Fuel tank repair

[hatepotholez]

Hi Guys,

So I have a small pin hole in my gas tank. The local radiator shop said they can fix it but they no longer coat the inside of the tank. They said they stopped due to the coating ruining the lines over the years. 

 

Any thoughts on this? 

 

Thanks!

[siteunseen]

You really don't have to coat the inside.  Blue didn't here and they weren't from the factory.  Just keep it full.

http://atlanticz.ca/zclub/techtips/fuel/gastank/index.htm

I used Red Kote on one 6 years ago and haven't had any problems so far.  And @Bonzi Lon used it some years ago and I don't think he's had any trouble either, hopefully he will reply and tell us the years. 

Maybe the radiator shop just don't want to fool with it?

[hatepotholez]

1 hour ago, siteunseen said:

You really don't have to coat the inside.  Blue didn't here and they weren't from the factory.  Just keep it full.

http://atlanticz.ca/zclub/techtips/fuel/gastank/index.htm

I used Red Kote on one 6 years ago and haven't had any problems so far.  And @Bonzi Lon used it some years ago and I don't think he's had any trouble either, hopefully he will reply and tell us the years. 

Maybe the radiator shop just don't want to fool with it?

 

The shop was referred to me by many and they also did my heater core for the Z. They do good work, but I am assuming they don't trust the coating for the gas tanks. 

Edited August 3, 2016 by hatepotholez

[Careless]

How do you guys plug the carburetor siphon line in the tank when doing the coating on the interior? The only tank I've ever done was an EFI tank for a different car, so it wasn't a problem.

But the carb line goes across the tank into the other side passed the slosh-plate. 

It's so tiny too, i'm afraid of plugging it with the tank sealer.

[siteunseen]

I put Gorilla Taped over the ends of all my tubes coming out of the tank.  After emptying the coating out I blew through them with around 90psi of air.  Waited 5 or 10 minutes and hit them again to be sure.  Worked good for me.

[Bonzi Lon]

Sorry for the delay in getting to this.

 

I did mine in a product called "Kreem", it took two of them, as these are made for large motorcycle tanks.  Like siteunseen  said above, a wire to make sure the vents are open and high pressure air to make sure they stay open.  A mirror on a stick and lots of light you can see for sure every inch of the interior. 

 

I have had no problems of any kind.  I did mine in the spring of 06 and did not use it until the refurbishment was done in spring of 08 before it saw fuel.  And that is the key to most of the failures that I have read about, not enough curing time.  So make sure it is really hard before you add gasoline. 

 

Bonzi Lon

[grannyknot]

On 8/3/2016 at 3:56 PM, hatepotholez said:

The shop was referred to me by many and they also did my heater core for the Z. They do good work, but I am assuming they don't trust the coating for the gas tanks. 

Some of the older formulations of tank sealer aren't fairing as well as the newer coatings with regards to the alcohol in fuel now, maybe they don't want to risk the liability and quit doing it altogether. Before I started using the POR15 tank sealant, which I love and have never had any problems with I would take the tank to bare metal with acid, neutralize it, dry it completely and then pour in some 2 stroke oil and coat all the inside surfaces, let it sit in there for a couple of days and then return it to duty. That's a fairly common procedure for restoring motorcycle tanks and works well.

[Zed Head]

Seems like the sealers are more designed to save tanks with potential pinholes, thin spots, cracks, etc.  If you have solid steel, the cleaning and rust removal is probably enough.

[siteunseen]

That's what I think as well. No coating is necessary for 20 years or so.

The red kote I use is was for diesel fuel mainly, off road diesel has a lot of ethanol.

 

[Careless]

I am considering the sealer because I had to use a dent puller to remove some of the dents on the tank, and in doing so- it turned out amazing and the tank looks almost new, but there are spots that did pull through and i had to patch up. so i'll probably be using the tank sealer from Caswell.

[jonathanrussell]

My theory (not supported by fact) is that these tanks were originally plated with cad or zinc or something else on the inside which helped preserve the tank. My low mile 72 240 tank looked really good on the inside with sort of a plated look in 90 pct of the areas I could see. When you acid dip the tank, boil it out, whatever....you remove whatever remains of this plating. Phosphoric acid will etch and preserve for a while but unless you keep the tank full all the time, I believe it will ultimately rust a lot faster than it did originally. So, I think coating is sort of necessary. I plan to redkote mine but make sure that I let it cure for a long time. I wish there was a way to re-plate it with something similar to what was originally used. There probably is a way but I just haven't found it. I could have it zinc coated but wonder whether it would hold up the way the original plating did. Again, I have no data / facts that support my belief that the tanks were originally plated. It is just my opinion.

[siteunseen]

Here's something about dipping tanks

http://www.metaldipping.com/fueltank_cleaning.php