Fuel valve leaking

[57j2olds]

Bill,

Thank you very much!

[JasonG]

Great info in this thread. I'm hopeful that tightening my packing nut will solve the same problem on my 1947 Cub.

Out of curiosity, what size Teflon packing do people suggest? There seem to be a lot of options. I've not used the stuff before. 3/32nd seems the most common, but I've found 5/32nd, 1/8th, all the way up to 1/4th.

[Bob McCarty]

I'd use the smallest you can find. With the 3/32" you should only need one wrap.

[Glen]

So here is the valve. It looks like there is a rubber seal in the nut. What can I put in there? Obviously I cannot remove the nut.

Hi, I'm not totally sure, but I think originally the nut might come off the curved shaft. It might slide around the bend in the shaft.
Maybe you need to file the shaft smooth, it looks rough in your pic.

[Dale Finch]

Last time I tried, that nut wouldn't go around the curve. I think someone posted that he straightened it a bit to take it off, but you can pack the white teflon "thread" sealant into the nut without removing it.

NOTE: It is mentioned, I believe in a HOW TO, to use the white stuff, NOT the grahite gray stuff. The graphite packing gets nasty!! Almost like it dissolves, then drips. BTDT!

[Gary Dotson]

If you don't have ready access to the Teflon stuff, I've used dental floss for this purpose. Seemed to work fine!

[staninlowerAL]

If you don't have ready access to the Teflon stuff, I've used dental floss for this purpose. Seemed to work fine!

Agree with Gary's statement. I prefer the waxed type floss, about 3 or 4 wraps is usually enough.

[JasonG]

I have a T shaped handle on my cutoff valve and it was spinning very freely. It's really tight, now. After 24 hours there was still no leak but if that fails I'll probably try floss. I ran the tractor for 40 minutes or so doing some work around the property and it didn't leak then, either. Mildly worried I tightened it too much, but we'll see...

[Glen]

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.

[JasonG]

Started leaking again, bought some small teflon packing, put that in and did about 3 hours of mowing with it, checked later that day - not a drop under the bowl. Let it sit for about 48 hours and it's leaking but perhaps not as bad and perhaps from another spot. The shed is around 1100sq ft and previously it reeked of gas, now there's just a faint smell of it.

The leak seems to be coming from where the sediment bowl meets the fuel tank. I'm thinking of taking the hood/tank off, cleaning it, putting in a new bowl. Also thoroughly cleaning and possibly repaint painting the tractor once the hood is off. Plugs and other things as well, since it's opened up.

Any special thing you do when attaching a new sediment bowl? Do you have to use a new fuel line? Due to the pandemic, I want to order everything I might need so I'm not without the tractor while I wait for shipping.

The tractor is used to mow the lawn and occasionally drive around the property (some hills), haul cut up trees when they fall, etc. Light duty. I very much like the idea of keeping it as original as possible.

Pics of bowl below.

[Don McCombs]

What kind of fuel line do you have currently?

[JasonG]

What kind of fuel line do you have currently?

Looks like standard copper tubing but I'm not sure what size it is.

I was looking at this: https://www.steinertractor.com/IHS3928- ... l-Assembly (let me know if it's not appropriate to link parts; I don't know if this is a sponsor-only forum).

[Don McCombs]

Scrape it a little with a screwdriver. If it is truly copper, I'd replace it with 5/16 steel. You can get a pre-made one from TM Tractor Parts or Steiner or form your own from 21" 5/16 steel brake line.

[Glen]

Hi,
If the gas strainer is leaking at the threads where it screws into the gas tank, and the strainer is not cracked or broken, you can use the same strainer again. Remove it from the tank, clean it, dry the threads of gas, and you can use thread tape, or sealer on the threads, to seal it.
You need thread tape, or sealer that works with gas.

The gas bowl should have a screen above the gasket.
The bowl gasket might not seal if you try to reuse it, if the gasket is old. TM Tractor has a new gasket, and screen.

Below is a listing at TM Tractor for a new gas line. You can look at the pics, they show how it fits.
You have a Zenith carburetor in your pics, it is in the lower pics on the page.

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

[Nelson 634]

That looks awful wet on the bottom of the tank. Maybe you should confirm where the leak is first. Could be tank itself or the connection between the sediment bowl holder and the tank fitting. My suggestion would be to clean bottom of tank. Wipe down with paper towels or rags real good. Then spray with a cleaner of some type and re-wipe . The goal being get it clean and dry. Let set a little while check after 30 min, or so if no leak let it set over night with about a half of a tank of gas in it. Need a little head pressure to confirm a small leak. You can always drain fuel back into gasoline container. As stated above if it is at sediment bowl drain tank remove sediment bowl holder. Install pipe dope tape or paste I've used both types. Just remember to let the paste dry. Also you can remove sediment bowl holder without removing the hood. Good Luck Walter