So this weekend I finally decided to do something with my failing mechanical fuel pump on my 1988 k5 blazer. When i bought the truck it was a tbi 305, i changed it to a carb 383. So this weekend i swaped the holley 670 (or maybe 650) street avenger with no choke to a holley 770 street avenger with an electric choke in hopes to get this truck running like a fuel injected engine (no more peddling till its warm to get it to idle).
In addition i bought a holley fuel pressure regulator and I hooked up my in-tank fuel pump to the regulator and from the regulator to the carb. this setup works great. I regulated the fuel pressure to 7psi and for two days I could have fooled someone into thinking it was a fuel injected truck. It started on one to two cranks every time no matter how cold or warm the engine was and idled perfectly without touching the gas pedal.
Heres the problem...today i opened my hood and looked at my fuel pressure gauge and it read 0, the truck was still running and i can hear the fuel pump pumping in the tank. So i started turning the adjustment screw on the regulator and with the screw all the way turned in I got 4psi. Yesterday with the screw all the way turned in I got above 12psi. Is this the sign of a pump going bad? This pump is who knows how old, its been sitting in the tank for over a year without being used.
I have a new bosch pump and was going to install it untill I saw the lines coming out of the tank, their extreamly rusty and will have to be replaced if I have to replace the fuel pump. This is the reason why i decided to leave the old pump, it worked when i hooked it to power so i figured it would be alright.
any help would be great.