Isn't there a manual fuel shutoff valve at the bottom of your gas tank where the fuel line from the tank to the carburetor attaches to the tank? I have had a slow leak on mine for years and just close the manual shutoff valve when I am done tilling.

Here is a picture of bottom of a tank with the shutoff on the left.

Yes there is the shut off valve from the tank. My leak is at the bottom of the carburetor bowl. I have to turn of the valve and let the engine run until it shuts off to avoid dripping gasoline.

Can you share a Picture of your carb or a link that will show it??

there should be a gasket, usually fiber? type. they get hard/brittle and leak around that bolt.

Thanks ! Do you know if the gasket should go above, or below, that flat metal bar coming from the air intake tube ?

looking at the pic, it looks like something in between the bracket and carb? do you have model # for your tiller or engine #, make hp? a diagram is probably online.

I have that updraft carb on my model 23. If you leave the gas open with the motor not running, does it constantly leak?? If Yes, like mine, inside the fuel mix assembly is a tube?!?! piece that runs up across the air passage to near the top of the carb. This brass piece has a tapered area as a seat that is supposed to seal but i could not ever get mine to seal after 3 tries. The fuel leaks past this seat inside the carb and down to the screw thus the drip, drip, drip.

You can try tightening it - the nut just above the fuel mix screw remove that then get a flat screwdriver bit - not a plain flat screwdriver(it is tapered, u want sides parallel bit) and try loosen\reseat the part. I tried gasket materials with no luck. I just live with shut off the gas.

IMHO, do nothing except shut off the gas at the tank and run dry. You should do that anyway with today's ethanol polluted gas. Those updraft carbs are pretty simple to rebuild, kits are available, but not cheap. If you do go into it, you'd better have new gaskets ready.

Here's a link to "carb rescue" never used them myself, but have read some very good posts about them on other sites, if you're not comfortable rebuilding it, send to them, you'll get back a "new" rebuilt carb. I think they also have the kits and other parts if you feel like tackling it.

http://www.carbrescue.com/intro.html

If the carb continues to deteriorate, rather than spending "X" on a rebuild kit and tearing into a 40+ year old carb and find out it can't be rebuilt and you're out "X", buy a Predator engine from HF. They're "ChiHondas or Honda Clone" engines which work very well. I know several folks locally who have used them on log splitters, tillers, go carts, etc. I have a 50 year old John Deer Front tine tiller in the barn which I plan on putting one on. Well, as soon as one of my other two tillers dies....:-) You tube is full of videos of them being used. I'm pretty sure they're a "drop in" replacement on the older Troy Bilt machines. I have a Generac 3750 genset which has one on it, 10 years old and starts on the first pull and is very reliable.

https://www.harborfreight.com/65-hp-212cc-ohv-horizontal-shaft-gas-engine-epa-69730.html

Good luck,

Ev

It's just the nature of the updraft carburetor. The Zenith/Bendix updraft carb on my Wisconsin TR10D drips if I don't shut the gas off and let it run dry after each use.