Fuel fitting thread identification: 340U

Tue Jan 10, 2006 5:02 pm

Threaded into the fuel inlet in the casting of the Zenith carb on my 340U is a right angle brass fitting with a elongated filter screen on one end. The thread on the screen end of the fitting (into the carb) is 1/8" NPT. Does anyone know the type of threaded fitting on the outside (female) end of the filter fitting? There had been a copper line from the carb to the fuel strainer which I apparently lost before figuring out how to replace it. I don't believe it was a flare fitting, but rather a compression fitting. I also believe the original line was 5/16.

Using the existing fitting, I wanted to reduce it down to a 1/4 tube, into an in-line filter, thru a shutoff valve, and into the gas tank, eliminating the fuel bowl/shutoff. May have to use a 1/4 x 5/15 reducer. All this because I have a really nice SS shutoff I wanted to use, and it's 1/4".

Any ideas on what the thread is coming out of the carb fitting/screen is would be appreciated.

Tue Jan 10, 2006 6:49 pm

I'm not sure on the size, but I just did this with the Cub, and I like it alot better than the fuel bowl. Also I had to use a bunch of different size fittings to get the right sizes...