Upgrading older fuel hanger?

[AndronPrime]

Hey guys I've been searching for information about my fuel tanks and the fuel sending unit for it (BMW Part #16121121500) When I searched the forums I didn't find anything. Same with google. My car is a 1978 E21. My sending unit is in the driver side tank and my hanger for my fuel pump is on the passenger side. I was thinking, is it possible for me to upgrade to the later hanger with my older tank? From looking at the diagrams I would have to upgrade the tank. My sending unit was working when I last drove the car so I am not too worried but I do wanna make sure if I need to, I can replace the unit.

Here are the two different set ups from RealOEM.com

Pre 1979

BMWE21Pre78.png

Post 1979
BMWE21Post78.png

[captain awesome]

I haven't had both of them in my hands before, but I THINK they have the same opening and locking style. So you might be able to put a late model assembly in the passenger tank, and cap off the driver side. E30 assemblies will fit the late models as well, but between the years there are different types. The 318is is probably the best suited if you are wanting to switch to only an in tank pump. The e30 sending unit is a bit taller though, so I think you'll still need an e21 version to get the fuel level right.

[AndronPrime]

That’s good to hear. If I see one pop up in my local pick n pull I’ll grab it to test fit. I’ll knowing the e30 ones will fit makes it a bit easier as I know there is one locally I can likely harvest from. Then I will have a sure answer! Thanks Captain!

[AndronPrime]

I haven't had both of them in my hands before, but I THINK they have the same opening and locking style. So you might be able to put a late model assembly in the passenger tank, and cap off the driver side. E30 assemblies will fit the late models as well, but between the years there are different types. The 318is is probably the best suited if you are wanting to switch to only an in tank pump. The e30 sending unit is a bit taller though, so I think you'll still need an e21 version to get the fuel level right.

Incase anyone else is interest. I picked up an e30 hangar at my local pick n pull. It did lock in my early model fuel tank. The hanger and pump is too long though. I removed the filter from the bottom of my pump for mock up purposes and it fit right in. I’ll have to make some adjustments when I get the upgraded pump but this should be perfect for my purposes. I’ll have to check my sending units again because the one from the e30 did seem to be about the same height. Unfortunately I’m at work and don’t have the pictures in my phone.