MTFCA Forum

Hi All,
I just finished restoring a cowl fuel tank and a sediment bowl, but when I screw in the bowl, it stops in the upside down position. This is after using teflon tape first, then trying thread sealer.
The threads seem good to me; I've cleaned them out with an angled pick. What are my options?
Should I use teflon tape, thread sealer, plumbers putty, ultra black? Any other solutions. Thanks.
John

John, if you can find the right tap, try running it in the thread, a little at a time, and them fitting the outlet. It is a tapered thread,and just a little will let the sediment bowl seat a little deeper. Do not over-do it!
Otherwise, a brass fitting with the same thread, one male external and one female internal, may well seat in a different position, and with two joints, you are more likely to get closer to the alignment needed.

Hope this helps.
Allan from down under.

I am sure everyone has the favorites. After looking at some specifications - looks like Permatex® Aviation Form-A-Gasket® No. 3 is best overall since it can be used in other applications as well, has the highest temperature range too and was the most recommended.
Also like all the others have said do not u se WHITE Teflon tape .

#3 is fairly thin, is brushed on and stays tacky and flexible after cure...great on hoses but I would not use it on a threaded fitting which might not be mechanically tight such as the OP will have with simply a dressing.

I like, and would use in this instance, plain old stinky Permatex 2A paste. It will stay put and the part will stay put. It seals well even if the parts are not torqued to the max and will not fatigue nor attract contamination due to tackiness. It will not leak and can be removed in the future.

Thank you guys. Scott, I like the fact that it will work if all isnot torqued down completely. This sediment bulb only goes to the 3:00 position, so I would have to back it off to get it in the down angle. That leaves it a little loose in the tank outlet. So it should work.
John

I would still use a sealer. There have been a number of discussion where people have had issues in removing the sediment bowl. A Paste (Permatex 2A ) would make it easier to remove down the road.

John

please don't take my advice as a go-ahead to try to seal a wobbly assembly. You will be able to get this installed a little more clockwise than with a bunch of wraps of teflon tape and may even find that it lines up just fine. I'd test it dry without any sealant.

If it is plain too tight by 3:00 to get it to 6:00, and one less turn is just plain loose, stop. Borrow a NPT tap or die and get another 1/4 turn put into either the tank or the sediment bowl.

In any event, my opinion and personal choice for this work every time, is Permatex 2A as I mentioned above.

TRDxB2 wrote: ↑

Wed Jun 16, 2021 11:15 am

I would still use a sealer. There have been a number of discussion where people have had issues in removing the sediment bowl. A Paste (Permatex 2A ) would make it easier to remove down the road.

Agree

Permatex #2 sealer has never failed my on gasoline fittings, like the sediment bulb.

Plus the sediment bulb is tapered pipe thread, so it less prone to leaking anyway, and does not have to be torqued so tightly, just firm seated.

Of course, don't use sealer on the carb or bulb pack nuts, those you remove from time to time. For best results, have found using a piece of 1/4" id soft fuel line hose to replace the Ford felt seal, makes a better packing material there.

Trick too on the repro brass sediment bulbs, they tend to seat fully anyway due to the modern pipe threads, and the shoulder nut rides close to the tank, a very thin open end wrench is beneficial as a thick monkey wrench can wedge there!

TRDxB2 wrote: ↑

Tue Jun 15, 2021 10:43 pm

I am sure everyone has the favorites. This yellow tape specifically says gasoline
Also like all the others have said do not u se WHITE Teflon tape .

Frank

Look again at your posted photo on the Yellow tape, the molded word is GASLINE. , isn't rated for petrol.

Regarding "modern pipe threads" - I had a chat a number of years ago with Billy who took over reproducing the new gas tanks and he told me that the tank outlet castings were tapped too deep by the original producer's hired help thus the reason Snyder's new sediment bulbs want to bottom out ! I've addressed that issue twice by adding a thin layer of solder to the new sediment bulb.

Steve

I really like that idea...it's a winner!

DanTreace wrote: ↑

Wed Jun 16, 2021 2:29 pm

TRDxB2 wrote: ↑

Tue Jun 15, 2021 10:43 pm

I am sure everyone has the favorites. This yellow tape specifically says gasoline
Also like all the others have said do not u se WHITE Teflon tape .

Frank

Look again at your posted photo on the Yellow tape, the molded word is GASLINE. , isn't rated for petrol.

OOOOh glad you caught that I removed it. I am slightly dyslexic, have a terrible time doing SuDoKu puzzles -really!
The specification approved for "gas" is exactly what I tried to not to error on.

Frank, it's not your fault. Blame the goose who decided that liquid petrol should be called gas.

Allan from down under, where gas is a gas.