Carvet

Here's my situation. I hooked up a pressure gauge to test the fuel pump. Turn on the key pressure goes to 42 then zero immediately. The car starts and pressure is 34 when running. The FSM states that this a bad check valve. Is this check valve built into the fuel pump?

THE 383 admiral

Yes. the check valve is built inline within the FP. IT is NOT needed. but changes the way you start. most High performance FP do NOT have this check valve. the motor has more power that easily fulfills the prime shot.

34lbs is very low. that is barley enough pressure to supply the injectors. the pessure should be 40 - 43. however, you are lacking the platform & year.

Carvet

Sorry. 1987

aklim

Just to be sure, I'd clamp off the return line and see if it holds pressure. It could also be a bad FPR.

Kevova

This would be a Black 87? Check fuel pressure regulator for fuel leaking at vacuum port. Is there a particular condition your are concerned about? 42 is at the low end of the spec. Fuel pump is in tank. If pulsator is present it should be removed and hose installed in its place, it is not needed.

Carvet

It turns over a little more than it used to, although I hardly ever drive it, but I thought I'd check the pressure and noticed it didn't hold pressure. I replaced the pump about 5 years ago. Sounds like it's time for another one. Yes. Black 87.

Kevova

If you block return line at tank and fuel pressure jumps above the 42 and holds you may want to think about regulator. If you replace pump do fuel filter while you have things apart. Of course driving it like you stole it occasionally makes for a happy engine

aklim

Let's do something like testing before throwing parts at it, shall we?

Carvet

Let's. You coming over?

aklim

If you are in the Milwaukee area, I'll play along. I'm not doing anything serious since the car is running well.

Carvet

Nope. I'm on the east coast. Good beer in Milwaukee!