Fuel Pump Relay

[Zebra]

88 RRC replaced relay twice and they continue to blow I noticed leads to the inherta swithch under driver seat where rather warm as the 3rd relay went out. Any ideas what might be the problem ?

Thought about bypassing the switch under the driver seat as my next step or is it possible fuel pump on its last leg ?

 

[lforgue8]

88 RRC replaced relay twice and they continue to blow I noticed leads to the inherta swithch under driver seat where rather warm as the 3rd relay went out. Any ideas what might be the problem ?

Thought about bypassing the switch under the driver seat as my next step or is it possible fuel pump on its last leg ?

i would bypass the interia sw just to try....also if you havent replaced the fuel pump id do that too..i used to chevy pump and ive got the number posted some where for the napa relay

let us know

 

[kk88rrc]

Napa relay AR-274

 

[ptschram]

Measure the current the fuel pump is drawing.It is not uncommon for them to begin to draw a lot more current as they die.

The really is special as it has a diode in series with the coil, don't just use any relay as it will kill the battery overnight.

 

[MUSKYMAN]

Measure the current the fuel pump is drawing.It is not uncommon for them to begin to draw a lot more current as they die.

The really is special as it has a diode in series with the coil, don't just use any relay as it will kill the battery overnight.

they also can draw alot when the fuel filter is plugged but the fuse should blow before the relay burns up.

what amp fuse is in there?...should be 10 amp as I recall.

 

[Zebra]

I found out wrong relay for sure will drain battery so I have replaced with Bosch relays from British Atlantic both have blown. I think I will bypass the switch to see what happens I dont think it will hurt anything since its a device to cut current to the pump in the case of a collision.

Also I did replace fuel filter thinking pump might be straining due to contraints.


Thanks Fellahs

 

[Zebra]

Replaced fuel filter / fuel pump / new relays

Fuel pump relay blows roughly 5 to 10 minutes randomly after running.


When running truck runs great I do feel warmth at the relays while running. I did the jumper wire and ran the truck with no problems for 30 minutes or so.

Any Ideas

George

 

[ptschram]

ECU. My '88 was dong similar things and throwing odd codes. Swapped an ECU and it runs much better now.

 

[Zebra]

Thanks PT

Got a extra ECU to try

Just got out from under the old girl following wiring harness which has fuel sending unit tied in with pump. As I followed it I noticed it looked like harness might have experienced some heat from resignator or muffler as I felt along it I could fell like melted plastic. Why they routed it that way hmmm. Tight spot gonna investigate maybe this is where the problem lies. This can be so frustrating !!!!!!!!!!!

 

[GYM]

Measure the current the fuel pump is drawing.It is not uncommon for them to begin to draw a lot more current as they die.

PT:
What is the "normal" fuel pump draw range?
Thank you.

 

[ptschram]

PT:
What is the "normal" fuel pump draw range?
Thank you.

3-4 amps, IIRC.