I have a 2000 Prairie 400 4x4 has been leaking gas whenever you fill the tank anymore than 1/4 way. Not like spilling out but when you leave it in the garage, by the next morning it reeks of gas and there is a little puddle. I've noticed a little black rubber hose thats sticking through the drivers side floorboards and it has a clear kinda diaphram looking thing connected to it. I think this is where its leaking from. Should this be connected to something? Or can i plug it or something? Anyone have any ideas? thanks

 

I'm not familar with your bike, but I would say clean the carb and check the float level.

 

The needle and seat are bad in the carb, or you might get lucky and just have a piece of dirt under it. Clean the carb. Turn the gas off with the petcock when not riding , this will prevent wear on the needle and seat.

 

While your at it, go to KAWI and spend 4 bucks on a petcock repair kit. Its the little rubber gasket that chooses the fuel from reserve or normal. They dont last more than a few years in my experience, im on my third now. I HIGHLY recommend a fuel filter. I had a nasty sputtering problem that left me stuck in the woods more than once. It took me a while to trace it down to pieces of this rubber petcock gasket fouling up the carb. A small wix see through filter is very cheap and easy insurance for the yucky carb work your about to do.
The carb is very simple on this bike, so it should all be self explanitory once you get into it. Also make sure your plastic fuel tank isnt cracked. Just a few bolts under the seat and two screws towards the front of the tank cover will allow you to get at and remove the tank for inspection. You must do this anyway to do anything to the carb. Good luck!

 

Oh BTW, that clear hose is the battery vent. Dont plug it! it just carries fumes away when the battery gets shaken from riding.