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Tips

Weeping fuel pump fix

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Aoha Ed,

As Randall & Geo have said, the brass compression sleeve is the thing that makes the seal against the inside flare of the pump outlet. Much like the flared end of a brake line causes a seal. The nut ony needs to be tightened enough to crush the brass against the pump. Continuing to tighten will only lead to worry about stripping the threads in the pump.

If you have recently removed that connection from the pump, it is possible a small bit of dirt may not allow a good seal, or the brass sealing surface was nicked.

Teflon tape on the treads will not seal the fitting IMO. Perhaps a turn or two around the compression sleeve might work. An alternate possibiity is a fuel resistant O-Ring inserted in pump outlet to seal between the pump and the compression sleeve.

Good Luck and Merry Christmas.
 
You could also replace the compression fitting with this. It's barb'd on the fuel line end. A good hardware department should have them.
FuelpumpFitting.jpg
 
Hey Randall you mentioned the olive is no longer available. Is that the olive with the square or flat back?
Steve
 
sp53 said:
Hey Randall you mentioned the olive is no longer available. Is that the olive with the square or flat back?
Click to expand...
Yup, that's the one.
 
bigjones said:
TR3driver said:
What filter? Do you mean the brass screen above the sediment bowl?
Click to expand...

Yes, that's the one.
Click to expand...

Hmm, I can't see why removing the screen would make any difference. The seal in that area is supposed to be between the glass sediment bowl and a lip just outside the screen; the screen itself is effectively entirely inside the fuel cavity. I'm guessing you also replaced the seal and that solved the problem. The original cork seals do have to be replaced from time to time; although the 'rubber' seals from TRF seem to hold up much better.

And you're right, the original TR3 pumps had a screw and clamp to hold the valves in place; nothing was staked. The only pumps I've seen with things staked into place were aftermarket replacements (though certainly the factory might have started doing that later on). If I was overhauling a pump with the valves staked, I think I'd probably try to fabricate a clamp instead.
 
Just back from Christmas in the Richmond area (we got the tail end of the "blizzard" that went up the east coast!). Many thanks for all the input on my fuel pump weeping problem. I had a smiliar problem with one of the brake line connections and had to replace the the compression connection as no tightening made any difference. I'll try some of the suggestions, starting with the least impact (loosen, wiggle the pipe, tighten again for possibly better connection) and then move on to stronger medicine.
 
Yes for sure do the wiggling as you tighten and you might find that you can fab or modify an olive fitting if you feel that your fitting is not getting enough threads as it pulls the olive into the seal.
Steve
 
Thanks, Steve.

I've also purchased some fuel resistant o-rings the right size for the fuel pump, in case the wiggling doesn't work.
 
I had the exact problem with my tr3 and as described the olive is the culprit. After replacing the pump I decided that I should go ahead with a new piece of fuel line and of course the new olive. I did the file off the ends of two of the easily available olive (ferrule). File two of them down to where the flat part starts on both. Place the ground edges together as you put them on the line. The nut won't tighten down as far as it did originally which is what you want. It seems to have worked for me. I did have to tighten just a bit more after running it a while but, seemed to seal.
 
I posted this very question a while back; this will be my first fix for the New Year!
 
Well, there is a cheat that works at times. If you have any Locktite PST laying around, a skim of that on the ferrule (olive) can seal things up. Ask how I know.
 
Bret,

Many thanks. Turns out I do have some Locktite in the garage.

I am going to start by taking the pipe off and inspect it carefully before I do anything else.

A friend has told me that "Such fittings force a flare onto a cone, so there's no face that a gasket (o-ring) can seat on. What happens is that the flare isn't quite even (often they're formed by hand, with a tool) so the seat isn't perfect."

ferrules.... olives... flares... Looks like I need an illustrated dictionary.
 
LexTR3 said:
... All this talk of a ferrule (olive).... Was ist dat? Is it the same thing as a "flare"? If anyone has a photo of a pipe with a ferrule (olive) or a proper flare, it would -- as they say -- substitute for a thousand words.
Click to expand...

It's a compression fitting. The "olive" slides on the tube, and then gets compressed by the fittings. Here's a picture of how it's set up. The only difference in this pic and the one for the TR is that the male and female fittings are switched around.
 
index.jpg

This is the style of ferrule/olive that we wish was available. the ones that are available have much smaller flat surface at the circumference. And they are shorter end to end so the nut bottoms out before the olive seals the connection.
ferrule.jpg

This is a picture of an olive that has been compressed to seal the connection
flare.jpg

This is a pic of a single flare used on a different connection i.e. brakes all thought it is usually a double flare a little different than this one.
 
Eric,

Many warm thanks for the information and especially for the photos. Now I know exactly what I'll be looking at when I remove the pipe from my fuel pump to (a) examine it, and (b) decide how I might keep it from "weeping."
 
I see that neither Moss nor TRF have two key hoses/pipes that attach to the inlet to the fuel pump. The fuel inlet pipe (Moss #588-450) and the fuel tap to pump inliet pipe hose (Moss # 588-475) are not available.

Does anyone have an idea where these may be available or what could be substituted for them? Mine are "OK" but would be better to replace them, if possible.
 
Your local flaps will have steel line. I don't remember the diameter but some one else will. It will likely be flared already and a small pipe cutter will remove the flare, they will also have the ferrules to effect the repair.
 
If you can live without the short steel sections you can go this route:

poolboy said:
You could also replace the compression fitting with this. It's barb'd on the fuel line end. A good hardware department should have them.
FuelpumpFitting.jpg
Click to expand...
 
For all of you who have given me such good advice, many, many thanks.

I have fixed the problem. And the winner on the "advice" front is Wayne (at trrster 2000). After checking the compression fittings and screws on top of the fuel pump, I discovered my problem was with the cork gasket on top of the sediment bowl.

Now this was a real mystery to me because the fuel was pooling on TOP of the fuel pump, and the bowl is -- obviously -- BELOW the top. Somehow, fuel was migrating UP over the lip of the top and pooling there. (I can't explain the physics of this.)

When I removed the sediment bowl, I found that the gasket was in very bad condition. Fuel has been leaking out and migrating UP onto the top of the pump.

After installing a new cork gasket, replacing the screen, and replacing the bowl, the weeping, seeping, and leaking ended.

There was a little leak around the inlet compression nut -- although it was not contributing to the pooling on top of the pump. I removed the pipe. As you know, there is a little cone-shaped bulge at the end of the pipe that fits into the pump and is held there by the nut. I slipped a very small fuel-resistant o-ring around the cone, between the cone and the nut, and put pipe back into the pump. The little o-ring serves two functions: (1) it helps the nut hold the compression nut inside the pump, and (2) it serves as a seal between the back of the cone and the nut. Bottom line: no more leaks.
 
UPDATE ON WEEPING FUEL PUMP

A week and about 100 miles later and the "fix" is still holding. The fuel pump is dry as a bone. The new cork gasket was probably an obvious thing to do, but putting the small fuel-resistant o-ring in the inlet compression connection was not so obvious. It has worked and saved having to replace the pipe.
 
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