no noise from fuel pump 84 cf

gmfan

Member
Joined
Oct 11, 2008
Messages
11
Location
Ft Worth TX
So I'm trying to start my 84 to unload it off the trailer. Car has sat with 1/4 tank of gas for a few years. I don't have any fuel pump action at all. If I pour raw gas into the throttle bodies the car will run (crappy of course).

Is there a fuel pump relay someplace to check?
Is there more than one fuse that controls the fuel pump?
What are the steps to remove the intake pump?

Thanks
 
Yes there is a fuel pump relay. I think it's under the dash. There's also an oil pressure switch on the back of the engine next to the distributor. That thing will switch 12V to the fuel pump if there's adequate oil pressure.

The pump should run for a couple of secs w/ koeo and repeat if you shut it off for 30 secs. It should start running immediately when cranking.

You can can check the pump by putting 12V on terminal G of the ALDL, it bypasses the relay and should run the pump. This is still fused so if there is a prob w/ the fuse or a wire further downstream the pump will not run...or the pump is dead.

Easiest way to check the switch and that side of the wiring is to take out the rubber connector on the back of the engine and jumper the 2 wires for the FP, the 3rd is for the press gauge. Orange should have 12V ign switched , jumper this to the FP wire tan with white stripe. The pump should start running immediately. If not the pump is dead. If it DOES start you have a bad relay and possibly a bad switch. they are wired in parallel so when running the switch takes some of the load off the relay. The engine should stay running even when the relay dies because there's oil pressure. The switch is easily removed, hook a compressed air source to the thing with a rubber hose and hose clamp and carefully blow some compressed air in it, the switch will trip quickly and the pump should start running (with connector connected to the switch of course)

to remove pump, remove gas filler lid and gas bib, poke around in confined area to undo hoses and remove bolts and wiggle, twist and turn the sending unit out

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Yes there is a fuel pump relay. I think it's under the dash. There's also an oil pressure switch on the back of the engine next to the distributor. That thing will switch 12V to the fuel pump if there's adequate oil pressure.

The pump should run for a couple of secs w/ koeo and repeat if you shut it off for 30 secs. It should start running immediately when cranking.

You can can check the pump by putting 12V on terminal G of the ALDL, it bypasses the relay and should run the pump. This is still fused so if there is a prob w/ the fuse or a wire further downstream the pump will not run...or the pump is dead.

Easiest way to check the switch and that side of the wiring is to take out the rubber connector on the back of the engine and jumper the 2 wires for the FP, the 3rd is for the press gauge. Orange should have 12V ign switched , jumper this to the FP wire tan with white stripe. The pump should start running immediately. If not the pump is dead. If it DOES start you have a bad relay and possibly a bad switch. they are wired in parallel so when running the switch takes some of the load off the relay. The engine should stay running even when the relay dies because there's oil pressure. The switch is easily removed, hook a compressed air source to the thing with a rubber hose and hose clamp and carefully blow some compressed air in it, the switch will trip quickly and the pump should start running (with connector connected to the switch of course)

to remove pump, remove gas filler lid and gas bib, poke around in confined area to undo hoses and remove bolts and wiggle, twist and turn the sending unit out

Image1.jpg

Image2.jpg

Image3.jpg

Image4.jpg

Thank you! This is just what I was needing.
 
remove 4 phillips screws and the gas lid comes off then remove the rubber boot around the filler neck, then remove the 6 10mm bolts and disconnect fuel lines from the sending unit and pull it out of the tank.
 
Little update. Got some help rolling the car off.

DSCN6461.jpg


Couldn't let it go so I got into the tank.

DSCN6463.jpg


Guess what the hose connecting the pump to the feed line was broken.

DSCN6464.jpg


NO! Its not broke it's turned to Playdoh! It was so soft I rolled it into a sticky ball.

DSCN6467.jpg


So I got a new hose section reconnected it all and she started right up old gass and all! Idles kinda rough of course but the throttle response is crisp and no engine knocks/ticks no blue or black smoke from the tail pipes. :yahoo:
 
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