Leaking fuel pump fitting
Hotshot
Joined: Feb 2004
Posts: 10,756
Likes: 2,588
From: The Shenandoah Valley
I'd use a line wrench on the nut while holding the hex on the fuel pump with another line wrench. The time for that may be past, might need to put a new nut on the line ... or whole new line.
When you change fuel pumps and reuse a fuel line, it's just like putting a new one on, it needs to be tight and an adjustable or open end wrench is bad for those fitting nuts.
I figured was an all metal line to the carburetor. The rubber I figure, goes to the fuel line mounted on the frame.
When you change fuel pumps and reuse a fuel line, it's just like putting a new one on, it needs to be tight and an adjustable or open end wrench is bad for those fitting nuts.
I figured was an all metal line to the carburetor. The rubber I figure, goes to the fuel line mounted on the frame.
Lead Driver
Joined: Jul 2017
Posts: 9,577
Likes: 1,161
From: San Jose, CA
No guarantees with old fittings. But, first thing I would do is make sure it’s not dripping down from the rubber hose above and making it look like the fitting is leaking.
Then I would loosen it, remove it, inspect the flare on the end of the tube and the cone seat on the inside of the pump to make sure that both are clean and smooth. No burrs or debris.
Then put it back together and tighten it down pretty good. Sometimes you have to loosen and tighten, loosen and tighten, loosen and tighten, to to re-seat a flared end.
One potential problem I see, though, that might be insurmountable, is that from here at least, that tube looks almost kinked as it enters the fitting.
If that’s the case, it may never seal again.
But it’s worth messing with before you have to replace it.
Then I would loosen it, remove it, inspect the flare on the end of the tube and the cone seat on the inside of the pump to make sure that both are clean and smooth. No burrs or debris.
Then put it back together and tighten it down pretty good. Sometimes you have to loosen and tighten, loosen and tighten, loosen and tighten, to to re-seat a flared end.
One potential problem I see, though, that might be insurmountable, is that from here at least, that tube looks almost kinked as it enters the fitting.
If that’s the case, it may never seal again.
But it’s worth messing with before you have to replace it.
Fleet Mechanic
Joined: Dec 2007
Posts: 1,504
Likes: 339
From: Wildwood Pa
There's been a lot of chinese fuel pumps made with issues where the fuel line hooks up. No matter what you try, you cannot stop them from leaking. I've heard that the GMB brand of pump are made in Korea & don't have the leak issues.
Moderator & parts slinger
Joined: Feb 2007
Posts: 50,146
Likes: 5,783
From: S/W Missouri, Polk county
The B nut threads and wench flats looks to be pretty beat up. Are you sure the flare on the end of the metal tube is what you need (for the flare) inside the fitting you put the metal pipe in?
Always better to test connect when it in the work bench. Like having a spare short piece of metal fuel line and the correct B nut and to a test fit. And then chase the threads with a tap while it is on the work bench.
Since it looks to be leaking where the metal tube is coming out the B nut, IMO you do not have the nut tightened down enough to press the 2 flares together. Tighten and then try but with the wrench flats work out, you are almost at vice grip mode. Then get a new B nut and cut a bit of the line and re-flare it.
When connecting a metal flare line to a fitting, always 1st make sure inside the fitting is the correct type for the flare you are putting in it. And if they are correct push in and hold the line seated until the b nut is tight.
Always better to test connect when it in the work bench. Like having a spare short piece of metal fuel line and the correct B nut and to a test fit. And then chase the threads with a tap while it is on the work bench.
Since it looks to be leaking where the metal tube is coming out the B nut, IMO you do not have the nut tightened down enough to press the 2 flares together. Tighten and then try but with the wrench flats work out, you are almost at vice grip mode. Then get a new B nut and cut a bit of the line and re-flare it.
When connecting a metal flare line to a fitting, always 1st make sure inside the fitting is the correct type for the flare you are putting in it. And if they are correct push in and hold the line seated until the b nut is tight.
Tuned
Joined: Jan 2019
Posts: 364
Likes: 91
https://www.mscdirect.com/product/details/62249511
Parker flare gaskets...These things work great for any problem flare connection. Might have to get creative tightening that nut.
Parker flare gaskets...These things work great for any problem flare connection. Might have to get creative tightening that nut.
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Laughing Gas
Joined: Feb 2019
Posts: 805
Likes: 145
From: 59701 West Valley Phoenix
Literally just had this problem 2 days ago replacing the pump in my 66 390 Fairlane. I also threaded in by hand, tightened and it leaked. Didn't leak with the old one. Got a 9/16 and took the brand new fitting out of the pump housing, went to Ace hardware and bought another new fitting, connected the line and the leak stopped. Looking at the fitting it appears to be part of the housing? If so another pump may be in your future.
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