a while, i was running rich and fouling plugs big time then i seemed to fix it but this idle thing was happening and i figured i was lean. So I put everything back to stock settings and it still seems to be doing it. I couldn't find any cracks in the intake boots but maybe I will have to look further. Anybody else have any ideas?
D
diggerdown
Well-known member
Make sure you are on the idle stop on the carb linkage and not holding idle with the cable. Make sure your carbs are in sync. Air screw 1 1/2 turn out, fuel screw 1 1/2 turn out, 50 pilots were stock, you may have to drop to 45's. the main jet has nothing to do with idle.
I have seen a bad TPS setting cause this also.
I have seen a bad TPS setting cause this also.
I beleive the book says 1 3/4 turns for the air screw. Correct?
D
diggerdown
Well-known member
Early build they said 1 3/4 late build 1 1/2. Also make sure your gaskets are good on the top of the carb. If you changed the needle setting you had them off and it is possible one got cracked.
Spray a bit of starting fluid on the crank seals. If the idle goes up, you have a bad crank seal.
I would try screwing the air circuit screws in 1/4 turn and see if it improves
If I remember right my 01 mc 800 would do the same thing. I'd clean and adjust the power valves and readjust the idle and it would go away for awhile. When I would stop if the idle was high I'd have to blip the throttle once or twice and it would idle down. Sometimes it would work while it wouldn't at other times. Not sure if a stuck open power valve would do this or not or If I just got lucky. Personally I hate playing with jetting and the risks of getting it wrong. I'd ante up for an ATAC system and let fly.
Did you ever figure this out? I have the same problem.
Similar threads
