Early 911 Fuel Tank Restoration

[kucharskimb]

This will be multi-part and I will update until I am finished and the tank is reinstalled.

Background:
The original tank in my 72 was cleaned and sealed sometime in the 90's with Redkote. However, the shop didn't do that great of a job, as most of the sealer pooled at the bottom and other places were bare.

My first thought was to scrap the old tank and purchase a reproduction tank. Upon arrival of the new tank, made by Tasker sheetmetal in LA, I examined the outside of the tank. The tank is supposed to be galvanized coated. There is galvanized coating (chemical reaction) and there is galvanized repair paint. This appeared to be the galvanized repair paint. Back to my original assumption that the tank would be made from galvanized steel, I quickly looked inside the tank. The inside is straight up sheetmetal. And as luck would have it, it was already rusty.





I sent the tank back for a refund and started exploring ways to restore my original tank. The guys at RedKote (Damon) were nice enough to explain how to get the old sealer out of the tank. Consequently, my restoration starts with multiple flushes and soaks of Acetone to clean out the old Redkote.

To do this, you must plug up all of the holes in the tank. I used rubber stoppers, plugs, old inner tubes with hose clamps, and even fabbed a plate to bolt onto the opening for the sending unit.





I used about 2.5 gallons of acetone, about 1 quart at a time to dissolve the old sealer.

I had fully anticipated using Redkote again, but the reviews for KBS Coatings was very good, so I opted with KBS.

http://www.damonq.com/TechSheets/Red-Kote.pdf
http://www.kbs-coatings.com/

(BTW, KBS also offers a POR-15 type coating called Rust Seal that is supposed to be superb)

I purchased the KBS fuel tank sealer kit directly from the company and it arrived via Ground shipping.
http://www.kbs-coatings.com/Auto-Fuel-Tank-Sealer-Kit_p_7-34.html

The kit includes a cleaner, rust remover/etcher, and the sealer.

The cleaner appeared to be a concentrated cleaner that you mix with equal parts water. After plugging up the fill hole in the tank, I tumbled and sloshed the tank to keep the cleaner moving around inside the tank. I did two applications of the cleaner, followed by a thorough rinsing out of the tank.

Note: The fuel tank is not really that heavy, but with anything bulky, you have to kinda man-handle it. The tumbling action requires you to have pretty good upper body and torso strength. Might be something to consider if you have limitations.

Next is the Rust Blast. The direction say to let it do its job for up to an hour or so for rusty metal. So, I've been flipping and sloshing the tank every 10-15 minutes to keep the inside surfaces wet with the solution.

Here are before, during and after pictures. Before still has the Redkote. During is immediately following Rust Blast. After is after washing out the Rust Blast.

Before


During
Note: The rust blast starts out the color of Windex. What poured out of the tank was black. Additionally, it left a crystalline coating that washed off.

[Carrerax]

Thanks for the report!!!! I need to also do this so Im anxiously waiting.....

[pwd72s]

Wow...a TON of work, Matt...hope it goes well. I'm sure many here thank you for the info on the repop tanks...

[kucharskimb]

These are pictures after the Rust Blast. I don't think the pictures really do it justice. There is still a fine layer of rust, but in many places it is bare metal. I suppose since the sealer is a POR type product, it isn't going to make too much difference...

The white is residue, which the product says is okay. It is zinc residue and acts as a binder.




I plan to seal the tank tonight. It has to cure for 4 days before fuel. While it is curing, I will finish the outside of the tank and prep the trunk pan.

Note: If I hadn't had to contend with the old Redkote, I probably would have taken the tank into a machine shop/radiator shop to have it cleaned out. Most radiator shops will also seal tanks for you. But I don't really think they are going to dedicate as much time to tumbling the tank and getting an even coat like I will...

[kucharskimb]

All right... The jury is still out. I have to let it cure, but it looks like I may have some bubbling from some areas that were too thick... If that is the case, it will have to be stripped again.

Race tank is starting to look pretty good...

[rrichar]

Matt,

I am curious what was the final outcome? I too am in Houston and am faced with a slightly rusty gas tank inside. The main difference I have to face is I have a CIS tank with the plastic baffles and therefore believe I am limited in my cleaning options.

An update would be appreciated.

[kucharskimb]

Sorry I never followed up on this. I was able to do some spot repairs to the couple bubbles. I had to order a small can of sealant, then use a small brush to apply it to the bad areas. I blame this on letting the sealant stay in the tank too long. I think 10-15 minutes would have been plenty, but I kept it in there for the max time of 30 minutes...

I finished the outside of the tank with Rustoleum Industrial Gray.

I have to say that I'm a little tentative about the sealant. At this point, I would have rather spent the money to have a radiator guy do it.

My 2 cents.

[Carrerax]

My tank has been sitting inside with gas in it for 25 years. I emptied it and have taken all the rubberized coating off of it and an going to have it done in SKS. Anyway, I was thinking about doing the chain thing with acetone and calling it done. Do you think this is enough or what should I use? I can take it to a radiator shop but I would rather do it myself if possible. Do I need to coat the inside? Thanks, Mark

[merbesfield]

Do you get the same results doing it yourself as you would from a professional tank restoration shop?