Hello!!!

My usual area of mechanics is class 8 diesels, but this weekend I have a different project. I am working on a 99 Polaris 300 4wheeler, it will run, but not good. As soon as I give it more than about 5% throttle, it will start dying like it is starving for fuel. So far, I have checked Air filter, fuel filter, spark plug, plug wire, and made sure the fuel tank is breathing, and all are ok. It has that oil injection system that I am not that familar with.

If anyone has any insight in the situation, any help would be greatly appreciated!!! THank you in advance!!!

 

what color is the plug when u pull it out if its white its runnin lean....if its wet its running to rich and if its a darkish brown ur running right in the middle ......maybe the carb needel is set rong or ur carb is really dirty

 

plug was a little damp when I pulled it out, but I figured that was from me messing with the throttle trying to keep it going. I found 1 adjustment screw on the side and that seemed to be for engine speed, and that seems to be about right. I didnt know if there's another adjustment for mixture or anything for that oil injection. Also I have a couple of small hoses that arent connected anywhere, are these breathers of some sort? I ran out of tinkering time tonight, but I'll be back at it first thing in the AM. If anyone can explain the oil injection to me, I would appreciate it imensely. Thanks again!!

 

are u talking about the screw thats on the side of the carb because if so thats the idle screw.....soundt to me more like ur needle is messed up or the jets are plugged......are the hoses that ur talking about comeing off of the carb?? if so one is a vent line and one is a vacume like i belive.....some one correct me if im rong

 

it sounds to me like your needle is messed up. this happened to my friends quad and it would idle but die when he gave it gas

 

Thanks for all the help. I took the advice of looking into the needle and upon getting the carb apart, I found great gobs of yellow-ish sandy crud coating everything in the bowl. I'm going to try to get it all cleaned off, but as nasty as it is, it wouldnt suprise me if I need to get a new carb for it.

Thanks again for the help, I'll post my results

 

since you got the carb apart check the needle. look for brass color on the needle. with sand in the carb its like having sand paper on the needle. i wold proubly put a new jet needle in. also the rubber boot connecting the carb to the motor make sore the bolts are tight and no cracks or holes. that will also make the bike run like the proublem you have. not ehough fuel for the air going in.

 

im gueesing the carb had old gas that turned to varnish. clean the carb thoughly and there should be an air screw as well as the idle screw to set at around 1 1/2 turns to start. make sure the float is level and clean.

 

Just an update, but I dropped off the Carb to get rebuilt, new jets, needle, cleaned, etc. The local dealer can have it done by tomorrow AM and it was only another $20 to have it done and be garunteed to work, $20 well spent IMO.

 

What's a class 8 Diesel??? Just curious...