Should I seal my gas tanks?

[Mike B]

I need some quick opinions about sealing my gas tanks. I had to replace a hose on my 72 240Z, so I pulled the tank this weekend. The exterior was ok, but needed a repaint after 40 years to look as good as the rest of the car. I had also already pulled the tank from HLS30-00210 since it had been sitting for 15 years and wanted to check it before restarting the car. It was in similar shape. I decided to paint the exterior of both with POR-15 products, which I did yesterday and they both look great now.

The interiors of the tanks looked excellent with just a few minor spots of very light surface rust. I have a can of POR-15 fuel tank sealer and thought I may as well treat the inside of the tanks since I have them out. I cleaned the tanks with Marine Clean and Metal Ready and dried them out over the past two days, so they are 100% dry now. Today will be the last day of warm weather for a week or so, and the sealer has an ideal temp of 72 degrees. If I am going to seal the tanks I need to do it today, or wait another week, since it will be cooler and raining off and on after today.

Should I go ahead and use the POR-15 sealer as a preventative measure since I already have it ready to go? If the tanks lasted almost 40 years they will probably last at least another 40 as is. The Metal Ready etches the tank and treated what little surface rust was there, but I have only used it as a prep for further POR-15 products. Would there be any problem using the tanks without sealing them now that they have been treated with Metal Ready? I have a couple of spare tanks from parts cars that I may try to sell at some point. They are not quite as clean as these were, so I could use the sealer and left over POR-15 to seal and coat them. Any opinions on this?

-Mike

[Diseazd]

Mike....If it's that clean, I wouldn't "futz with it". Put it back on as is and run it!

[geezer]

I see this differently. I would agree not to "futz with it", if the tanks had not been treated with the Metal Ready. Now that they have been treated, what is left is etched, very clean metal that will be more subseptible to rusting since any coating that was still protecting the surfaces from when they were new, have now been removed. I think you have to follow through with the sealer now, in order to protect the fresh surfaces.

Edited May 18, 2009 by geezer

[conedodger]

I used the POR15 tank sealer and it was not only very clean it was pristine... I would use it again.

[280~Master]

Mike,

Go ahead and POR the tank now while out. Don't risk it. Do it right the first time. You will fill better in the long run. Plus its well worth it.

[26th-Z]

I agree. Seal the tanks. The POR product is excellent for this.

[Mike B]

Thanks for the input guys. The tanks are sealed now. There was plenty of the sealant for both. Just have to wait for the rest of it to drain out now.

-Mike

[280~Master]

Mike,

I would give it 72 hours of dry time.

Maybe even longer if its raining.

John

[Mike B]

Just thought I would show some before and after pictures now that I have the tank back in my 72. I'm really happy with how it turned out and glad that I went ahead with sealing the tank while it was out. Here are some pictures of the tank and straps before I took it out and after the POR Metal Ready and Marine Clean treatments.

-Mike

[Mike B]

Here are the pictures after the POR-15, top coats, and sealant.

-Mike

[=Enigma=]

Funny, I just did the same thing while I had the tank out to replace all the evap hoses. The tank was in such good condition on the inside and out I almost didn't bother, but I figured I might was well do it while I had it out. I also took the time to replace the rubber on the straps with some better material. The pics of the process are here: Fuel & Evap System Refresh

[240dkw]

Mike: The tanks look great, I just finished media blasting the outside of my tank today and planned on POR for the outside. The inside looks new with no rust anywhere and I was going to leave it as is but after seeing what a great job the tank sealer does I think I will do the same.

Dan