fuel pump bleed after shut off fc
 

I was wondering if it is common for the fuel pump to bleed down after the ignition is off with a weak fuel pump. Injectors are not leaking and fuel regulator tests fine. Fuel pump tests weak and only peaks at 45 pounds with line plugged. I ordered a new pump because pressure was weak. Am I missing anything on other possibilities of a bleed down. Intake is off and no fuel leaks visible very fast bleed down.

Either you have a leak, or the pump is bad. There is a check valve in the pump that if failing will cause pressure to drop fairly rapidly after the pump shuts off. Perhaps the pump is completely clogged with crud.

thanks, it does bleed down rapidly. I am hoping it is the fuel pump. Could not find any other leaks. Got a walbro on order. will see if that does the trick

if your all stock, the walbro is going to be too much and your going to create more problems than fixing. If you've been running fine on the stock pump, replace it with the stock pump

How fast does it bleed down?

it bleeds down very fast. I have an aftermarket regulator that tests fine. Injectors were just tested and no leaks that I can find.

Release fuel pressure
Connect pressure gauge to filter outlet
Jump the check connector
Turn ignition on for 10 sec
Turn ignition off and disconnect the jumper
Observe the pressure after 5 min
Fuel pressure more than 57PSI
If not, replace fuel pump

the bleed down is not even an important part of the fuel system. peak head pressure and both static and loaded pressures are the important ones.

the pressure hold check valve can actually be problematic if your injectors are leaking.

Thanks everyone for the input. The Walbro works great holds pressure and now it starts a lot easier when cold.