Fuel Tank Replacement

[SlamedIAm]

My current 20+ year old tank has completely rusted through on the fill pipe. It's dumping rust into my fuel and fudging everything up so I'm going to go ahead and replace it. I already have to drop the driveshaft for a guibo/CSB/trans output flange so now is the best time.

I've read up on the little bit of information available in preparation to do this. My main question right now involves the aftermarket tank I will be installing.

This is the tank I will be using:

http://www.ebay.com/itm/SPECTRA-PREMIUM-BM1B-Fuel-Tank-/230709709116?_trksid=p5197.m7&_trkparms=algo%3DLVI%26itu%3DUCI%26otn%3D2%26po%3DLVI%26ps%3D63%26clkid%3D5170978965406858282

The tank doesn't seem to be painted or coated in any way. Is there any reason I shouldn't just plug the holes and spray it with a truck liner or some sort of rubberized spray, or even just black paint? If this isn't a terrible idea does anyone have a suggestion on what to use?

The other question I have involves the fuel hoses. I went ahead and ordered the bent hoses for the fuel filter, the return line from the filler to tank (braided looking one), and the filler neck hose all from pelican. Are there any other specialty hoses I'm missing? In addition to this what size fuel line will I need to take care of the rest while I'm at it? I'd like to take care of all the soft lines while I'm doing this job. I would have done the hard lines as well but time and money are constraints right now after everything else and I'm not comfortable bending them myself.

Thanks guys.

[jlevie]

Is your car an 88 or later 325i/is/ix/ic? The tank shown is for those cars. It is possible to use that tank on an early car, but it won't be a direct fit.

In addition to the special hoses, you will also need 5/16" hose rated for fuel injection. You can save some money by using plain 5/16" fuel hose for the lo pressure lines. About 6' of each will be plenty.

[SlamedIAm]

Just the guy I was hoping to hear from!

The car is a 1990 325is. That definitely should have been in my first post.

For clarification you're saying I will need both 6' of high pressure fuel line and then an additional 6' of either more high pressure line or low pressure? 12' total?

[M-technik-3]

Then it's a direct bolt up, the one issue I have is the M3 always used an early tank.

[jlevie]

Just the guy I was hoping to hear from!

The car is a 1990 325is. That definitely should have been in my first post.

For clarification you're saying I will need both 6' of high pressure fuel line and then an additional 6' of either more high pressure line or low pressure? 12' total?

You can probably get by with a bit less but that is what I get to make sure I don't run short. There is at least three feet of each in the engine bay and other places where you will need it.

[SlamedIAm]

Sounds good. Any thoughts on coating the exterior of the tank? I figured some sort of rubberized spray might help protect the exterior of the tank.

[jlevie]

I think I'd use a brush on truck bed liner. Two or three coats should make it resistant to scrapes and rust.

[SlamedIAm]

What's the best tool for cutting fuel line? Box cutter?

[jlevie]

A box cutter works just fine.

[Simon S]

If I had any advice - it would be to go ahead and replace all the hard lines (including the rear/main brake line) while you're at it.

I can appreciate that you're strapped - but if the fuel tank needs replacing - then it's a safe-ass bet that the hard lines need/will need replacing too..

Mainly - I'd hate to see you go through all the work of dropping the tank - just to go through all that work again in a few months.

Trust me - this is not a job you'll want to do twice..

Coating the tank is one of those ideas where it shouldn't hurt anything - and be [somewhat] worthwhile.

This link provides a bunch of pictures I took during the process..

Good luck!

[SlamedIAm]

Thanks for the advice guys. Due to an awful hangover I lost yesterday as a work day and will be dropping/replacing the tank today while I'm replacing the output flange.

I wish I had gone ahead and gotten all of the hardline/tools necessary but at this point it's too late. I'm attempting to be back on the road by tomorrow afternoon/evening.

I probably will be doing this all over again this summer so that I can get all the hard brake/fuel lines but for now they're just going to have to tough it out.

Simon, your thread you linked to is amazing. Reading that over the past few weeks is probably what gave me the confidence to take on this project. Your car truly is an inspiration.

[Simon S]

Awesome.

Hope things go smoothly..

[Mr.SWISS]

Well project 87 325 (eta) has came into the garage now that the 24v is out.

This car has sat at least 5 years and the tank is nasty. I replaced the in tank with a 255lph pump and it isn't blowing through the inline like some posts said it would, others have said pull the inline and run a piece of hose and it will be fine. What to do what to do...

[SlamedIAm]

The actual swap went relatively smoothly. There was some swearing involved and I pinched my finger a little bit as we worked it back in but for the most part it wasn't very difficult. The hardest part was remembering which hose went where but luckily there are plenty of pictures available that made it easy enough.

The only real bummer was that I was unable to replace the braided vent hose. The passage it goes through was so corroded and packed full of mud I couldn't get it to budge and was afraid that even if I did I'd never get the new one fed through. The other issue is that my fuel pump chose to take a dump. Luckily it got me from Annapolis MD to Savannah Georgia without any issues and waited until the next morning to act up.

I'll be going with the Walbro 255lph in a few days here and hopefully I'll never have a fuel related issue again.

[Mr.SWISS]

Update on the eta, eliminated inline pump, installed generic 255 pump from fuelpumps.com in place of intank, and connected hoses with a brass reducer fitting, works great!!