polaris atv gas in oil

schmidm90 · #1 (**permalink**) 01-23-2012, 07:25 AM

Hey Guys,

I cleaned the carb on my 98 Magnum 425 about 3 weeks ago. It ran great for two days then it became hard to start. I checked the oil level and the first two days it was good. Then when it became hard to start the oil level started to go up. The oil does not really smell like fuel, but that is the only explanation I can come up with. I turn the fuel off every night. Could it be that something in the carb is still dirty and the fuel from the carb is getting into the oil? That would explain why it is hard to start(no fuel) and the oil level rising?

I am going to pull it apart tonight and re-clean everything.

Thanks for any feedback!

factionfx · #2 (**permalink**) 01-23-2012, 08:07 AM

The needle and seat could be leaking on it. So even though the fuel is turned off, there is still fuel in the carb and line that could be leaking past the needle/seat and getting into the engine. We had this on a yamaha breeze a while back. Fixed the leaking needle and changed the oil a couple times and it was good to go.

schmidm90 · #3 (**permalink**) 01-23-2012, 08:19 AM

I will take it all apart tonight and try to clean it. How can I determine which needle/seat is leaking in the carb? ALso any good tricks on how to remove the choke and throttle cables?

factionfx · #4 (**permalink**) 01-23-2012, 08:38 AM

I'm not sure on the tricks fore removing the choke/throttle cables on your bike.. If they are like my bikes, throttle should just be able to unscrew the the slide (and assembly) and place it in a towel, and leave it there. The choke should just be a (plastic) nut, and the whole choke assembly should come out. I'd put it in a towell and leave it there as well.

My float needle had a rubber tip on it. If it is sticking open (like yours) or closed (like mine was; couldn't get it started), it is my understanding that there is no 'cleaning' to it; it just needs to be replaced.

When I say needle & seat, I am referring to the float needle and the seat that goes around it. I don't know of a way to check that they are leaking, I can only tell you that I had mine replaced on the 325 when he pulled it apart to fix the not starting issue. (it wasn't getting fuel, and the fuel pump was working). Parts were about $40 and he was not ripping me off; they are that expensive from polaris.

Mine has been working great for about 1.5 yrs now.

schmidm90 · #5 (**permalink**) 01-23-2012, 04:47 PM

Hey Guys! I took the carb out tonight and am having a few problems. I got the main jet out along with the needle. I have a manual I was following on how to take it all apart and clean it. The one thing I am looking for is the air mix screw that has the o-ring that is causing fuel to leak into my oil. I am attaching a picture of what I am looking at so maybe someone can help me. According to the manual it says there should be a screw in the place where the brass plug with the hole in the center is. It says to turn the screw all the way in and record the number of turns for re-install. If anyone can help that would be great! Thanks!

factionfx · #6 (**permalink**) 01-23-2012, 04:57 PM

Check out the attached image. It is off the Sportsman 500 but the carbs look the same. I think P, L, M, and N are what you are asking for.

schmidm90 · #7 (**permalink**) 01-23-2012, 05:06 PM

Thanks for the picture. Is there a diagram of the bottom of the carb? I am trying to figure out where the fuel could have been leaking into the oil from. The fuel was leaking from the bottom of the carb, I dont think it was coming from the choke. The bowl was empty when I opened it today and I ran it a few days ago, so I think there should have been fuel in it. Thanks again for all your help.

factionfx · #8 (**permalink**) 01-23-2012, 05:16 PM

You're welcome. Attached. 'C' is the needle valve assemble I was talking about in earlier post. That is where my problem was, except mine was stuck closed; sounds like yours is stuck open...

Russ C · #9 (**permalink**) 01-24-2012, 04:07 AM

in your firsttpicture, the brass plug is farthest to left, have to drill it out with 1/8 "bit, dont drill too deep, insert sheet metal screw into plug and remve brass cap, throw cap away, air screw is under brass cap, set at 2,5 turns out, looks like you got the needle and seat and float apart,need to remove both jets and clean with carb cleaner ad compressed air

schmidm90 · #10 (**permalink**) 02-04-2012, 06:08 AM

Thanks Russ!! I ordered a rebuild kit for a Magnum 500 and most of the parts work, but you need to double check each individual piece before putting it in.
It runs great now!!

Thanks again for all your help!