Hi guys

There are a few different ways to do this, and you will end up with different results.

I'll start with the way I did it.

I'm fitting bike carbs so decided to buy a low pressure Facet Posi-Flow (details here http://www.fuelsystem.co.uk/web-facet.pdf) I decided on the low pressure one that pumps @1.5-4 PSI and if you are using a t-piece saves having to fit a regulator.

I wanted a system that would only pump fuel when the ignition was on and the engine was running, so here's how I wired it up.

I used a 30A 4 pin normally open relay like this

--quick note about relays--

A 4 pin relay is a type of switch. There's two circuits running through it. One circuit has a coil. When power runs trhough the coil, it energises and connects the other circuit.

--quick note about relays--

I wired constant live from the battery to pin 30 through a 5A fuse.

I wired pin 87 to the live input on the facet through an inertia switch like this

you can get them from eBay, most cars these days have them. It's a switch that will break the circuit in event of impact, you should attach this to the chassis. (I bolted mine to the bulkhead)

I connected pin 85 to switched live from the ignition switch (the big black wire) and pin 86 went through the oil pressure switch (low pressure, wire is blue+black, on the cylinder head) to ground. You'll need a new oil pressure switch that has dual circuits like the Wells PS121 (http://www.wellsve.com/) I bought this one from eBay. It means that it has the normally closed switch (like the VW one) and the two remaining pins are a normally open circuit which closes when there's oil pressure in the head.

With this setup it means it will only pump fuel when the ignition is on and the engine is running, and if I have an accident it will shut off.

I'll try to upload a circuit diagram in the next few days which may make it a little clearer.

With regards to mounting the pump, I mounted mine on the bulkhead next to the coolant expansion tank, and although in the instructions it says don't mount it any higher than 12 inches from the petrol tank height it works fine for me.

There are simpler ways to fit a facet. For example taking the live from the switched ignition (via a switch on the dash as well if you like so it doesn't drain your battery if you are listening to the radio with the engine off) however I wouldn't do it this way as if you have a crash you'll continue to pump fuel into the engine bay with a fire risk, and if nothing else you've got the hassle of turning the fuel pump on all the time.

Hope this helps, and this is a WIP so if you've got any suggestions please let me know.

Edited 16 July, 201115 yr by runforrestrun

great work iv been hopeing that a guide like this would be made.

got mine on a switch with an led in, and an led on the dash to say when its running, works pretty well also, if someone tries to steal your car they wont get far without the pump on!

You'll need a new oil pressure switch that has dual circuits like the Wells PS121 (http://www.wellsve.com/) I bought this one from eBay

Glad you got this all sorted.

Couldn't find an eBay supplier that ships the Wells PS121 to the UK though.

I only found this seller with 3 pins/dual circuits.

http://cgi.ebay.co.uk/390307233935

Probably wouldn't have had so much luck without your help so thank you very much indeed.

That's the one, I bought mine from a seller called 'holson' in the US.

is there an FAQ to do this on a mk3 does anyone know? :)

just replace the std pump with the facet one?

Great Info!

Did you ever get round to doing a circuit diagram?

Reviving an old thread.. I wired mine up with a relay and yet my facet pump died two miles down the road? Overheated as it was hot to the touch, let it cool down and it’s dead... doesn’t pump at all so i don’t get how my pump dead right out the gate? 

'Start new topic' is free if you've read other posts like this one.

 

Did you fit it high up in engine bay?

Most fuel pumps can't move air very well and are cooled a bit by petrol passing through.

Definitely not relay or fuse or connectors?