Thread size for 1910 sediment bulb

[Tbird]

I need to clean up some threads on a 1910 sediment bulb. What is the thread size for the hole where the fuel shut off valve screws into? I know the shut off valves had two different size threads on each side that almost look identical. Thanks!
Mike

[Scott_Conger]

The female fitting in the side of the sediment bowl will be either 1/4 or 1/8 NPT (I do not recall which, but they are dramatically different in size and cannot be confused). Because it is a tapered thread use great caution to ONLY clean the threads and do NOT cut them deeper. #2 Permatex or Gasoila (either but not both) are perfect products to complete the seal and does not require the fit-up to be terribly tight, thus allowing for correct orientation of the shut-off handle when done.

Note: the tapered pipe thread this is NOT a dry seal pipe thread so don't let someone talk you out of a sealant - sealant is critical and has the added convenience of positioning the location/angle of the shut-off valve without having to unduly over torque it.

The other thread on the shut-off is 1/2-18 and is a straight thread and is universally used on all Model T fuel fittings where the felt seal is used. Absolutely NO sealant is used on this union.

If it is of any use to you or anyone else, the elbow at all FORD carbs are: 1/8 NPT on one end and 1/2-18 on the other

[Tbird]

Thanks Scott!
That’s what I needed!

[Allan]

Sometimes the tapered thread on the shut-off valve and in the tank have been abused/over tightened and orienting the outlet is difficult. I once had to thoroughly clean the thread on the valve and tin it wit solder. This allowed the valve to be set at a far better angle for the pipe hook-up. I too use Permatex no 2 sealant for this application.

Allan from down under.

[Mike Silbert]

While Permatex Forma-A-Gasket is a wonderful product, today there could be a new issue.
It is resistant to Gasoline, Oil, and Antifreeze, but it is Alcohol based.
Today with alcohol creeping into gasoline there could be a future problem with using it on gas fittings.

If it is used somewhere that is exposed to gasoline keep an eye on it for possible future leaks.
Time will tell if this becomes an issue or not.
Things would be a lot easier (and smarter) if they quit using corn to make fuel.
Mike

[Allan]

Mike, we are fortunate here in Oz that any fuel with alcohol in the blend is labeled E10, so we can easily avoid using it. It's a couple of cents per litre cheaper than 91 octane, my usual choice. The 2c discount is eaten up by lesser mileage and performance. My T's need all the help they can get, so 91 is the go. The 98 octane needed for some hi-spec cars is 15c or more dearer than 91.

Allan from down

[Mike Silbert]

Allan,

Pumps in my area are required to be marked if they have alcohol in them.
But sometimes it simply says "May Contain Alcohol" or "Alcohol Up To 10%"
They also keep playing with the mixtures having Summer Blends and Winter Blends so you are never sure exactly what you are getting.
There are places that sell alcohol free fuel but they are rare and not in all areas.
It is difficult or impossible to totally avoid around here, especially when you are out touring.

I wish it were different but I can not change the way it is.
I just have to take precautions and keep an eye out for problems.
Mike

[TRDxB2]

While Permatex Forma-A-Gasket is a wonderful product, today there could be a new issue.
It is resistant to Gasoline, Oil, and Antifreeze, but it is Alcohol based.
Today with alcohol creeping into gasoline there could be a future problem with using it on gas fittings.

If it is used somewhere that is exposed to gasoline keep an eye on it for possible future leaks.
Time will tell if this becomes an issue or not.
Things would be a lot easier (and smarter) if they quit using corn to make fuel.
Mike

CONFIRMED!
--

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https://next.henkel-adhesives.com/us/en ... 53476.html
Loctite 518 is highly resistant to gasoline and various fuels
.As an anaerobic gasket sealant, it is designed to create a flexible, solvent-resistant seal that will not tear or decay, making it suitable for applications involving fuel exposure.
Key details regarding Loctite 518 and fuel resistance:
-Performance: It provides excellent resistance to gasoline, diesel, and motor oil.
-Applications: It is frequently used to seal rigid metal engine casings and gearboxes.
-Compatibility: It is effective on aluminum, iron, and steel flanges.
While highly resistant to fuels, it should not be used in systems containing strong oxidizing materials, such as pure oxygen or chlorine.

[Scott_Conger]

Loctite 518 is specifically made for flange-type gasket creation - It is not designed for pipe fittings and thus, I would NOT use it for NTP fittings

If you simply MUST spend more money on a Loctite product, then spend it on 545 which is specifically made for pipe fittings and is fuel and alcohol proof

The added bonus to any Loctite product when used on brass, for those hell-bent to spend more money than necessary, is the encouragement to use yet another expensive product in conjunction with it - that being a Loctite Activator

I suppose it's a fact of life that much good advice on the Forum - advice with decades of use, experience, and success to support it, often has a way of becoming as worrisome as a lit fuse on a stick of dynamite. The topic then becomes centered around the imaginary dynamite. I don't know why driving a 100 year old car with no brakes in modern traffic is nothing to worry about, but the risk of a failure of a sealant is...a sealant with a nearly incalculably small area of exposure to a fluid containing a small percentage of alcohol. If that's the case, then never fear, there is an expensive, Model-T-owner-worry-resistant product called Loctite 545 as mentioned above.

In my prior posting, I mentioned that I typically use a very inexpensive tube of Permatex #2, and in 40 years have had zero failures on fuel related lines including use on Model Ts for the last 20 years during the "ethanol years". The very fact of it being cheap should appeal to most "T" owners, even if it didn't work at all. For those who equate "spending money" with "success" then as mentioned, there is always Loctite 545 which is an outstanding product which I have also used with equal success and under far harsher environments.

Lots of things to worry about in life, I suppose. This isn't one of them.