Board logo

Avon wiring - fuel pumps
DaveFJ - 17/7/07 at 12:09 PM

I am trying to work out how best to wire in my fuel pumps to my Avon Loom...

Thing is I'm not the best at vehicle electrics so need a little guidance

here is the problem:

I have the standard Tiger 6 fuse loom which presents 2 wires (+&-) to the rear of the vehicle. To my knowledge this is not coming from a relay as there are only 2 relays on the loom - 1 for flashers and the other, I think, is lights...
Not sure on how thick these wires are and therefore thier capacity...

I have a Sierra standard EFi pump and a Facet red top pump acting as an LP pump to fill the swirl pot.

I also need to wire in a safety cut out 'bump' switch and the fuel pump output from the Megasquirt. (I think I also have an output from my alarm - but I need to confirm this....)

So... my question is this.. what is my best way of going about this? should i run a decent wire to the rear end and use the current wire to work a relay? or will the wire in the loom be up to the job of running both pumps(if you know your way round the Tiger loom)? If so should I run a wire from my MS to the relay via the cut off switch? And if my Alarm does have a fuel pump supply do I need to use a second relay?

Whilst i am on the subject, I was wondering where best to mount the relay? I had a feeling that it was probably not good to have it next to the pumps etc?

Clear as mud?

I know this may be better in the Electrical section but I wanted to get some info from the Tiger community....

Cheers


PeterW - 17/7/07 at 01:07 PM

Dave

From what I have seen of the Tiger loom, its up to running about 12a through the wiring to the back of the vehicle.

The wire in question runs directly from the 2nd (?) fuse, straight through to the plug at the back. They are pretty easy to trace, and you could chop the loom to drive relays etc. Its not a complex loom, just about 3ft too long

Cheers

Pete


DaveFJ - 17/7/07 at 02:09 PM

B*gger is, loom is now all nicely routed buttoned down and wrapped in convoluted tubing

It's gonna be a right bitch to get at under the dash

All my fault - I didn't think this through earlier

Any idea what sort of current I will be looking at for both these pumps?


DaveFJ - 18/7/07 at 09:45 AM

Measured the O/D of the wire in the loom last night. (I know it doesn't mean a lot because i reallyu need to measure the core but - hey it's all I have for the mo....)

anyway the wire is reasonably meaty @ 1/10" or 2.5mm

so do people reckon this might be up to the job of running both pumps?

thing is this wire is already in the loom and controlled by the ignition so would be good if it could be used and then just run a cable from the megasquirt via the bump switch to a relay so that the MS and/or bump switch can shut off the pumps as neccessary


Rudy - 18/7/07 at 09:56 AM

Yes I think you can do in that manner. And 2.5mm is ok