Electric fuel pump problem

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VILLEocity

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I recently purchased a 1972 3.0CSi. It runs well but the fuel pump is leaking. I tried to replace it with an aftermarket unit but the car would not run for more than a few seconds even though it seemed to put out quite a bit of fuel at the end of the line.

I borrowed a fuel pressure gauge but it wouldn't give any reading for either pump. Either it's defective or I am:lol:.

To double check, I reinstalled the original pump and it runs fine so nothing else happened along the way to make the car not run with the new pump.

If anyone knows of any aftermarket pumps that definitely work for this car or good sources for oem new or used ones, or if you have an explanation for why the new one won't work I'd really appreciate it.

Thanks!

Rich
 
There are gobs of info on the subject matter of fuel pumps, replacement pumps, relays and testing. You just have to look a little. Here are examples:

http://www.e9coupe.com/forum/showthread.php?t=15626
http://www.e9coupe.com/forum/showthread.php?t=12495
http://www.e9coupe.com/forum/showthread.php?t=11111

It is possible that your original pump may be repairable. No idea about your replacement pump - without more information concerning its type and specific installation. Same with how and where you are installing a pressure gauge.


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HTH

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Both the CSi and 2002Tii run the same pump. They can be purchased as rebuilt units but are fairly expensive. Max lists them at $612.42 and the expansion tank at $118.69 so for total $731.11. The E28 fuel pump is $322.14. It pumps the same as the original, but the inlet and outputs are on the oposite sides that the original, the wiring needs to be modified for the different connectors so it's not just "plug 'n' play".

I replaced my CSi pump with one for an E28 on both my CSi, Athena and 2002Tii, Vern. Well actually one of my trusted mechanics did the swaps.
 
Rich, I replaced mine with a Bosch 69412, $135 from Autohaus AZ. The diameter is smaller. I made up the difference with a rubber strip. From your description, I also would replace the fuel filter which is downstream of the pump. I had a similar issue when I took possession of my CSi. Found a clogged inlet screen on the original fuel pump and a fuel filter loaded with sediments. Cheers, from Norwalk CT
 
The replacement pump is $386 at Penske, used in all late 70s and 80s BMWs, some mods may be required. Maximilian is way over priced on everything unfortunately.
 
I just replaced the pump on the 3.3li with one from an e28. Andrew is correct about the inlets being on the opposite side. I just made two jumper wires with eyelet and spade connectors since the e28 pump uses two post terminals.
 
Wow so many options.

Does a tank of gas last longer if I swap the inlets at the fuel pump?

Anyway the pattern seems to be that the newer the car the shorter the fuel pump life.

And that the electric pumps last less than the mechanical pumps.

And that any topic is good for a rant today. I hear myself sounding like the 'The rent is too damn high presidential candidate.
 
adawil2002 said:
Both the CSi and 2002Tii run the same pump. They can be purchased as rebuilt units but are fairly expensive. Max lists them at $612.42 and the expansion tank at $118.69 so for total $731.11. The E28 fuel pump is $322.14. It pumps the same as the original, but the inlet and outputs are on the oposite sides that the original, the wiring needs to be modified for the different connectors so it's not just "plug 'n' play".

I replaced my CSi pump with one for an E28 on both my CSi, Athena and 2002Tii, Vern. Well actually one of my trusted mechanics did the swaps.
Click to expand...


What did you do for a mounting bracket for the e28 pump (and filter too)?


Saw this on an E3 on the internet:
 
adawil2002 said:
Canister filter before the pump as it doesn't have an inlet screen. Pump fits in the bracket with the expansion tank, it's the same diameter as the original pump.
Click to expand...

Excuse my ignorance but this black thing is not another filter but an expansion tank? So reuse that?
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It's a reservoir or sump for fuel. Needed on cars without lifting pumps in the tank.
 
Thanks a bunch. I'll put another filter before the pump, but hard to find a filter using 7/16" inlet/outlets
 
Hi Rob,

I have the fuel pump from my CSI if you are interested. I haven’t tested it but I can wite my DC box to test.
 
Well tea head - is that trunk picture from the museum of automobile bombs? Something they found in Iraq being driven by a suicide bomber?
 
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adawil2002 said:
Canister filter before the pump as it doesn't have an inlet screen. Pump fits in the bracket with the expansion tank, it's the same diameter as the original pump.
Click to expand...

The e28 in line pump is smaller in diameter then the original pump and the bracket will not work. You can order a bracket for an e12 inline pump which fits right in to the mounting tabs under the car. The bracket is identical with 2 exceptions-
1.the e28 pump fits
2. The bracket also has a fitting for a fuel filter.

You will need to make a jumper from your plug to the newer e28 pump.

Part #16121120970

#3 on the diagram

https://www.realoem.com/bmw/enUS/showparts?id=4701-EUR-05-1980-E12-BMW-535i&diagId=16_0159


 
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