shades of gray! Gas tank finish

[EARLY911ZOO]

It all looks to me to be a gray rubbery coating, anyone know the maker or a good substitute? does one need to remove the existing or can I coat over the old one? some areas are lifting around the sender, overall still ok.
is there gas tank porn also?
thanks

[911TES]

Hi Richard.

Yes, there is lots of good gas tank info. I just competed a complete tank restoration for my '69T. I plan to publish it here soon. I used a compiltation of the many excellent recommendations here.

Here a few pictures:

[911TES]

Final pic...

Most of my work was focued on restoration of the interior of the tank.

I'll gladly expand upon the post if anyone is interested.

Regards,

Bill

[EARLY911ZOO]

nice work Bill, whats the stuff in the larger bottle ...ends in pho?
could you detail the process? does the gun use a bottle or screw in the SKS?

[67softieS]

I am getting ready to restore 2 gas tanks. I would love to see more.

[orange911]

nice work Bill, whats the stuff in the larger bottle ...ends in pho?
could you detail the process? does the gun use a bottle or screw in the SKS?

OSPHO by Skyco. It's a phosphoric acid solution found at auto paint supply shops for about $20/ qt. It treats the metal and passivates it and there is a conversion of iron oxide to iron???. I used it after a battery failure and the rust was treated with this to make it ready for primer. I will venture to say that it is the best I have used.

[VintageExcellen]

How ya doing Richard....


FYI everyone - This should help save a little time in removing undercoat. When stripping Wurth SKS know that the material is PVC based. You will need a stripper that is a solvent to PVC, many strippers are not. I found a stripper at a hardware store (Home Depot) sold under the name: "Citristrip". This Gel stripper works well on all gas tank and undercoating areas, much better than a conventional paint stripper. You will need multiple coats in between scraping and wire brushing.

I used the orange stripper in conjunction with a large Milwaukee angle grinder with a heavy duty wire brush attachment to remove the loosened up old SKS. You will need a large amount of power and a large wire brush attachment (a twisted wire brush works very well too) otherwise it will take a significant amount of time to scrape off the old coating. Anyway you look at it restoring a 911/912 fuel tank is a hard job but necessary.

CAREFUL IF YOU HAVE A 1973.5 CIS CAR WITH A 1/2 YEAR ONLY RARE FUEL TANK. These tanks are only for the 2.4L CIS system and should not be mixed with tanks from other cars.

I have an extra restored short wheel base tank available if anyone wants to skip the restoration hassle and buy one outright.