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General Tech Fuel Pump Inlet Ferrule Leak

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KVH

KVH

Obi Wan
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I have a new pump and new inlet pipe and compression nut at the fuel pump of my TR4A—so I’m being careful. For a few weeks after installing, I’ve had no leak. But now, of course, it’s leaking very slightly.

My instruction sheet warns against over tightening. Quite frankly, I think I’m close to being too tight. And each slight turn seems to do nothing. And, BTW, I abandoned that fix of using two half-ferrules, filing them even, etc. That seemed eventually not to work so well.

So, my question: When do you folks “stop” tightening that compression nut for fear you’ll just strip the threads in the pump. Is there a good test for feel, or should I just grab that line wrench and have at it? I guess my best judgment would be to try a bit more, maybe another 1/4 to 1/2 turn, then give up and try a new ferrule.

Thoughts please?

Thanks guys.
 
My procedure would be to tighten maybe 1/8 turn and then check it. Wipe it dry and leave it for a day or several hours. You may need to do this a couple times. I have never stripped any threads by doing this. Cross threading likely is the reason for messing up the threads.
Continued tightening tends to deform the 5/16" pipe. Once the pipe is deformed you need to cut the deformed pipe and ferrule off and start with a fresh pipe and ferrule.
Charley
 
THis is how I fix a leaky ferulle,although im sure some will think it is unacceptable.
Take some 3/4 wide Teflon tape,which is thicker than the 1/2"and cut the tape in half to get about a 3/8 wide strip.
Wrap around 3 turns on the front side of ferulle.No tape on threads.
Tighten snug.
Teflon tape is really ribbon packing and works.
Have fun
Tom
 
charleyf said:
My procedure would be to tighten maybe 1/8 turn and then check it. Wipe it dry and leave it for a day or several hours. You may need to do this a couple times. I have never stripped any threads by doing this. Cross threading likely is the reason for messing up the threads.
Continued tightening tends to deform the 5/16" pipe. Once the pipe is deformed you need to cut the deformed pipe and ferrule off and start with a fresh pipe and ferrule.
Charley
Click to expand...
Got it. Thanks!
 
I just posted some thoughts relating to the same issue, but I posted under a prior thread relating to a fuel pump pressure reducer I just installed, in case anyone may find that interesting – – as I think that could possibly be the root of my problem
 
If you are worried about stripping the threads...you are already as tight as you want to go. +1 on remove the connection, clean, dry, and try a bit of sealant. Also, a split ferrule will always leak in a fuel connection. It's called a "compression" fitting because the ferrule is compressed onto the tubing. You need a solid brass ferrule.
 
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