Fuel tank reline kit recommendations?

[bruce_launceston]

After draining the fuel and water and large flakes of old tank liner out of my fuel tank I have decided to reline it again.
I did it many years ago with I think 'Kreem'. I removed a lot of this before I had the tank resprayed 18 months ago. It had started flaking off badly.

Tonight I flushed the tank out with thinners 3 times. The thinners softened and removed most of the remaining tank liner. The last flush I added 50 chrome screws and gave them a good rattle around with the thinners (it took me about 20 minutes to shake them all out the fuel tap hole!).
The crap that came out after adding the thinners was disgusting, it looked like vomit!

Anyway my question is; I have found 3 products available in Australia and am after recommendations.
POR 15 (seems to be highly recommended and has been around for years.)
CASWELL gas tank sealer and
KBS Gold Standard Tank Sealer.

All these products are made in the USA and come in kits with a cleaner, a rust convertor/metal prep and the sealing coat and all seem to be priced about the same.

The Caswell product seems to be a two part final sealer while the POR 15 and the KBS kit have single part sealers.

Before ordering a kit I would like to hear from people that have used these products.

Cheers Bruce

[Bob_Roller]

I just got done doing this process on the '84 LS tank .

The inside of the tank looked like an old exhaust system off of a car, it was quite bad .

I purchased a POR 15 kit, the contents are a bottle of caustic solution (sodium hydroxide), bottle of phosphoric acid solution, a can of sealer/liner itself .

I had heard of a method of using molasses and water to remove the rust and liner from the tank .

I was up for a bit of 'myth busting', tried it, and it does work .

The molasses 'ferments' into a substance that contains acetic acid, the acid that vinegar contains .

Didn't quite get all of the rust and liner out .

I have access to concentrated citric acid at work, filled the tank with it, and in two days all of the rust and liner were gone .

Only problem I encountered, was a flash rusting when flushing the tank with hot water .

Got a gallon bottle of phosphoric acid, it removed the flash rusting, but a bit did come back after rinsing the tank with water again .

Poured the POR 15 liner into the tank, and got it coated, the hardest part to get properly covered, was the drain tube for the filler area .

If I were to do  it again, I would see if I could get the POR 15 liner material by itself, the caustic solution, and the phosphoric acid in the kit didn't do much in my case .

Then get some strong vinegar, I've seen as high as 15% acetic acid content available in retail outlets, but 5-10 % seems to be more the norm .

Let the vinegar sit in the tank for a few days, sloshing it around occasionally .

Flush the tank with hot water to remove the vinegar .

Pour the phosphoric acid in the tank, and do the same, slosh it around to remove anything else that may still be in the tank .

Flush the tank with hot water again after draining the phosphoric acid out .

Place the hose from a shop vacuum, on the outlet side, so it blows air into the tank for a few hours and dries it out .

Then pour the POR 15 liner material into the tank .

[Semper Gumby]

I've used the Tank Kreem in the past and it is still in a Honda 400 tank from about 10 years ago.  I have used the Bill Hirtch kit which looks like Tank Kreem.  Single part Epoxie.  I am going to try the Caswell kit here in a week or so on my R65 and the Montesa 247 Trials bike I have.  It is a two part kit and some of my Brit biker Gurus like it.  They say it's good with Alcohol fuels.

Goood luck!

[bruce_launceston]

My choice might come down to what is easier to get although I like the idea of a two part epoxy.

It does sound like it would be harder to apply, they say the epoxy and the tank need to be at the same narrow temperature range or the finish will be too thick if cold or be too thin and difficult to get to 'stick' in a thick enough coat if it is too warm.

I have found a number for a local distributor for POR 15 so I will start with that and see if they stock the tank sealer.

The Tank Kreem makes a awfull mess when it fails, my tank was previously full of large dry flakes after storage. The thinners seemed to soften and remove most of the remaining liner but its hard to see inside a R65 tank.

Despite all due care I will still have to repaint the flat black lower to my LS tank as the thinners has streaked it and removed some, luckily the PPG 2 pack yellow seems untouched by it.

[Bob_Roller]

I think the most important thing to accomplish, is to get all of the old liner out of the tank, as well as the flaky rust, so the liner has a good surface to bond to .

Just like painting, if the surface preparation isn't done correctly, the paint job probably won't be as well .

[Semper Gumby]

Bill Hirtch recommends the gel-like Aircraft paint remover to get the single part liners out like Tank Kreem.  One gallon can and swirl-it all around.

The Caswell Kit says right on the box:

"-2 Part Phenol Novolac Epoxy
 - Coats Two 5 Gal Tanks, or One 10 Gal
 - Withstands ethanol and racing fuels
 - No need to remove rust or corrosion
 - Repairs failed Kreem or Por-15 sealers
 - Fully cured in 24 hours"

"Permanently seal Steel, Aluminium, Fiberglass and Plastic Tanks"

In the instructions it says for steel tanks "place a hand full of drywall screws with about a pint of acetone or lacquer thinner into tank and shake them around vigorously for several minutes.  These will dislodge any loose particles of rust,... dispose of contaminated solution. Allow to dry."

I'll let you know how it goes but it may be a while.

Oh I forgot to mention the picture of the two cans of the kit are sitting next to a Maroon Harley Sportster tank.  This may put some people off...

 8-)

[Bob_Roller]

If you choose to put a solution into the tank, and let it sit for a few days, it would be best to have the tank 'vented' .

During the rust removal process, gases are given off, and if the tank is sealed with rubber stoppers, or something similar, one of them will be dislodged by the pressure build-up, of if you have a significant barometric pressure drop, the tank becomes 'pressurized', and almost without fail, the stopper holding the fluid in, will be the one that goes first .

[bruce_launceston]

Thanks for all the tips Bob and Bill, it would be a right pain if a bung got sucked into the tank when you were about to reline it.

I have a guy dropping of a POR-15 kit tomorrow so there is a job for sometime when I don't need the bike for 4 or more days.

I ended up putting it all back together on Sunday so that I could ride it to work this week, there are no spare cars about as we are waiting for a front wheel bearing for my sons van and he is using my other sons car in the meantime.
I figured there was no harm in refilling the tank with petrol as the kits come with cleaning and surface prep solutions. I also repainted the flat black lower where the thinners had damaged it and blew out all the fuel lines and fuel filter and main jets with the compressor.

[Darwin_R65]

Guys up here use the POR15 but have built a rotisserie for tanks to ensure it is even.