I'll yank the carb and check the float and needle. I am just puzzled that it doesn't also leak when it is not running. I have had many bikes leak over the years from the needle being gummed up but never only when running.

 

I've replaced needle and seats in the 400's that you could see wear points all the way around the seat from the needle that actually looked like a phillips screw driver imprint! It's mainly just this engine and carb vibrates so much and wears out carb parts! Be sure to check the float pin and the float arm itself for wear(wobbly) and replace them if they are along with the needle valve gasket if necessary! In 94 before I started adding the rubber dampeners on the transmissions as a service bulletin, they would just dump a load of fuel down the reeds and bog out at high speeds! OPT

 

I pulled the carb. There was some crud in there so I cleaned it. The float arm and pin do have wear on them and wobbled a bit. I will replace them. In the short term, I closed (crimped) the float arm a little around where the pin goes through and it helped with the wobble. I also bent the tab a little so it stops the flow of fuel sooner and whala, no more leaking. I will still replace the float arm and pin though. Thanks for your help OPT.

 

One more thing. Do I need the foam that goes on the front of the air box or is this overkill filtration.
Mine is practically disentigrated.

 

YES, you need the yellow prefilter (traps a lot of fine dust and dirt) unless you are using a UNI foam filter, or a filter with a foam surround as the main air filter in the air box and not the stock paper element filter! OPT

 

Sorry about taking so long to reply, but as it turns out no I haven't found a "fix" for it yet. I put a complete kit in the carb, order a new rubber isolator for under the carb and installed, adjusted EVERYTHING from where it won't run to there's gas going everywhere and still nothing. I finally just took the overflow hose that is at the rear of the carb and tucked it up behind the brake line that runs to the rear brakes so if it did (not really possible) need to run fuel out it would still be able to (instead of sealing it off). I haven't had any problems with it since and I'm not losing any fuel either but I know it's not "right". I've given up, but if you do find some sort of fix I would greatly appreciate the information!

 

I would bend the tab down a little more than you normally would to stop the flow of fuel sooner. You need to find that happy medium where it still runs and is not fuel starved and where it does not overflow. As OPT stated, this engine shakes a lot and it is tough for the float and needle to seat properly to shut off the fuel. I also crimped the float closed a little around where the float pin goes through to reduce the possibility of the float to move around some. It helped on my quad. If all else fails, you may just need to get another carb.

 

I tried pinching the tubing that the pin runs thru also, but nothing worked... and like i said I bent the tab in .020 to .030" increments from doesn't flow at all, all the way up to fuel flows out of the carb when the fuel in turned on and none of that worked. I replaced EVERY part in the carb and it still does it a little bit when the hose is hanging and when the motor is coming back down to idle. I'm planning on either a rebuild/upgrade or a complete big bore kit in the next year or so and both will require me to get another carb so I can't justify getting another one now since it's working fine with the tube pulled up high.

 

Still does it a little bit "when the motor is coming back down to an idle"! This is when the engine shakes the most and fuel splashes up to the overflow. You would think the counter balancer would help negate vibrations to stop this, but doesn't!. Even with the carb dampener that Polaris came up with,still didn't stop some from dripping,but it at least stopped the bogging problem that I had to deal with on a bunch of em!I'm beginning to think that if Polaris had solid frame engine mounts instead of rubber maybe this would have helped at least on the dumping fuel and leaking problem? Good luck with the rebuild/upgrade! OPT