Threads used on Zenith carb
 

Anyone know what thread is used on the cast iron inlet of the Zenith carb?
If it's flare, I don't have the sealing surface inside.....it isn't pipe, I tried that and it seems to be a finer thread. Maybe I'm missing a fitting that goes there.

Re: Threads used on Zenith carb
 

1/2" 20

Re: Threads used on Zenith carb
 

Then I'm missing that part. One side would be 1/2-20 male, the other side would be female flare? Who has it, I checked a few places and didn't see one.

Re: Threads used on Zenith carb
 

The flare would have been a double on the line. Just use a 1/2 20 straight fitting made for the compression ring and compression ring. Make sure the line is only 1/8 inch or less past the end of the compression ring and if you have a small ball type stone clean up the seat in the carb just a bit.
Look for fuel line in Snyder's on line catalog (or which ever supplier you like).

Re: Threads used on Zenith carb
 

I just bought a Dremel 7/16" ball stone from true value. My carb repair book said to use this size to remove the pits where the fitting seats itself. Worked ok.

Re: Threads used on Zenith carb
 

Steel line with a fitting and ferrule used on each end of steel gas line.

Same fitting on sediment bowl as carburetor.


http://parts.modelastore.com/show_Product.asp?ID=3892

Re: Threads used on Zenith carb
 

Bert's carb website explains use of Dremel #911 stone.

There is much more info on rebuilding here also!

http://www.model-a.org/dremel_911.html

Use caution here some castings are harder cast iron some are like "Butter"... go slow and check result often.

Re: Threads used on Zenith carb
 

Go to this site http://modelabasics.com Click on carburetor and you will find all the different threat sizes listed.

Re: Threads used on Zenith carb
 

OK, lets cut through all this and see if I have this right.
If I get a repro line it will come with a 1/2-20 male fitting and compression ring which will thread directly into the inlet pictured in my attachment, right?

Re: Threads used on Zenith carb
 

Correct
Remember what #4 mentioned about the 1/8th rule or it will restrict the gas flow ...same goes on the sediment bulb side

Re: Threads used on Zenith carb
 

Easy way to "set" the 1/8" depth of the fuel line. Thread a 1/2 x 20 bolt into the chamber for the screen. Insert fuel line until it just contacts the bolt. Tighten compression fitting and then remove. Then do the same thing with the other end of the fuel line that would be installed into the sediment bulb. Works for me!

Re: Threads used on Zenith carb
 

An even easier way to set the 1/8" depth is to apply some lock tite to the ferrule ID