Quick Tips

Lawnmower Carburetor Leaking Gas? The Quick Fix.

“Didn’t I just fill the gas tank?”, I would ask myself week after week after cutting the lawn. That is, until I finally realized that there’s a gas leak somewhere!

The reason it took so long to discover the issue is that the gas was leaking so slowly that it was actually evaporating and not leaving any trace.

Yes, gas evaporation is a thing! There have been studies on it.

When trying to find the source of the leak, I started at the gas tank. Then I worked my way down through the fuel line, past the fuel filter and then right behind the air filter box where the carburetor sits.

Yep, My Carburetor is Leaking

Bingo! When I reached my hand behind the air filter box, I could feel that the carburetor was damp with gas.

My first thought was, “Dang! I’m gonna have to replace the carburetor.” But carburetors are over $100, plus whatever time it takes to figure out how to swap it out.

Next thought, rebuilding the carburetor. I’m sure the kits are inexpensive. But it still involves removing the carb, figuring out how to rebuild it, then replacing it.

Then, the most obvious choice hit me while I was sitting there staring at fuel line. An inline shut-off valve!

Inline Shut-off Valves

Not only are shut-off valves inexpensive (about $9 for 5 of them!), but they’re extremely easy to install.

All you have to do is cut out a segment of your existing fuel line (it’s easiest to do this when your gas tank is empty) and replace it with the inline shut-off valve.

fuel shutoff lawnmower

That’s it! You now just have to get in the habit of shutting off your gas line after each use.

Winterization Bonus

As a bonus, this will not only conserve your fuel, but will make winterization one step easier (as you now have a gas shut off valve).

Just before your last use of the season, turn off the gas line while your engine is running and let it starve itself out of gas.

This will prevent any residual gas from gumming up your components, especially your carburetor.

Or, If you’d rather watch the video…