Carb Problem - Float/Needle Valve

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Posted by Andy Hillaker ( on July 08, 2004 at 09:41:02:

In Reply to: Carb problem posted by Joy on 17:29:51 07/04/04:

Joy, I just rebuilt my carb - 3 times over the fourth trying to solve a problem where I had gas leaking out the front of the carb itself.

It turns out that the float chamber is filled from the top and when the float rises - as the level in float chamber rises - it (the float) closes a needle valve in the top of the float chamber. There is no spring or any other assembly. Consequently (and this is what happened to me) when any, and I mean any, small piece of foriegn materian gets wedged in the needle valve and corresponding seat, the needle will get stuck open and gas will continue to flow into the chamber.

During the first of my three rebuilds, the valve was stuck open (becuase the new float was not adjusted correctly). The engine ran great after install, but wouldn't restart as it was flooded.

There are two or three ways to check to see what's going on.

I would first run the engine and while running take off the rebreather and flame arrester and watch to see if the front chamber continues to fill with gas after you rev down the engine.

Then next thing to do is to take the carb off and examine the float and needle valve and seat. This is easier than you might think. You can also get a rebuild kit fom Moyer. ALso, an easier job than you might expect. Spray all of that down well with carb cleaner. Also, make certain the your fuel filter is new - I had to install a new inline filter as well to fix the problem.

Hope this helps

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