BMW E30 M20B25 Fuel Pump issues

[Arata 28]

Hi team. Arata here again with issues with my E30 (again haha).

Believe or not I'm having issues with fuel pump(s) failing relatively quickly.

From the previous owner to during my ownership, went through 4 pumps through last 3 years.

First one lasted 2 years+. That time around the fuel tank was rusty which I did not clean that time.

Second one lasted a week and died. Tested 12v directly and not even powering or moving at all.

3rd one and 4th one the pump was still somewhat working but not flow rate was down. (this time around the tank was taken out and cleaned thoroughly, no visual rust build up at this stage)

First and second one was from trade me (nz shop), the other two was Icon series.

 

Have already tested the fuel pressure regulator and is still working fine. Have replaced fuel filter frequent enough at the same time as fuel pumps, obviously with fuel filter facing right way of direction.

I will definitely consider checking the tank and give another cleaning but just wondering those who owns E30s out there that have replaced their fuel pumps, which brand you guys used? Will talk to the shop to see if they can swap with new one under warranty but if the brand is the issue then I would get either genuine one or high performance one.

Also wee question, what is the fuel pump check valve? Is this in-build inside the electric pump itself? Or is it the fuel breather? Some people suggested that put the check valve in the fuel line but not sure if that is ideal.

 

Any suggestions or ideas much appreciated.

Thanks team!

Arata the crazy Japanese guy

[e30ftw 396]

 

Check / Replace the wiring and connector going to the fuel pump on the cradle. I just had my walbro255 fail on me after barely 2000kms because the wiring in one connector terminal was loose. It must have been messing with the pump flicking it on/off while driving and eventually killed it. 

I replaced it with a deatschwerks 200. They're both two aftermarket options that will last and fit easily replacing factory pump and come with a a new connector pigtail.

 

[Arata 28]

8 hours ago, e30ftw said:

 

Check / Replace the wiring and connector going to the fuel pump on the cradle. I just had my walbro255 fail on me after barely 2000kms because the wiring in one connector terminal was loose. It must have been messing with the pump flicking it on/off while driving and eventually killed it. 

I replaced it with a deatschwerks 200. They're both two aftermarket options that will last and fit easily replacing factory pump and come with a a new connector pigtail.

 

Hey thanks for heads up. Yes the connector going to the fuel pump under the seat was repaired before so those are not moving freely anymore but I will double check. I’ll try get one from the supplier for the current one under warranty and hopefully it will last me enough till I get better one…

if I am getting the walbro255 fuel pump is there specific one listed for E30 set up or any of them is fine?

[e30ftw 396]

Nah the universal ones fit fine. 

Also the wiring I was talking about is on the pump cradle that goes into the tank itself. Check the wiring terminal that plugs into the pump for loose wiring and that the wires are soldered to the terminal properly.

[Jono51 58]

Hi Arata

 

you mention cleaning the tank.

 

Rust in the fuel tank perhaps?

if there is any rust you will need to address that issue firstly

[Arata 28]

2 hours ago, e30ftw said:

Nah the universal ones fit fine. 

Also the wiring I was talking about is on the pump cradle that goes into the tank itself. Check the wiring terminal that plugs into the pump for loose wiring and that the wires are soldered to the terminal properly.

Yep those are soldiered nicely. 

[Arata 28]

1 hour ago, Jono51 said:

Hi Arata

 

you mention cleaning the tank.

 

Rust in the fuel tank perhaps?

if there is any rust you will need to address that issue firstly

Yep have previously cleaned thoroughly and made sure it was cleaned dry after. But yes that could also be the case. I might have to get it cleaned again. 

[str8_6 270]

Rust will kill the pumps. Had two fail due to rust. New tank, new pump, no problems. 

[Arata 28]

5 hours ago, str8_6 said:

Rust will kill the pumps. Had two fail due to rust. New tank, new pump, no problems. 

Yep trying to save the tank by cleaning but I might have no choice but to get a new tank if it does not work. Where did you get your new tank from?

[Jono51 58]

Several variants of tank, I might have a used one ,depending on the type. otherwise new you'll either have genuine BMW $$$$ or aftermarket ,

 Some  aftermarket ones have minor issues , what I don't mention in this video is the filler neck requires some adjustment as it fouls on the subframe , however I suppose it is a cheaper option.