Water in fuel, I think I figured it out!

[Mtnviper]

So last year on a long ride my sled started to miss-fire and run poorly, especially on cold start up. Once I got it back home in the shop, I found that it had water in the fuel. I pulled the tank and drained the old fuel and she was good to go! At the time I chalked it up to getting bad fuel at the gas station on the trip.

Well this year it started to miss-fire again and after changing the plugs, it still ran poorly. Then I got to thinking, you don't suppose it has water in the fuel again? I checked it and sure enough the fuel was cloudy and had water in it again.

Only this time around I know the fuel was clean as I have been only using fuel from the same source and cans as my other vehicles.
Upon inspecting the sled for the source of the issue, I found that the fuel tank vent hose is very long and laying in the bottom of the belly pan. I believe what was happening, is that the belly pan would fill up with powder snow. Then as the snow melted and the fuel/tank cooled down, the vacuum created by the cooling fuel would draw in a small amount of water/melting snow through the fuel tank vent hose.
The fix was to cut off the excess fuel tank hose and secure it with a zip tie so that it's up away from the bottom of the belly pan.
HTH
Bill

 

[RTX]

Good catch.
Hope it solves your problem

 

[Mtnviper]

Thanks RTX, yeah I'm hoping that it does. Probably going to take a few rides to tell for sure though.

 

[RTX]

Ya, it sucks when you have the oddball issues that no one else seems to have, but the good part is you seem to have found something that at least makes sense for your issue.
Keep us posted, im sure you are not the only one this will happen to.

 

[yamadoo]

Great catch and seems to make sense