90 degree brass fitting for feul pump
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 2,337
Likes: 14
From: Norfolk VA
90 degree brass fitting for feul pump
I installed a new feul pump on my 79 vette and the 90 degree brass fitting to the pump leaks and the fitting on the flared feul line that screws into the other end of the 90 degree fitting leaks also. I made this line from 3/8 brake line using the flared end with the fitting to screw into the 90 degree fitting. Both areas leak. Why is this so? If I buy a feul line from one of the vendors will that leak as well?
Instructor
Joined: Aug 2016
Posts: 235
Likes: 28
From: Fort McMurray Alberta
I installed a new feul pump on my 79 vette and the 90 degree brass fitting to the pump leaks and the fitting on the flared feul line that screws into the other end of the 90 degree fitting leaks also. I made this line from 3/8 brake line using the flared end with the fitting to screw into the 90 degree fitting. Both areas leak. Why is this so? If I buy a feul line from one of the vendors will that leak as well?
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
The female fitting in the fuel pump is a 3/8 inverted flare, if you installed a fitting that's NPT there's nothing for it to seat against. The inverted flare fittings are a double flare too, That makes the seating surface double the thickness.
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 2,337
Likes: 14
From: Norfolk VA
This is one of two fittings (the other is on the car is leaking) I purchased from Dr. Rebuild and the other from Zip corvette. The male end of this fitting and the one on the car is 1/4 NPT and it leaks when you fasten it to the feul pump body. The fitting on the right is the one at the flared end on the 3/8 brake line I used to fasten to the female end of the brass fitting this crap leaks as well.
This is a fuel pump from Advance Auto. (my pump is still on the car) Are the threads on this opening and the pump on my car NPT as well? This crap is frustrating. Buying parts that don't work. If this is wrong what type of threads are supposed to be on this fitting?
Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
The pump and fitting look correct, npt threads need to have either pipe dope or teflon tape to aid sealing. Although the inverted flare seals on the flare, it sometimes helps to put teflon tape on the threads of the nut, this helps to reduce friction so the flare can compress more.
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 2,337
Likes: 14
From: Norfolk VA
The pump and fitting look correct, npt threads need to have either pipe dope or teflon tape to aid sealing. Although the inverted flare seals on the flare, it sometimes helps to put teflon tape on the threads of the nut, this helps to reduce friction so the flare can compress more.
Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
Did you flare the line yourself? Look at it closely, sometimes they split in the flare. The new brass fitting may help if the old one has been over-tightened before. Maybe a good flare nut wrench and tighten the ---- out of it!
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 2,337
Likes: 14
From: Norfolk VA
I did flare the line myself but I used the already flared end to fasten to the female end of the brass fitting. The end I flared goes to my feul filter and that does not leak. (go figure) The male end of the brass fitting leaks as well. I used a good line wrench to tighten the brake line fitting.
Last edited by Oldguard 7; Aug 28, 2017 at 07:02 PM.
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Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
That fitting on the new pump does not look like an inverted flare. The 90* fitting in the picture above it looks like a female inverted flare.
(My 69, the pump is also a female inverted flare. I fabricated a 3/8 line to fit. )
(My 69, the pump is also a female inverted flare. I fabricated a 3/8 line to fit. )
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 2,337
Likes: 14
From: Norfolk VA
The male end of the brass fitting leaks after being tightend to the pump and the female end if the brass fitting that the flared end of the brake line leaks as well. I used this pic to show on the 79 what I was talking about. Also the fuel pump on the 79 is longer than that on the 69 (it that makes any difference)
Last edited by Oldguard 7; Aug 28, 2017 at 07:22 PM. Reason: Left out info