89 polaris indy trail 440, smokes and fouls plugs.?

Question

it has two mukuni carbs and its running rich. How do I adjust it so its not running rich anymore? what does rich and lean mean? i was told it was rich but drew a blank....help?

Answer 1

Turn the air/fuel mixture screws in, clockwise. Rich is more gas/oil, lean is more air.

Answer 2

Running rich means it is getting too much gas. Running lean means it is not getting a lot of gas. You want your car to run as lean as possible, which means less gas going through at idle.



If you were running quite a rich mixturek, your plugs would be black with soot. However, you say it "fouls plugs". That sounds as if they may be fouling due to oil.



Anyway, you need to get those carbs adjusted correctly. I imagine you have direct linkage on the carbs. The best tool you can have for adjusting a carburator is a Vacuum Guage. They don't cost much. Just plug it into a major vacuum line and adjust the carbs one at a time, turning the mixture screws until you obtain the highest vacuum reading. I would take one of the carbs "off line" while I was adjusting the other.



Also, contrary to popular belief, the 2 adjusting screws on a carburator are not the screws for air and one for fuel. Both are for fuel.

Answer 3

Polaris Indy Trail

Answer 4

unless you have a gage to balance the carbs with you may make it worse than it is already if you try to adjust those,i own a 2000 model polaris and when it started doing this we got the carb out so bad that it wouldn't start,if you do try it, run it in until it stumbles then run it back out 1-turn,that may correct this problem,if not it may be time to rebuild the carbs on it,good luck.