Tech Tip Tuesday: Fix Leaking Carburetor

Carburetor Float Needle

You turn your gas valve on and before you know it, you have gas running out of your carburetors overflow tube. The first thing I try is tapping the carburetor float bowl lightly with a screw driver or rocking the bike/machine back and forth to try and get the float to move in case it’s stuck. Sometimes that is all that it needs to cure your incontinent carb, but if that doesn’t work here’s a helpful trick, assuming the float height is already adjusted properly. You’ll need to first remove the carburetor from the bike or ATV and then remove the float bowl. Once the float bowl is off, carefully tap out the pin holding on the floats. The float valve needle rests on the floats so be careful when removing them. Inspect the valve needle seating surface for any imperfections or wear. If there is a band worn into it (even a slight one) then it’s time to replace it. Carburetor Float Needle SeatIf that looks good, take a look at where it seats in the carburetor body. The seat is often overlooked and often times, it’s very dirty. A great way to clean this seat is to get a q-tip and place a light dab of toothpaste on it and stick it in the float valve hole and spin it around on the seat to clean it. The q-tip will probably come out dirty, so repeat it a couple times until the float valve seat looks shiny and new. This is an easy trick that works wonders. Make sure to thoroughly clean the area afterwards to remove all traces of toothpaste before putting it back together.

Most of the time, that will fix your carb overflow issue. If not, make sure the float pivots freely on the pin that holds it in. Also check to make sure there are no holes in the floats (they’ll have gas inside them when you take them out if so). It’s also a good idea to put an inline fuel filter on the gas line leading to the carb to prevent any particles or dirt from entering the carburetor. If nothing above works, you may need to adjust your float height, which we will save for another blog post. Thanks for tuning in!

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