The sediment bowl on my í27 touring is leaking where it screws into the gas tank. This is a tapered pipe thread. I replaced this sediment bowl a couple of months ago and used some of that expensive aircraft grease which worked for a while but it is now leaking when the tank is over 1/3 full. I canít screw the bulb in any further as it bottoms out and the bulb must in the vertical position. Iíve thought about using fuel resistant Teflon tape if I can find some.
Any helpful suggestions will be appreciated.
I used permatex #2 on mine. Liberal application on the threads hasn't leaked since that was 3 years ago
It should not be bottoming out. I suspect wear (damage from past overtightening?) to either the sediment bulb and/or tank threads.
Thanks G.R., I'll try that.
You might also try rubbing a bar of hand soap into the threads, being careful not to let any bits protrude ever the end. Soap is impervious to gasoline.
Read what Hal posted. What did you replace it with? Looks like the valve is bad or the tank fitting is damaged, cracked, ect. You need to fix the problem, not patch the problem. I have brought a couple of Model Ts that burned down there homes because of a gas leak. Good luck, Dan
Thanks for your comments and suggestions but I need to add some more info. I bought the car in 1988 and the cast iron sediment bulb never leaked until some two or three years ago when the shut-off valve started leaking. I only noticed this when I was working on the carburetor. I stopped this leakage several times but only with limited/short time success. I finally bought a new brass repo sediment bulb which I installed around six months ago. I covered the threads going into the gas tank with some fuel proof aircraft grease. This worked until I accidently bumped the sediment bulb.
Today I took the new bulb off and replaced it with the old one. When the old one is tightened there are clearly two male threads still showing in the pipe fitting. When I screw the new one on there are no threads showing and it wonít go on far enough to get the bowl perpendicular. I no longer think that the bulb is bottoming out but rather that it has run out of threads. I donít think that there is any damage to the tank as the old bulb tightens up just fine.
I plan to go back to using the old bulb and the usual aircraft grease. I see that there is packing listed in the Langís catalog so I Iíll order this along with a few other needed items.
Thanks again, Robert
It's rather disheartening how often the best fix for repro parts is to change back to original Ford . . .
In fairness to the makers of repro parts, too often their only recourse is to "reverse-engineer" parts from a single existing example; often that means the reproduction fits one example OK, but doesn't cover the gamut of original tolerances, so sometimes they don't quite fit or work as original.
Thanks again for your comments and suggestions. I found my #300 reading glasses and went back to look at the problem.
When I reinstall the old sediment bulb it tightens and lines up correctly and three threads still show. When I install the repro it is hard to see how many threads show as several are covered with powder coating. It looks like this extra powder coating is causing my problem. Getting this off would be easy if the repro was cast iron but I think it would be hard to remove it from the brass threads without damaging them.
My plan now is to try to use the shut-off valve from the repro on the original sediment bulb and if that wonít work purchase and replace the packing in the original.
That's a shame the threads are covered like that, perhaps wire brush on Dremel would remove some of the coating and not wreck the brass pipe thread?
Use the correct pipe thread die, carefully only removing paint/powder coat. Tapered thread chasing is 'sneak up on' and stop before any metal is removed. I would never wire brush or file brass pipe threads of anything I wanted to not leak afterward. best, jb
Robert Hoops: Try this and see what happens, wrap the threads with a good Teflon tape followed by the whit pipe dope and slowly screw in the bulb and do not over tighten it and let it set for 12 hours to see if it will leaks
Thanks again to all of you. I ended up doing what I should have done in the first place. I received some small parts from Lang's today, including packing for the shutoff valve. I used the old bulb as the pipe threads tighten up correctly. I brushed some aircraft gasket maker/thread sealer on the pipe threads but I doubt that it was needed. I filled it with gas and there were no leaks and the shut-off valve works just fine.