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Discussion Starter #1
It's on a snowblower, Tecumseh HM80 155296, serial 5323D, # on carb 1099 L54. Carb was rebuilt last year and I really don't want to remove it, gas leaks out when not running but stops when I close the tap below the tank. Other wise runs good. I just replaced the needle valve and seat as on instructions and nothing in the float, I adjusted the float with drill bit method but to no avail it still leaks, everything looks clean no signs of varnish. So I'm thinking if I used a product like Seafoam in the gas tank do you think it might clear up what happening. Otherwise I think I'll just use the fuel shutoff valve when not in use. Anything else simple I can do before I put the cover back on?
 

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Gas leaking is caused by:
1) Needle not seating correctly. Did you replace the needle & seat with a new one? Also, The seat has to go in with the grooved side first.
2) Float does not float.
3) Float set too high. I just make sure the float is paralell with the float gasket flange.
4) Bowl gasket is twisted or not set all around.
 

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Discussion Starter #3
Yes new needle & seat, yes grooved side down, float okay, pretty much paralell and gasket sitting right. All that supplies the float bowl, what controls the gas from entering the carb until needed? I'm thinking if its just flowing into the carb the needle and float is just letting in more fuel.
 

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Yes new needle & seat, yes grooved side down, float okay, pretty much paralell and gasket sitting right. All that supplies the float bowl, what controls the gas from entering the carb until needed? I'm thinking if its just flowing into the carb the needle and float is just letting in more fuel.
The needle & float are what controls the gas entering the bowl. when the gas fills the bowl, the float rises and pushes the needle into the seat shutting off the gas. You could have some dirt on the seat.
Is this left outside or in an unheated shed? If so, your problem could be water in the gas, which freezes into ice. Ice on the needle,seat,or float can cause the problem, too. And it only takes 1 drop of water to cause problems.
 

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Make sure the atmospheric vent to the float bowl is clear. A plugged bowl vent will cause the float to be pushed down by the air pressure and as a result the carburetor will flood fuel.
 

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Discussion Starter #6
Thanks Indy and 30year, I will check the vent tomorrow, and I don't think its a freezing problem as it's in my garage which is above freezing also it runs perfect. Could a sticky metering valve cause this?
 

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Ummm - how about the needle valve clip? Doesn't the open end of that need to point to the choke side of the carb? Or is that just true of a float stabilizing spring when it's used?
Seems to me I had to try the clip reversal trick once and it worked, but it might very well have been coincedental to.

Also my worthless 2 cents about the needle seat. The first one I ever did I put in backwards because the instructions said to "put the grooved side down". Well when the carb is re-assembled the grooved side actually points up, so being the literal person I can be I put the flat side in first so the grooved side would be down when in normal operating position. (OK so I was a little dense on the first one) LOL. Ah the english langauge. Only here can we pare a pair of pears apparently.

>Maytag:wave::cool:
 
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