tecumseh/lauson carb leak from intake

JCK

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Fuel leaks out through the carb venturi area. I have replaced the inlet needle, seat/clip, and the bowl gaskets. I have adjusted the float level and the float doesn't seem to have any leak (the is no fuel in it).

This is a Lauson carb No. 632500 (mid to late 1980s) Do these carburetors have another valve internally in them that would cause fuel to contunue to out the intake?
 

glennsjr

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Sometimes if the vent for the float bowl is plugged it will siphon fuel like that.
 

JCK

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Thanks for the info - the carburetor looks clean, but will double check the vent.
 

indypower

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check the float. hold it next to your ear and shake it. if you hear sloshing. it has gas in it which will cause it to sink and not shut off the gas at the needle. Tecumseh had a run of bad soldering of the float halfs.
 

tpolley

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I had the same problem this morning working on a trash picked tecumseh 3.8hp. As soon as I hooked up the fuel tank and added fuel it immediately puked fuel out the intake and would eventually flood the engine. I took the carb off and inspected the float and needle valve twice. I did a Google search and found one article where someone said that the little piece of wire that attaches the needle valve to the float needs to point towards the intake side of the carb. The open end needs to point towards the intake. They suggested that it can bind and stick open when flipped around. I didn't think much about it but I went ahead and flipped mine around. I'll be d**ned if it didn't solve the problem. I let it sit all day, starting it periodically and no more poking fuel.
 

doublel

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I'm still suspecting the seat. Make sure it is in properly if you forced it in to far it will kink or if it isn't in far enough it will still link. Test it by hooking a short piece of fuel line to the inlet. Blow air through with carb upright. Slowly turn over until float seats and you shouldn't be able to blow through it. The float should also set level when you turn the carb upside down. I'm sure i don't have to say this but make sure there isn't gas in the carb when you test it :)
 

mumptia

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check the float. hold it next to your ear and shake it. if you hear sloshing. it has gas in it which will cause it to sink and not shut off the gas at the needle. Tecumseh had a run of bad soldering of the float halfs.

Dam good advice there. :thumbsup:
 
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