Fuel Pump Relay for 1980 to 199* P30

[D_E_Bishop]

I found another maker for the FPR used in 0lder P30's, it is Airtex and the part number is 1R1240. It is an exact replacement for the OEM, TRW 15528707 relay.

Best part is the prices range from $10.00 t0 $21.00 through eBay. OTC sales in Simi Valley, CA @ Aims Auto Supply.

Of course I found these after I bought one at $15.00 + expedited shipping. My RV is stored in Simi Valley, go figure.

[j-d]

Yo! Bud! I was sure glad to be sitting when I clicked on the O'Reilly link and saw $120!!!

Believe I'd be getting a Bosch Relay and Socket



Just have to be a little careful. There seem to be "Bosch" Relays with only 4 contacts, meaning no "back" contact closing an alternative circuit when the relay is NOT energized. OK to use only 4 pins of a 5-pin relay so long as the back contact isn't needed. OP's diagram says it IS needed.

We found where some of the later Workhorse Class A chassis used a "Siemens Relay" that does the same thing but in a different form factor. Carried GM part numbers.

Would still like to know more about the "regulator."

[MEXICOWANDERER]

Dozens perhaps hundreds of long motorhomes have made it halfway up Sherwin Grade on US 395 or Tioga Pass CA 120.

OEM mechanical fuel pumps were NEVER designed to pull fuel thirty some odd feet on an uphill angle. They had to have a safety Unattended Key On fuel cutoff and they chose an oil pressure switch.

All it takes is a chassis Service Bulletin to change designs.

[enblethen]

OP could have a very early 89 that has a carb and electric fuel pump. They used a fuel cut-off relay like this.
Fuel cut-off relay
I do not have a drawing showing how they are wired in my cheap manual. All the drawings I have show the oil pressure sending unit in the wiring diagram.

[j-d]

I think I've got the gist of this. The 454 has a carburetor fed by an engine-mounted mechanical fuel pump. BUT SOME P-30 models have an in-tank electric pump feeding the mechanical pump. OK so far? The electric pump is powered through a relay. The relay powers the pump IF either, driver is cranking the engine, OR the engine is running, determined by oil pressure.
OP believes the in-tank pump isn't running due to a bad relay or not staying running due to an intermittent relay.
A likely scenario, but... Are all filters new or clean, including the little one in the inlet of the Quadrajet? And, is the mechanical pump good?

[enblethen]

Something does not sound right.
In your FPR post you indicate that it is 1989 with a Quadrajet carb, but I find no reference to a fuel pressure regulator being used with a carb.
The fuel pump relay is only shown for throttle body injection and power fed through the oil pressure sending unit. This configuration continued for several years starting in 1988.

[D_E_Bishop]

enblethen wrote:
The fuel pump relay only pressurizes the fuel system for a few seconds, then shuts off.
The fuel pump run and power is ran through the oil pressure gauge.
What is the problem with the system that you feel it is the relay?
Fuel pump relay

Not quite accurate, read my last post here; FPR Post

j-d, I'll let you know when I return home and go to the storage yard.

[enblethen]

The fuel pump relay only pressurizes the fuel system for a few seconds, then shuts off.
The fuel pump run and power is ran through the oil pressure gauge.
What is the problem with the system that you feel it is the relay?
Fuel pump relay

[j-d]

Rectangular but rounded relay, contacts in a row? Or more like a cube, four contacts arranged like a Capital "E"?

Either way, if this works, you're that quintessential Happy Camper.

Let us know how you do...