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Leaking fuel pump connections

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djwoody

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My fuel pump has been oozing gas onto my garage floor so this weekend I decided to replace it.

Removal was pretty straight forward and I discovered the old pump had a slight crack in the glass sediment bowl. Connecting up the new pump went smoothly until I tried to reconnect the fuel lines to the inlet and outlet. This is a simple compression-type connection but I was not able to get either side to seal. I even tried some plumbing teflon tape on the threads to try and get them to seal but no luck.

How do I make these connections leak-proof?
 
Sealing the threads is no good. You've got to get the compression fitting to compress against it's seat in the pump.

You could try to shorten the end of the fastener so that it will pull a little deeper into the pump and put more pressure on the compression ferule against the seat. You may also have to shorten the end of the pipe as it may be bottoming in the pump and not allowing the ferule to seat...or.....cut the hard line back and put a new length of pipe with a new ferule into the pump and splice the two pipes together with a new double ended compression fitting.
 
Hey, thanks for the tip, Jeremy. I'll add a few of those to my next order!

Looks like they also stock that funky nut (to adapt the 1/4" hard line to the 5/16" pump outlet), PN 60176.

Those numbers are not in the TR3 SPC, I'll add them to my PDF copy.
 
Thanks Guys,

I guess new compression fittings are in order.

Jim, I assume by what you're saying the ferule needs to be flush with the end of the pipe??? I think there was about 1/16 to 1/8 of an inch of pipe beyond the edge of the ferule on both the inlet and outlet. I tried to adjust them but they wouldn't budge. Sounds like the cause of leaking.

Here are before and after shots - you can see how much the old pump had been oozing! You can also see how I've started rounding the nut on the inlet compression fitting.

FuelPump-old.jpg

FuelPump-new.jpg
 
No, it's OK for the pipe to protrude somewhat from the end of the ferrule. 1/8" is fine.

The usual problem is that the commonly available ferrules (the ones that are tapered on both sides) do not fit properly. The pump & nut were designed to be used with a "special" ferrule that is full diameter on one side (which goes towards the nut). The double-tapered ferrule goes up inside the nut to some extent, which allows the nut to bottom in the threads before it crushes the ferrule properly.

You may be able to get it to seal by carefully filing away the last thread of the nut (leaving a longer unthreaded portion sticking out). Mine was already rounded, so I made a new longer nut as a lathe project.
 
Don, when I purchased the car (about 20 months ago) it came with a box full of parts that the PO never got around to installing. The pump was one of those parts but it was in a small box together with an instruction sheet from Moss so I can only assume it was ordered from Moss.
 
This is a topic that surfaces periodically, which demonstrates that it is a pretty common problem.

I have read that new, reproduction fuel pumps don't connect well with the existing input pipe. I had this problem and solved it with gasket sealant two years ago, but I suspect that my "fix" is only temporary.

The advice given above looks like a possible "permanent" fix, but for us who are novices at this, some photos or illustrations would really help. For example, it would be a great help to have illustrations for the following:

"You could shorten the end of the fastener so that it will pull a little deeper into the pump." (drawing of where to shorten the "fastener") .... or....

"You may also have to shorten the end of the pipe as it may be bottoming in the pump and not allowing the ferule to seat..." (a drawing or photo?) .. or ..

"Cut the hard line back and put a new length of pipe..." (a drawing or photo?)

If the solutions described above are, indeed, true solutions -- and I suspect they are -- having a little more visual guidance would probably serve for all the future times that this problem is discussed. I realize that supplying such illustrations goes above and beyond what is needed by many, but it sure would be helpful for some.

Just a thought....
 
Another thought is that THIS is a problem and I wonder if Moss is working on it.
If TRF has the correct ferrules, why are they not being supplied with all pumps.
You guys who have had a problem,...have you ever contacted Moss about it?
 
Thanks all. There is some very useful info here which I think should help me solve the issue. I didn't realize it was such a common problem.

I'll report back when it's fixed so that others can benefit as well.
 
dwwoody,

Looking forward to your report. If possible, could you photograph the steps you take to fix this problem and post them with your report. It would be very helpful, indeed.
 
The latest pumps out there (I think) have an extra aluminum adapter piece on both inlet and outlet, probably to get a better seal - I put one on for my rebuilld, I'm not overly fond of it because it makes getting the original line back on pretty difficult - but it did seal for me.
 
<span style="font-weight: bold">So here's my report back:</span>

I removed the fuel line which connects to the pump inlet and filed the ferule ridge down to make it slightly flat. This allowed me to screw it into the pump inlet further and seems to have stopped the leak.

This is the fuel line and ferule before filing
FuelPump-Step1.jpg


This is the file I used
FuelPump-Step2.jpg


This is the ferule after filing
FuelPump-Step3.jpg

FuelPump-Step4.jpg


This morning I went for a nice country drive (Victoria day long weekend in Canada) and found this perfect garage as a backdrop to a photo
TR4A-RusticGarage.jpg
 
djwoody,

Many warm thanks for the report and the great photos. Is the fix still working? If this indeed works, you have solved the problem for many others. Again, many thanks.
 
Hi Ed, yes the fix appears to be permanent. I did it on Saturday and went for a long drive yesterday and all appears to be dry. One thing to note is that I filed the ferule very gently turning the pipe constantly to ensure that it was as even and as smooth as could be. You don't want to over do it.
 
I shoulda bought that car :smile: Looks great Dion!

Cheers,
Tush
 
Thanks Tush! I think you did pretty well with the TR250 you picked up instead :~)
 
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