So I have a a 2004 Rancher AT, A little background on this goes like this, I was out riding with a friend one day and it just started to run like ****. Spitting, suttering, finally just died... I couldn't really find anything wrong with it (that I could tell, on a county road with minimal tools) I finaly got it running again and made it home. I am a mechanic, so I'm not a complete retard when it comes to diagnosing things out and fixing the problem. I eventually took it to work and started to look for things. What I found was that I had a ton of H2o in the tank. I had no idea how it got into the tank. So I had already wanted to do a snorkel and jet kit, so when I took the carb apart to clean all the water out I installed my jet kit, drained tank, cleaned, dried, and put everything back together. The bike ran good for a while and then after a while the same **** happened again! So first things first I have no freakin idea how this water gets into my tank! no one has access to it to be a vandal or anything, I know the gas is good and the can it clean (new can and same gas I out in my car, and I poured the **** out to see what it looked like). Then after the second cleaning I have a new problem, (SAME SYMPTOMS OF NOT GETTING FUEL). I have a glass fuel filter installed in the line goin to the carb well it seems that when the bike sits it will be completely full of fuel. After running for a while it spits sputters and just runs like ****, but if you pull the choke on it, it will run just fine for a bit (SUBTRACTING AIR = NOT AS MUCH NEED FOR FUEL). Back to the filter.. When these symptoms occur I can watch the filter basically drain of fuel which leads me to my 2 questions.
#1 How the hell does this water keep getting into my tank? ( happens over time, I don't ride every day)
#2 Why would my tank not be able to supply the fuel I need?
Also I have even gone back to the stock carb settings to eliminate that from the equation.

I have also taken the tank out, petcock, carb, everything and cleaned them. The only thing I can think of now is a deteriorating fuel line and maybe a piece has that keeps blocking the flow, hell IDK, I haven't changed the line yet probably will do that tomorrow here at work.. any help would be grealy appriciated. Sorry for the novel I wrote, I just know that the whole story helps with the diagnosis.

 

Todays fuel is crap and will draw moisture because of the ethonol so use a additive such as stabil designed for ethonol fuels. Also make sure the breather line to the gas cap is not plugged and replace your fuel line. I run Sea Foam through my 400 AT and all my quads twice a year to keep the gum out.

 

You may have already done this but the only other thing I can think of is the in-line fule filter. Replace that with a new one. If it were me I would do that while replacing the fuel supply line. Again it seems you have all your bases covered so this is my only thought.

 

Seems like there is two unrelated things going on. One is the water, the other is no flow. First I'd replace the gas cap, or at least make sure it is breathing like papahouse said. But the water thing has me stumped. I mean, I go 2 months at a time with riding my quad and I have no problems. Where is it stored? Is it under a roof overhang outside where rainwater is slamming it?

 

I usually run seafoam once a year, and I keep stabil in it bc I don't ride often enough to keep refueling with new fuel(busier than I would like to be these days) ...
I thought the same thing, I replaced the filter after the second water/gas issue, so it's new...

I agree seems to be two totally unrelated things happening here. I have checked that the cap breathes like it's supposed to (blew through the vent hose with my mouth to be sure) I even took the cap off when I had it in the shop and just let it run, revving and holding it at a certain rpm (like cruising) to simulate riding and bam; same ****! It just runs out of fuel! I had some crap come up and won't have a chance to work on it until at least monday, so I still havent changed that fuel line yet... But I guess we will just have to see. As for storage, it sits inside a 3 sided buildng that I built onto the back of our little mini barn. I used reclaimed barn tin for the roofing, so sure it has a flew dripps here and there when it pours really hard out but it stays pretty damn dry for the most part... IDK what the deal is for sure, like I said I will change that line hopefully Monday. Hopefully thats the problem, but I thank each of you for your response, and advice. I will post the results as soon as I can.

 

Maybe the fuel shut off valve/petcock has something clogging it? Might be worth trying to clean it or bypass it temporarily.

 

Well I got my pile into work and I think I have determined that it's the damn petcock. I have one ordered, so as soon I get it changed I will let you know the results.