Will a late model M20 pump work for the M42?

[e30 Luv]

I had to replace my fuel pump so I bought a never-used pump from a member of M42club.



The one on the right is the pump I pulled from the car, the one on the left is the new one. The new one does not have the nipple for a return line. From searching around I think this pump I bought is for a late model 325 (not sure on i or e).
I was thinking I could either:

A) Switch the new pump over to the assembly from the old pump.
B) Jimmy-rig some kind of hose connection nipple for the new pump assembly.
C) Route the return line into the tank through another spot.
D) Sell the new pump and buy another new pump that's built for the M42.


So in order to decide what I'm going to do I need to know if the pump itself would work for the M42 since it was built for the M20. What do you think?

[gearheadE30]

You can actually get the inner main pump at NAPA for $50 or so. you will have to solder the wiring in but I think it is the same pump.

[devonjordan]

D

[e30 Luv]

D

eh?

You can actually get the inner main pump at NAPA for $50 or so. you will have to solder the wiring in but I think it is the same pump.

This is what I was considering but with the VDO unit I have sitting on my bench. I just wondered if anyone knew if the M20 pump was significantly different than the M42.

[EN318isPDX]

Just pull the guts out of the new one and put them in the old one

[e30 Luv]

D

OIC now. Thats what I'm going to do.

[DCColegrove]

Yes it will, but only the pump not the carrier...

I use them when we have a hopped up m42.

[e30 Luv]

I made it work. Went with option A to see how it would go, so far so good. I drove it around all day with no noticeable problems. I think I'm going to run some fuel pressure and flow rate tests to see what its running. Only concern right now is that the filter "sock" didn't fit on an snug as I'd like so I'm going to pull the assembly back out and grind the metal that's blocking it.

[ethirdy]

Just did this today :) Had to splice/solder wires, which made me nervous with fuel being involved, but it worked perfectly. m20 pump doesnt fit perfectly in the carrier, but it doesn't need to be perfect. It's in a tank full of fuel anyways ;)