Been working on my 81 FI Spider. It sat for 10 years because of a transmission problem. Now the tranny is good, but the fuel tank is not. I was wondering if anyone has relined their tank? I am familiar with the procedure, I relined an old motorcycle tank before, but never a larger tank. Any thoughts, pointers or other options would be much appreciated!

Also, how advisable is it to replace the fuel lines...there are no leaks, they're just a little stiff, and have had the same gas in them for about 10 years. Should I wait till after my tank and injectors are clean and filter replaced and see how it runs or just replace them?

Just not sure how big a job it is.

I had my fuel tank redone using the "Renu" process. Google it. They drill holes in each section of the tank (between the baffles) and sandblast from the inside, then coat it with an epoxy-type system. Lifetime warranty for whatever that is worth. It was recommended to me by someone on the Mira site who had it done and felt it was a better result than the after-market tanks (which he had first bought and had rusted). About the same cost as an after-market tank as I recall.

I replaced all the hoses to the tank while I had it out.

A couple of options I'd offer... anyone nearby parting a FI car out? see what that tank would be like.
I've used a 3 part system probably similar to what you used on your bike. I first stuffed a small link chain or pebbles in there with a little water and shook the tank around for awhile (make sure no one is watching that step if you can't dance or have "man breasts"). A bunch of crud came out and then a solvent cleaner, shake some more, some real smelly prep(smelled like acetone) and then some kind of sealent and shake/roll the tank around some more. So far has worked great,no issues with the FI pump or filter.
Chris

Eastwood makes a kit, I used it on our Farmall Tractor and it seemed to work OK. Just need to make sure you follow the directions and that everything gets coated with the sealer, or the rust will come back due to the condensation in the tanks when not full of gas.

Definitely replace the rubber lines, and use good quality hose clamps. Do this once, and you'll never need to do it again.

The Spider fuel tank has many baffles, so the "length of chain trick" won't completely clean it. For DIY, I'd suggest the Eastwood, POR-15 or other kits. "Get your Freak On!" and shake that thang good now. Caution: the tank must be completely dry between steps. Use a small fan over the sender opening. Most radiator shops also provide this service for nearly the same cost (plus a guarantee), but you lose the entertainment value of DIY

The tank on my `77 started to 'weep.' This surprised me because it seemed physically sound. The reason for it - and the restoration shop that does my work says this is not uncommon - is corrosion where the two halves of the tank come together. (He had a BMW gas tank in the shop awaiting disposal that had been replaced for the same reason so he was able to show me what he meant.) The metal there becomes porous and at least in the beginning doesn't leak in the form-a-puddle sense, but the bottom of the tank is always damp with fuel and the smell of gasoline is always present. Eventually it will worsen and become an actual dripping leak.

In his judgment, apart from where a car is rare and a replacement unavailable (or extremely expensive), replacement is the better option.

I bought a replacement for mine during IAP's big sale for about $200. It'll go in first thing in the Spring.

-Don

I just posted a question asking for advice on fuel tank lining! Sorry everybody and in future I'll check the list of topics before posting a stupid question.

Charles

Just to follow up, I went with a Kreem liner, for 40 bucks I got a pint of liner, a rust dissolving solution and a prep solution. I believe muriatic acid works just as well as a rust dissolver/etcher and acetone works to get rid of water to prep for the liner. I had good results, but it does take some time and effort to ensure all the rust comes out especially with all the baffles.