67 Camaro with no fuel pressure (video)
 

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

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.

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

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?

try clamping or removing one of the lines to the y block. so one line to block and one line to pump. second thought, remove one line.

Ok, I will try that. I am not sure the purpose of why the Y block is on there, 2 fuel going into 1. Does it act like a vent as well?

Thanks
Chris

it might, if one of the lines is a vent................. :yes: Are you sure both are for fuel?

No i'm not sure, i have never had them off. I assumed both were fuel because of the placement. the lines are side by side with one another, the lines run about 18'' then go into the Y block that's mounted on the trunk floor

Can you post a picture? You want to make sure you get your feed from the correct line.

https://mail-attachment.googleuserco...8OExn48jtqD0xg

Here is a pic of the Y block, 2 lines and 1 line out. I have no idea why it's set up like this.

You need to use the attachment option for the pic to show.

disconnect one line...see which one pours fuel.

I'd get rid of that and go one line to the pump.

Air leak
 

It sounds like you have an air leak somewhere along your lines. try to see if you lines alone will hold a vacuum. Disconnect them at the rear sump (obviously, cap those), then see if you can pull a vacuum on your system. The interior of the lines/hoses behave differently under a vacuum than under pressure.

My customer's 66 'Stang had a short line (1yr old) that was collapsing inside & doing just about the same thing, but at random intervals.