# Super M and Super A fuel overflows from carb



## fourwheelinj1 (Oct 6, 2011)

We have a 51 Super M and a early 50's Super A and both of them recently had the carbs rebuilt by our local mechanic. The mechanic works at a local tractor dealer as their mechanic full time and has worked for us for years and always easily fixed things but these two carbs have him stumped. He rebuilt the carb on the Super M and it ran good and everything worked fine. Then one day it ran out of gas on us and now the float needle is not shutting off the fuel supply any more so if the tractor is not running the fuel starts coming out the throttle linkage. The Super A that the carb was just rebuilt on is doing the same thing. After the carb was reinstalled and the fuel supply turned on it started leaking. The floats in the carbs have been replaced and it didn't fix it. This mechanic has rebuilt other carbs for us before without issues, but these are causing him problems. Any ideas or suggestions?


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## Country Boy (Mar 18, 2010)

Check for any dirt or debris in the seat area. I have had lawn mower carbs run over after a rebuild, only to find a tiny piece of dirt stuck on either the needle or the seat, holding the needle open. The fact that it happened to the M after it ran out of gas makes me think it is most likely dirt that got pulled out of the tank with the last bit of gas.


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## fourwheelinj1 (Oct 6, 2011)

Yeah the M might be trash the mechanic just hasn't had time to come back to take a look at it again. The A however has been taken apart cleaned and the float changed and it still does the same thing so I don't think trash is the issue there.


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## Country Boy (Mar 18, 2010)

Did the carb on the A leak before the rebuild? Could there be a crack in the housing somewhere? I had a carb on an old (1960s) Briggs and Stratton that had cracked around the screw in seat for the inlet needle. Figured it was overtightened at some point in time. The gas was able to leak past the needle through that crack.

On many carbs, if the air vent is plugged, they can overflow as well. The needle and seat in the rebuild kit may be faulty.


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## FARMALL RON (Sep 30, 2007)

My H you can start it run it and turn it off and before you can get off of it gas is running out of the bottom of it and I have done everthing that know to do too it............Ron


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## caseman-d (Nov 29, 2003)

Check the float level or could be a bad float.
caseman-d


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