67 Camaro with no fuel pressure (video)

[cp87]

I have been having fuel delivery problems for awhile now and can't figure it out. This is my 2nd Mechanical pump and after about 15min of run time my pressure drops to zero. I have changed the filter, cleaned the line, checked to see if the tank is clogged and did not find anything. This is very frustrating, any input or suggestions would be appreciated

I want to switch to an electric set up and was looking at the Areomotive SS pump.

https://www.youtube.com/watch?v=Jktatkm8vdA

After 15 min

https://www.youtube.com/watch?v=WuI7oew6VyI

[Vince@Meanstreets]

try removing the gas cap while the pressure drops.

[camcojb]

Originally Posted by Vince@MSperfab

try removing the gas cap while the pressure drops.

yep, sounds like the tank doesn't have a vent, so the longer it runs it makes a vacuum and can't pull fuel.

[cp87]

It does it with no cap at all, i had also thought about vapor locking.

[Vince@Meanstreets]

15 min isnt long enough for the lines to get that hot UNLESS one is resting up against your exhaust.
You have new rubber line throughout the whole system right?
What sending unit/pick up do you have?
Stock or new factory type?
How much fuel is in the tank?

[cp87]

Originally Posted by Vince@MSperfab

15 min isnt long enough for the lines to get that hot UNLESS one is resting up against your exhaust.
You have new rubber line throughout the whole system right?
What sending unit/pick up do you have?
Stock or new factory type?
How much fuel is in the tank?

I have two lines from the fuel cell to the Y block then a single line out to a 3/8 steel line along the frame up to the front fender then it goes back into rubber line to the pump, the pump to the filter then the carb.

no sending unit

about 3/4 full 8gal? if i were to guess

Thinking maybe possible tear in the diaprahm so its pumps air the system?