I have a fuel problem and was wondering if anyone else had a similar problem. I bought a 325 magnum in March. When riding it, if I stopped and shut the engine off without turning the gas off the atv would be flooded out. This didn't happen all the time.... Usually when the machine had been run for a long time and was hot. I took it to the dealer and he found one of the breather lines coming out of the carb pinched shut. He re-routed the line and everything seemed fine. I could leave the gas on when I stopped...I could even leave it turned on over night with no problems.

This past weekend I took it on a long ride...When I stopped after riding for over an hour I could smell gas. When I started the atv after about 5 minutes, it sputtered and was all loaded up with gas. The same thing happened two more times.

There is a breather line coming from the top back of the tank to the steering column. My breather line was pushing enough air into the steering column that I could hear it. It was making a boiling sound. I could see gas in the line below my handle bars and the air was bubbling through the gas. I was riding with 3 other Polaris atv's....I looked at their breather lines.... There was gas in them and the air was bubbling through...however not near as much...not even close to mine....

I'd loosen my gas cap and it would stop. I pulled the breather line out of the steering column to make sure it wasn't clogged or crimped ...I was able to blow though it back into the tank.

It seems like I am building pressure in my tank when the atv is hot and when I shut the atv off the pressure pushes gas into my carb.

Anyone have any ideas???? It seems to have to due with heat.... I've ridden the atv for a month since the dealer found the pinched breather line without any problems. However all of these rides have been really short....

I think the floats are working correctly or the atv would be flooded when I leave the gas on all night.

Any info would be appreciated.

 

I'm not familiar with the setup on your ATV, but on some MX bikes, the fuel tank breather has a valve in it, so that if you tip or flip over, it seals the tank to prevent fuel from leaking out the breather. It is kind of a one-way float type of thing, that is supposed to hold the fuel in the tank. If your machine has that same sort of valve, it is possible it is sticking in the shut position. If your machine doesn't have one of those valves (it is called a 'rollover' valve in a car) I don't know what to say, maybe look for a vented gas cap that would fit at least to see if pressure in the tank is really the problem.

 

Thanks for the response.... I don't think the breather line has a check valve. I'm able to blow air through it both ways.

I'm not suer the problem is with the tank venting... It just seems like that could be the problem.

I was hoping someone else had a similar problem and could point me in a direction.

 

I posted this same problem about a month ago. About three other guys had the problem too. I checked my vent hose out, and then decided to re-route it thru the metal clip that it wraps around on the steering stem. Since then it hasn't been a problem. I saw a guy who makes home made vent caps for Polaris ATVS on e-BAY. He took the stock gas caps, cuts a hole in top, puts a vent hose through it, and claims they are all tested before he mails them out. I don't have a link for them, but if you have the patients to run a search for Polaris on e-BAY, then I'd say check it out.

 

My vent hose goes up through the clip on the steering column and down inside the column...It doesn't wrap around the clip.

I tried using a larger diameter vent hose....which didn't work. (I could not replace the nipple, which was still small.)