Fitting fuel pump to 316 carbed for engine swap

[JoshH]

Hey all.

In a bit of a pickle here! I have an 88 facelift with the m10 carbed engine in. I am about to begin an M52 swap so obviously need a fuel pump for an injection engine!

I bought a 63ltr tank inc fuel pump and senders etc.

I stumbled across a thread on the good old internet where a guy said

I had a 316 carb. I took the fuel pump and feed line from a 318i, it fitted straight in and then you just clip the fuel line into the clips along the floorpan (there is a space for it). Then I used my existing feed line as a return line from the engine.

The wiring was already there under the rear seat, but it's on the wrong side so you'll have to extend them which is easy enough.

Make sure you grab the car loom's plug for the pump with a bit of wire hanging off so you can join it into your loom (316 loom just has round terminals at the end, not the required multiplug). AFAIK that is it. The wires were purple and brown IIRC, but they should just be floating around under the rear seat on the passenger side.

It would be easier if you had the 316i, but far from impossible with a carb car

Having just pulled up the rear bench I can see no spare wires floating about under here




Could anyone help ? Thanks

[Grrrmachine]

Any pump wiring loom will be under the oval access panel (the driver's side one - your link says passenger because it's from a Yank website, presumably), so you may have to get your hands under there and reach around in the darkness.

[JoshH]

Any pump wiring loom will be under the oval access panel (the driver's side one - your link says passenger because it's from a Yank website, presumably), so you may have to get your hands under there and reach around in the darkness.

Ah ok, makes more sense. The way I'd read the quote was it'd be directly under the seat base not below the access holes. I will get a proper look when I empty the tank and drop it down!

[Brianmoooore]

The cable ties around the steel pipe in your second pic. are securing a plug and socket which joins the body loom to the loom you see going down through the floor pan.
The pump wires should be present on the body loom up to this socket.
You will probably need to add to or replace the loom that goes down through the pan.
The body loom for a car with a 63 litre tank is slightly different than that for one with a 55 litre tank, in that it has a branch for the LH level sensor, but this problem can be easily overcome by making up and running a loom across the top of the tank from the RH sensor to the left.