TOPIC:

The fuel tank came out really nice. It was covered with rust inside and looked hopeless. That has changed and it's like new now, sealed for eternity. The process was a long one, but the final results leave no regrets.

There were many steps, many repetitions. Here's how it went.

The initial rust removal was done with regular straight white vinegar and 2 pounds of nails. Rinsing with water (shower head hose in a bathtub) and baking soda to neutralize the acidic environment.

It's unbelievable how soon and fast the tank covers with rust after removing the vinegar and rinsing it! It's called flash rust and very superficial. But if left alone too long, it grows and the tank has to be cleaned again. It's all surface then, so a much easier task.



After the initial cheap cleaning with vinegar, I used POR-15 cleaning solution. I had to use the nails again because some of the flash rust build up didn't come off in all places (I left the tank sit for a couple weeks after the vinegar treatment). With some shaking, the inside turned out spotlessly clean and rust free.

Next step was POR-15 metal prep solution. It etches the surface and introduces some Zinc.
The tank has to be completely dry after this - I used a hair dryer and took my time.

Clean but some minute flash rust just minutes after drying the tank.





After prep solution treatment before rinsing.





The last - POR-15 tank sealant. Poured it in, sealed with duct tape, move around to make sure the compound seals everything inside. Drained and let it sit to dry. It's quite a stink at first, I had to move it around but most of the time it stayed locked in the bathroom. The smell goes gradually away, and you can't smell it after five days.

The tank is sealed and ready for gasoline. It just needs a paint job, and that it will get. POR-15 sealant is extremely durable. You can't remove it. I am very happy with it and if I need to treat another tank, that's what I will use. They should pay me for my endorsement, hahaha

Good progress, and thanks for the detailed write-up. All this information will be so helpful if I ever start on my restoration project.

Few pictures of the sealed inside gas tank. It's a thin but very durable layer, hugging every corner and imperfection. POR-15 instructions say that it can be poured over any flash rust and will seal pinholes and any small leaks, and whatever rust is left (which is neutralized after the treatment). But I decided to have the tank completely stripped from any rust. That's the way to go in my opinion. First use vinegar, as it is cheap, then the POR-15 solutions to finish the job properly.

Nice work on the tank reline!

My experience is that you don't need anything else other than the POR rust stripper (which I believe is simply phosphoric acid which can be bought in bulk at a pool supply store). I used it on a very heavily rusted tank and it got rid of all the rust without the use of anything else. Lots of people have had success re-using the recovered POR stripper on additional tanks.

As far as the liner goes, I did my 900 tank in about 2000 and it's had gas in it ever since. After 18 years of use, I think it's pretty durable but maybe it takes a while to break down

Hi Stan,
I have enjoyed your story of the rebuild. I would like to participate and support in a small way too. Send me a private message with your postal address and I will mail you a brand new Boot for your swing arm. It will be free of charge to you.
Best regs, Lauri

www.kawasaki1300parts.com

Thank you Lauri! That's really generous of you. I will send you a PM today. There will be many more fun posts when I will be putting the bike together.

Bucko:
I wonder if POR has another rust stripper, maybe that's what you were using? The stripping solution supplied with the motorcycle tank kit I got was definitely not just acid. It was quite soapy, lots of suds. It had degreasing properties, and also most likely something else to remove any old coating. My tank had quite heavy rust (20 years or more sitting unprotected?), and I am 100% sure a short time soaking in any rust removing solution wouldn't work. It was a long process, that's why I decided to use vinegar: it's cheap and easy available in large quantities. So I added this step of prep work using it. Using vinegar and POR-15 was suggested to me by a few bike pros. It would not be possible to shake the tank with nails inside using the supplied POR solution with the amount of suds it was generating! Like a bubble bath pretty much. Vinegar doesn't bubble.

As to just rust removal, I researched this and also watched videos comparing a variety of rust removing medium. Metal Rescue was always coming on top, but it's too expensive for me for such big jobs. Vinegar worked marvelous, then POR finished the job.

The POR-15 etching solution is reusable.

One last advise for anyone using POR-15 tank coating - use rubber gloves! This stuff really sticks to your hands and can't be removed except for gradually over a period of a week. Don't ask me how I know it.