Fuel valve leaking

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57j2olds
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Re: Fuel valve leaking

Postby 57j2olds » Thu May 14, 2020 6:37 pm

Hello again!

So my NEW fuel valve from TM arrived. I just put it on and it's LEAKING at the on/off handle!

Do I tighten the new nut more even though its fresh out of the box?

No more leaks at the NEW line I just installed.

Help!!

Jim Becker
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Re: Fuel valve leaking

Postby Jim Becker » Thu May 14, 2020 7:02 pm

Are you opening the valve completely? Many partly open valves will leak and it is normal.

57j2olds
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Re: Fuel valve leaking

Postby 57j2olds » Thu May 14, 2020 7:32 pm

I just opened all the way and it looks like its not leaking.

Thanks for that!!

Now - leaking where the line meets the carb! New line!

Any tricks I can try? Teflon? How tight should the nut be?

Sorry for all the posts, just getting frustrated.

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Glen
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Re: Fuel valve leaking

Postby Glen » Thu May 14, 2020 8:25 pm

Hi,
Tighten the nut with the packing just enough that it doesn't leak. Don't tighten it too much, the handle can be hard to turn.
Check when you are tightening it that the handle doesn't turn hard.

Tighten the gas line connections gently, the IH carburetor, and the gas strainer are made of soft metal, and threads can strip.

Sometimes the gas line connections at the carburetor or the gas strainer don't seal perfectly.
I have used a little sealer on them. Take the tube off, and dry it of gas before applying the sealer.
The sealer has to be one that is gas resistant.
You probably should let the sealer dry some before opening the gas valve. :)

57j2olds
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Re: Fuel valve leaking

Postby 57j2olds » Sun May 17, 2020 2:34 pm

The fuel is leaking between the fuel line and the nut. Not the threads...

Any clues?

Jim Becker
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Re: Fuel valve leaking

Postby Jim Becker » Sun May 17, 2020 4:26 pm

The nut needs to be tightened enough to crush the ferule against the tube and the nut. Sometimes it does not crush enough at the torque I'm willing to give the nut at the carburetor. I have been able to use a brass fitting that is the same style as the carburetor inlet. Put the gas line into the brass fitting and tighten it hard enough to finish the crush. Take that back apart and reinstall gently into the carburetor.

The needed brass fitting may already be screwed into the sediment bowl assembly.

57j2olds
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Re: Fuel valve leaking

Postby 57j2olds » Sun May 17, 2020 7:06 pm

Jim,

I'm confused. Sorry. Can you explain?

Lee

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Glen
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Re: Fuel valve leaking

Postby Glen » Sun May 17, 2020 9:27 pm

Hi,
If you are using the original type fittings on the gas line, the sealing rings break off from the fitting when you tighten the fitting the first time, and the ring shrinks slightly, to stay tight on the tubing.

It explains that in TM Tractor's listing for the new gas line.

http://www.tmtractor.com/new/fl/864fp.htm

The carburetor and gas strainer are made of soft metal. If you need to turn tighter than the soft threads can take, Jim suggested using a brass fitting to tighten the fitting into the first time, then the ring will break loose from the fitting, and close onto the tubing.
The fitting has to have the same thread, and interior as the carb and gas strainer have.
Some gas strainers have a brass fitting, some don't.

The sealer can be applied between the fitting and tube, the ring has to be right on the tube, broken off from the fitting by tightening it into the carb or strainer, and tight on the tube.
Slide the threaded fitting away from the end, dry it of all gas, and apply a little gas resistant sealer on the tube at the ring.
Then assemble it again. Let it sit without gas so the sealer can dry some. :)

Jim Becker
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Re: Fuel valve leaking

Postby Jim Becker » Sun May 17, 2020 10:05 pm

Glen's explanation is what I was going for.

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Re: Fuel valve leaking

Postby Bob McCarty » Sun May 17, 2020 10:51 pm

The carb inlet threads are 1/2-20. You can find a brass female compression fitting to use for that initial ferrule seating. Most hardware plumbing sections will have it or something similar.
"We don't need to think more,
we need to think differently."
-Albert Einstein

57j2olds
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Re: Fuel valve leaking

Postby 57j2olds » Mon May 18, 2020 8:56 am

Ok,

I think I get it. I just ordered my 3rd sediment bowl:

https://www.amazon.com/gp/product/B00CY ... UTF8&psc=1

The whole "arm" type is giving me grey hairs. Although same theory with 2 nuts. Hopefully seals better...….

This one got good reviews.


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