fuel relay wiring

[lee]

Hi,dont supppose anyone has the wiring digram of the fuel pump and relay, its circuit digram 20 and also the page that lists the components as i dont have these pages in my haynes manual

[Trevhib]

I assume it's in here:
http://www.rtoc.org/files/?path=Technical%20Files/Wiring%20diagrams/

Various fuel related diagrams/wiring in there but not sure if it covers exactly what you need.

Plus some info about the relay itself, here and here:
http://www.rtoc.org/boards/showthread.php?t=19
http://www.rtoc.org/boards/showthread.php?t=4723

[James5]

Fuel Pump relay colours are

Thick red = Battery +ve
Thick white = Fuel pump +ve
Thin black = ground
Thin yellow = ignition +ve
Thin brown/grey = tacho

The relay watches the tacho signal to decide when to switch the pump on and off.

[Matt Cole]

What are the colours of the 3 wires to the AEI?

[R5MJH]

What are the colours of the 3 wires to the AEI?

think grey is tacho matt not sure on rest

[Trevhib]

Matching the list of wire colours in this article (page 2):
http://www.rtoc.org/boards/showthread.php?t=1666

With this diagram:
http://www.rtoc.org/files/Technical%20Files/Wiring%20diagrams/Fuel%20pump%20wiring.jpg

It looks like, M/V (Brown and Green), N (Black), and Bc (White) come from (or go to) the AEI (on that three pin plug). Are they the three wires you meant?

M/V is noted as the output from the AEI to the rev counter.

Is that about right? Difficult to see the diagram properly.

[Matt Cole]

Cheers Trev. Its the three wires (tacho, ign switched live and earth). Thing is, at the fuel relay the colours are slightly different. The Tacho is grey to the relay but most suggest brown to the AEI? I guess it must split off a different colour to the back of the rev counter.

[Trevhib]

I dunno mate. In theory it should be possible to wade through the diagrams and follow the wires all the way along their respective routes. Would be easier if printed out I imagine.

[James5]

Cheers Trev. Its the three wires (tacho, ign switched live and earth). Thing is, at the fuel relay the colours are slightly different. The Tacho is grey to the relay but most suggest brown to the AEI? I guess it must split off a different colour to the back of the rev counter.


What you wiring in Matt is this for a C1j Setup or wiring for your adaptronic?

Grey - Tacho
GND
Positive - Yellow

2pin plug 1 is pink / white this goes to Ign1 on adaptronic

[Matt Cole]

What you wiring in Matt is this for a C1j Setup or wiring for your adaptronic?

Grey - Tacho
GND
Positive - Yellow

2pin plug 1 is pink / white this goes to Ign1 on adaptronic

Yeah it's to wire in the adaptronic. It'd years since I did it. I used a separate relay and connected some of the wiring to the back of the relay. I guess I was only using the thick white to trigger the fuel pump.

[Matt Cole]

Sorted now. Pump now working. Just need crank pick up to respond then job done!

[Matt Cole]

Reviving an old thread. Wiring isn't my strong point so guidance appreciated.

I need to replace the wiring to my fuel pump. I figure the 35 years of use probably wont hold the current i need for my fuel delivery needs. Now, i use a separate relay triggered from my ecu and from memory i 'tapped' into the wiring serving the original fuel relay. Im wondering if i can do away with the original relay completely?

My main question is, do i just run new wiring from my own relay directly to the pump? Also what size wire would be recommended for maintaining a good voltage?

[Ian S]

Does your new setup sense if the engine is running or not and shuts of the fuel if not?

Your new pump might be more efficient and use less current than the 1980's one. You could check the specs on them and compare the current requirements.

Unless the sheath has chaffed or gone brittle, the old wiring should be OK I'd guess but the joins might be corroded.

[Matty]

I ended up just using some male spades into the original grey relay connector using the red,white, yellow wires, and because I was lazy I took a switched live signal from the radio. I ran these into a relay block, and fitted a standard 4 pin relay. Most are switched ground to the ecu.

It means the pump is always on, but it doesn't bother me. I started messing about using the starter motor exciter wire as a prime function to get the engine running, and hoped it would switch to the relay after starting, but for some reason the Rev counter signal wasn't good enough to switch the original relay after start up.

[Ian S]

I had a look at the article where I drew out the circuit diagram, but the photo is missing.

Found this from Scoff it's it's any use:

Here is the fuel pump pin numbers and wiring for the R5 GTT fuel pump:

pin 1: fat white = to fuel pump
pin 2: black = earth
pin 3: brown = tach input from AEI
pin 4: not connected
pin 5: yellow = ignition live
pin 6: fat red = battery live


Data taken from Ian Simpsons original article:

Fuel pump relay module wiring connections.

PIN 1: Live wire to fuel pump (This is the thick white wire on the white plug that goes to the fuel pump)
PIN 2: Earth (this can bolt straight to the body)
PIN 3: Rev Counter (This is the pink wire from the 3 pin plug on the AEI) Split the wire so that it connects to here, the AEI and into the car)
PIN 4: UNUSED
PIN 5: Ignition Live
PIN 6: Battery Live

[Matt Cole]

So im now running two pumps, one as a lift pump to my surge tank and a new high pressure pump to the rail. I've purchased new wiring and and new relay. My thoughts are that i leave the lift pump on the original wiring (triggered off the ecu and hacked into the appropriate wires on the original relay plug) and wire in the new relay and wiring to the new pump. This will also be triggered from the ecu, but i might just take new connections to appropriate wires, such as ignition live and battery etc.

Does that sound plausible?

[Ian S]

Do you want the safety of the pumps being stoped if the engine stops?

If so, then have the original fuel pump electrical module operate them both.

[Matt Cole]

Do you want the safety of the pumps being stoped if the engine stops?

If so, then have the original fuel pump electrical module operate them both.
Thanks Ian. The Adaptronic takes care of that as it only triggers the pump on prime and then when the engine is turning, sensed via the tdc sensor.

[Ian S]

Have the Adaptronic power them both?

[Matt Cole]

Ok. Update and all sorted!😁 I rewired both relays the same and used the ecu to trigger both. Everything up and running. Nearly finished the fuel system so will update once done.:agree: