Solution for Leaking Fuel Fitting - ZR-1 Net Registry Forums

TX '90 ZR1 · 07-02-2018

I have posted about this issue a couple of times previously. With the help of a couple of forum members I have corrected my fuel pressure leak off issue.
There are numerous places that the system can lose pressure. I separated the system into 2 sections to start.
By disconnecting the fuel outlet on the tank you can test the system from the tank forward (lines, connections, injectors & regulator) for leaks from the tank to the front of the car.
l 001.jpg

This test can be done by regulating shop air. I used 45-50 lbs as it is below the normal operating pressure of the system. Don't want to blow anything up!!
Notice in the pic that my test from the tank forward held pressure.

Next is applying pressure to the tank unit. This will test hoses, clamps and fittings along with the fuel pump check valves.
l 003.jpg

You will notice that pressure was not held when testing the fuel sending unit. Upon removing the sending unit from tank and applying pressure was able to trace leak to the "Y" fitting that consolidates the fuel pump output into the tank outlet. The original fitting is made of plastic and had separated at a molding seam.
The outlet hose is 3/8". The 2 hoses to the fitting from the fuel pumps are 5/16". I was unable to locate an "off the shelf" fitting that would accomodate the 2 hose sizes, and also, the fitting is not a true "Y".
Contacted Carter (Carter200) and he agreed to come up with a suitable replacement. (Luckily he live right down the road from me.)
This comparison photo has Carter's prototype fitting. He has made dimension adjustments to adjust for overall size on additional fittings he makes.
l 010.jpg

I also recommend using submersible rated hose as it handles the turns from fitting to pumps better than regular injection fuel hose.
l 008.jpg

When changing pumps or anytime you have the sending unit out, I would recommend replacing the original fitting with one of these that will not be an issue in the future.
l 013.jpg

This is photo of protype fitting installed. Contact Carter (Carter200) if you need one.

A Safe July 4th to everyone!!

HAWAIIZR-1 · 07-02-2018

Thanks for sharing. Great tech tip!! Now I see why I’m waiting so long for Carter to get my stuff done....lol.

Sent from my iPhone using ZR-1 Net Registry

TX '90 ZR1 · 07-02-2018

Quote:

Originally Posted by HAWAIIZR-1

Thanks for sharing. Great tech tip!! Now I see why I’m waiting so long for Carter to get my stuff done....lol.

Sent from my iPhone using ZR-1 Net Registry

Carter is a great guy and does excellent work.
Well worth waiting for!!

carter200 · 07-03-2018

Quote:

Originally Posted by HAWAIIZR-1

Thanks for sharing. Great tech tip!! Now I see why I’m waiting so long for Carter to get my stuff done....lol.

Sent from my iPhone using ZR-1 Net Registry

Craig,
Working on your items right now. Just finished your center caps and on to the rest of the goodies

HAWAIIZR-1 · 07-03-2018

Quote:

Originally Posted by carter200

Craig,
Working on your items right now. Just finished your center caps and on to the rest of the goodies

Mahalo brah. You know I had to take this chance to bust your balls cuz I love ya!! We’ll talk again soon!!

carter200 · 07-03-2018

Quote:

Originally Posted by HAWAIIZR-1

Mahalo brah. You know I had to take this chance to bust your balls cuz I love ya!! We’ll talk again soon!!

I would expect nothing less my ole friend.

-=Jeff=- · 07-03-2018

What (if anything) will the fuel dot to the metal of either the Y block or the Fittings? and the hose clamps?

TX '90 ZR1 · 07-03-2018

Quote:

Originally Posted by -=Jeff=-

What (if anything) will the fuel dot to the metal of either the Y block or the Fittings? and the hose clamps?

There is no issue with aluminum (the "Y" block) or brass (the fittings) being in contact with gasoline. The hose clamps are stainless, so no issue there either.
A lot of aircraft fuel tanks are made of aluminum with brass connections. They have been working for years with the 100LL av-gas which is much drier (as in lubricating properties) than the fuel we use in our cars.
I have no qualms about using these materials in auto gasoline.
Have a great 4th!

-=Jeff=- · 07-03-2018

Quote:

Originally Posted by TX '90 ZR1

There is no issue with aluminum (the "Y" block) or brass (the fittings) being in contact with gasoline. The hose clamps are stainless, so no issue there either.
A lot of aircraft fuel tanks are made of aluminum with brass connections. They have been working for years with the 100LL av-gas which is much drier (as in lubricating properties) than the fuel we use in our cars.
I have no qualms about using these materials in auto gasoline.
Have a great 4th!

Thanks, I was curious more than anything..

carter200 · 07-03-2018

Quote:

Originally Posted by -=Jeff=-

Thanks, I was curious more than anything..

Jeff,
You know you want one

. Have a happy 4th

07-02-2018	#1
TX '90 ZR1 Join Date: Oct 2017 Location: TX Posts: 2,038	Solution for Leaking Fuel Fitting I have posted about this issue a couple of times previously. With the help of a couple of forum members I have corrected my fuel pressure leak off issue. There are numerous places that the system can lose pressure. I separated the system into 2 sections to start. By disconnecting the fuel outlet on the tank you can test the system from the tank forward (lines, connections, injectors & regulator) for leaks from the tank to the front of the car. l 001.jpg This test can be done by regulating shop air. I used 45-50 lbs as it is below the normal operating pressure of the system. Don't want to blow anything up!! Notice in the pic that my test from the tank forward held pressure. Next is applying pressure to the tank unit. This will test hoses, clamps and fittings along with the fuel pump check valves. l 003.jpg You will notice that pressure was not held when testing the fuel sending unit. Upon removing the sending unit from tank and applying pressure was able to trace leak to the "Y" fitting that consolidates the fuel pump output into the tank outlet. The original fitting is made of plastic and had separated at a molding seam. The outlet hose is 3/8". The 2 hoses to the fitting from the fuel pumps are 5/16". I was unable to locate an "off the shelf" fitting that would accomodate the 2 hose sizes, and also, the fitting is not a true "Y". Contacted Carter (Carter200) and he agreed to come up with a suitable replacement. (Luckily he live right down the road from me.) This comparison photo has Carter's prototype fitting. He has made dimension adjustments to adjust for overall size on additional fittings he makes. l 010.jpg I also recommend using submersible rated hose as it handles the turns from fitting to pumps better than regular injection fuel hose. l 008.jpg When changing pumps or anytime you have the sending unit out, I would recommend replacing the original fitting with one of these that will not be an issue in the future. l 013.jpg This is photo of protype fitting installed. Contact Carter (Carter200) if you need one. A Safe July 4th to everyone!! __________________ Kenny 1990 #442

07-02-2018	#2
HAWAIIZR-1 Join Date: May 2010 Location: Japan Posts: 3,582	Re: Solution for Leaking Fuel Fitting Thanks for sharing. Great tech tip!! Now I see why I’m waiting so long for Carter to get my stuff done....lol. Sent from my iPhone using ZR-1 Net Registry __________________ Craig "ZR-1 NO KA 'OI" "ZR-1 ICHIBAN" 1995 #228 Black/Black with Dunn Heads ZR-1 owner since September 2003 ZR-1 Net Registry Founding Member #0074 NCM Lifetime Member #2048

07-03-2018	#7
-=Jeff=- Join Date: Jul 2007 Location: Bartlett, IL Posts: 7,169	Re: Solution for Leaking Fuel Fitting What (if anything) will the fuel dot to the metal of either the Y block or the Fittings? and the hose clamps? __________________ 1990 Corvette ZR-1 #1051 Watson Headers (2" Primary) - Flowmaster Cats - Borla Catback Late Model IH - Plenum Coilovers - 4.10s Custom Interior NCM Lifetime Member #978