I was cleaning my air filter, when I noticed a qaurter inch of motor oil in the corner of the air box where the drain plug outlet is. Last Saturday I was out riding it full throttle down a coal road when the motor seemed to bog out, but did not stall. The motor seems to be running alright. Is it possible I damaged the motor and it spitting oil up into the air box? The motor has over 4000 miles on it, but runs strong.

 

Sounds to me like your crankcase is overfull. Could be gas leaking through and overfilling it.

 

Howdy,
I gurantee that you had too much oil in the motor. Had the same thing happen to mine when it was new. They are real sensitive to the oil level. Dont fill it to the top of the mark on the stick. Good luck!!!!!!

 

4 possiblities... if you are getting blow by from your cylinders to your crank case, it will pressurize the crankcase enough to force out the oil, with the mileage on your engine, this could be a possiblity... also, higher rpms, tend to splash out more oil... however, my highly modified motor, turning 8400 rpm, isn't to the point of filling the filter box yet, so you'd have to be running right up to your rev limit to put any oil in the filter box, with the oil at the proper level... however, if your oil level, it at the top fill line, it is very easy with higher rpm's, for it to pump oil into the filter box... the proper fill level, should be 1/2 way between the lines, with the dip stick screwed in... does the oil smell like gas ??? could the carbs have drained into the cylinders, leaking into the oil ( a common problem if you don't turn off the gas shut off religiously ), causing it to become over full...

since you have that many miles on you quad, & you haven't noticed that problem before, I'll assume you don't typically over fill the oil, so, I'd smell the oil, & check the level... if it smells ok, but is to the top fill line, drain it down, to the lower fill line... then do some more high speed riding... if it does it again, then your top end is likely getting to the point, that it needs freshening... IMO, you should do, or have a leak down test done... it shouldn't accererate the wear on your engine, provided a ring is not broken, or some other drastic problem, to keep riding it...

 

Do Prairies crank cases and or top ends vent to the air box? Oil in the air box is common on Polarises that have been flipped or wheelied a lot.

 

FISH... yes, the crankcase vents to the filterbox...

 

you may have been overfilled but my vforce did it and jack meadows told me to unplug the vent hose and plug in
pvc valve and vent it to the ground. never had anymore problems including no oil on the ground.

 

Patrailboss,

Newbeatle has given you very good info. I can tell you that when I had the same problem, I ended up replacing both cylinders, pistons, rings, and gaskets. Mine was not due to wear, but failure by the factory to install circlips on the wrist pins. Bushings from the wrist pins wore grooves in the cylinder walls and allowed blow by. A leak down test will definetely help in determining if blow by is the culprit. For me, oil in the air box was an every ride occurence when the problem got real bad. I was blowing though a quart of oil in a 50 mile ride.[img]i/expressions/face-icon-small-mad.gif[/img] I hope this is not your problem, however 4000 miles is alot. I only had 800 miles on my Prairie when this happened.

Maybe this will be a good excuse to get an FST big bore kit..[img]i/expressions/face-icon-small-wink.gif[/img]

 

Kawasaki are you listening? If you (Kawasaki) look in your Service manual section 2-25 there is information about cleaning oil out of both the 02 and 03 Prairie air filter covers. That means you (Kawasaki) knew that oil was going to get in the air cleaner covers and possibly into the engine. Either way not a very acceptible outcome for the Kawasaki owner. I am a loyal Kawasaki customer (having purchased 8 motorcycles and 2 ATVs) and remain one due to your excellent designs and engineering. Please address some of these issues and use your engineering talent to resolve them.

P.S. While working on the engine crankcase vent why not solve the choke/fuel in crankcase issue. I don't think shutting the fuel off every time the ATV is parked provides an acceptible solution.

 

I had the same problem. I figure I put to much in at the oil change as that is when I noticed it. Could also it be from a clogged airfilter as well? I don't seem to have the problem anymore, so who knows what fixed it - either the new K&N or enough oil blew out!