Fuel tank replacement; difference from 87 to 89?

#1

We’ve got to replace the fuel tank in the E30, and I’ve noticed that there are two types of parts, one for the earlier cars and one for the later cars. The earlier tanks have a smaller capacity (about 15 gal) versus nearly 17 gallons on the later ones. Are there any other major differences that anyone knows about? Would it be easy to install an earlier-spec tank in a later car?

#2

The pumps are different (2-pumps vs 1-pump setups), and by extension so is the plumbing and wiring. I think you had best stick with the tank style that matches your car unless you care to deal with the other differences.

#3

I’m pretty sure that if you search the archives, you will find that you cannot update the tank (should your car require the older style). Another option is to go with a fuel cell. The word on the streets is that the older style tanks suffer from fuel starvation on hard right hand turns. My experience corroborates that theory. I’ve changed pumps, filter, bla bla blah. Nothing, I still can’t run less than 9/16 of a tank or so.

#4

My experience is that the newer tanks have starvation issues as well.

However your mileage may vary. I replaced my tank (90 is)with a new one. Wasn’t that difficult to do while the rear subframe, etc. was out.

#5

My opinion is the newer tanks are safer, much less crap hanging under the car and less hoses to leak/split/get ripped off the car on an off course etc. It is much easier to change the single in tank pump than the early mess.

Al

#6

from what I understand the flange where the pick up is changes from the single to dual pumps (hole is smaller since they don’t have to fit the helper pump in there. Changing the tank is kinda a pain, once you get the drive shaft out if goes pretty easy (it also helps to unbolt the subframe and let it hang so you can get to some of the bolts easier that and snaking the rubber filler hose in and out is easier with the SF down). Just make sure you have all the rubber lines bought before hand so you can replace all those while you have it out.