Author Topic: Removing old tank liner tips - Who's had success? Best Product?  (Read 4749 times)

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Offline davidru2

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In short, my CB550 tank has an old liner in it that's slowly coming off and clogging my petcock.

- Id rather not be using highly toxic chemicals if need be, as I've seen folks using acetone to Acids etc. 

- some using old screws and nails to help shake off the old liner, and some who don't. any big pro/con to either?

- I also don't want to ruin my nicely finished tank.

What sealer did you use?  Por-15 looks like they have a good set. Kreem?  Is a new liner even necessary?

If you've done this before with success I'd love to hear from you! 


Thanks in advance!

pics how inside of tank and what came out...
« Last Edit: April 01, 2018, 03:37:17 pm by davidru2 »

Offline calj737

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #1 on: March 31, 2018, 12:41:32 pm »
It all depends upon what the old liner brand is. If it’s Kreem (tan-ish, thin and flaky) then just about anything will remove that. If the old liner is an epoxy based (Caswell, POR or other) then you’re in for a bout with chemicals. Acetone will knock out some of them, but it takes a while. MEK works best, but it’s pretty caustic. I would NOT use an acid. That will attack the base metal indiscriminately. And you’ll end with a mess that’s worse than when you started.

Some have found radiator repair shops that can boil the liners out without damage to the paint. All depends upon your whereabouts. 
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Offline davidru2

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #2 on: March 31, 2018, 07:30:02 pm »
Thanks, this one seems more elasticity, but also tan in color.  Im going to pull out what I can and post on here.  I'm a year overdue to take on this task!

Offline ekpent

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #3 on: April 01, 2018, 06:30:47 am »
 Sounds kind of like Kreme. I had one fail on a Suzuki GT550 that I bought and was working on. The tank had sat dry for a very long time. I got lucky as I was able to grab it and eventually worked the whole thing out of the filler hole in one very dirty nasty piece. The saving grace was that the underside of it was all covered with rust and it had completely lost its adhesion. I removed a Kreme liner from an original 750 tank once using a very runny water soluble paint stripper called 1776 I used in my furniture business. Had the good good stuff in it they are trying to ban nowadays. It worked like a peach but was a very delicate operation to not get and spillage on the paint. Heavy coat of wax and keeping the exterior flooded with a garden hose is your friend here along with a tight seal on your openings. Be careful though as pressure will build up inside and you may get a surprise when you uncork the top  ;)
« Last Edit: April 03, 2018, 05:54:40 am by ekpent »

Offline davidru2

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #4 on: April 01, 2018, 03:34:02 pm »
Here's some pics from the tank and what came out...


Offline calj737

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #5 on: April 01, 2018, 07:22:26 pm »
Kreem. And not even Krispy Kreme!   :o
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Offline ekpent

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #6 on: April 01, 2018, 07:56:15 pm »
 Yep - and looks like it has rust on the backside also. Hungry for a doughnut now !!

Offline Little_Phil

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #7 on: April 02, 2018, 02:16:53 am »
David, I'll be following this closely as I have the exact problem on a 71 CB500K0. Immaculate with less than 5000 miles and a jade green tank with a disastrous Kreem liner. Was told that ethanol in fuel would attack it but I've had a bit of the liner sitting for months in our fuel which I think is 5% or 10% ethanol and hasn't touched it.
I was considering wrapping the tank in baking foil and aluminium tape to protect it.

Offline my name is nobody

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #8 on: April 02, 2018, 03:49:35 am »
My 550 tank did that after about 2 years with the por 15, which is normally a good treatment. My tank
had a nice repaint and I was bummed to say the least. As a last act of desperation, I filled tank with
the strongest concentration of vinegar available and left it sit for a week, periodically checking the progress.
I got lucky beyond belief, as I was able to pull the entire liner out as one whole skin. Not sayin others will
be that lucky, but vinegar does work, and is safer on the paint, just watch it and rinse if and when necessary.

Offline calj737

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #9 on: April 02, 2018, 04:12:41 am »
Not sayin others will be that lucky, but vinegar does work, and is safer on the paint, just watch it and rinse if and when necessary.
But vinegar is an acid and will eat the tank metal indiscriminately. You were very lucky.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Yamahawk

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #10 on: April 02, 2018, 04:15:30 am »
David, I'll be following this closely as I have the exact problem on a 71 CB500K0. Immaculate with less than 5000 miles and a jade green tank with a disastrous Kreem liner. Was told that ethanol in fuel would attack it but I've had a bit of the liner sitting for months in our fuel which I think is 5% or 10% ethanol and hasn't touched it.
I was considering wrapping the tank in baking foil and aluminium tape to protect it.
Phil, do you have E85 available for those Flex Fuel vehicles? It's a bit higher in ethanol... 85%!
Charlie
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Offline Stev-o

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #11 on: April 02, 2018, 07:29:25 am »

I was considering wrapping the tank in baking foil and aluminium tape to protect it.

Wrap it first with a couple layers of saran wrap then the foil...
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Offline Little_Phil

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #12 on: April 03, 2018, 02:46:42 am »
First sorry David for hijacking your thread, but we're both after the same result.
Phil, do you have E85 available for those Flex Fuel vehicles? It's a bit higher in ethanol... 85%!
Charlie
Charlie, don't think E85 readily available here. Ethanol is ethyl alcohol right so I could buy some pure. Or will anything else do it that is not too aggressive to paint...Isopropyl alcohol??...


I was considering wrapping the tank in baking foil and aluminium tape to protect it.

Wrap it first with a couple layers of saran wrap then the foil...

Cling film in the UK. But get the point thanks.
Phil

Offline PeWe

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #13 on: April 03, 2018, 03:15:13 am »
Good paint stripper. Look for methylene chloride on the label. Shipping name: Dichloromethane
It removes 2K. Just paint it as gel on the paint and wait. Inside a tank as liquid I guess.

I was lucky to find a seller that could send 5L to me last year. It was close that the forwarding company did not have any shipper due to the hazardeous and harmful content. It is banned in Europe, only for professional use.

Typica,all good stuff will be forbidden. Maybe they will soon allow Vodka to professionals only (alcoholics)? Some professionals are not allowed either... ;)
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Offline lowriderbud

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #14 on: April 03, 2018, 06:51:04 am »
I have a '78 750F and some PO had lined the tank with some kind of "red" epoxy material.  It was turning the gas red which was also confusing, but now makes sense - the ethanol was attacking the liner.  Another issue was the liner had been put over rust, so I not only had to remove the liner, but than treat the rust.  WARNING - never use a tank sealer to cover up rust. If there is a good part to my story, the outside was in need of repainting, so I didn't need to worry about being careful with the existing paint.

I read everything I could find on the internet and decided on acetone.  It worked, but took multiple applications and 2 gallons of acetone at $20 a gallon, and then I had to find a place to discard it when I was finished (and that is not part of my story). 

I treated the rust with baking soda, water and battery charger.  Again, this process took two applications, and the tank still doesn't meet my expectations.  I've used this process on a number (more than 3) of motorcycle gas tanks and they all came out like new metal inside. 

I'm running this tank on the bike (but the bike is still being restored and not on the road yet).  I'm also fighting carburetor issues and believe they are related to the condition of the tank before being cleaned.

Hope this is helpful.

Later, Bud...

Offline Stev-o

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #15 on: April 03, 2018, 07:16:50 am »
I have a '78 750F and some PO had lined the tank with some kind of "red" epoxy material. 



Most likely Redkote...
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Offline carnivorous chicken

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #16 on: April 03, 2018, 07:33:38 am »
Old liner sounds like Kreem -- don't use it to reline that tank. I remove it using acetone.

To reline, I've had succcess with Redkote and POR 15 -- but you need to follow the directions to the letter. POR 15 is a 3-step process, Redkote is a 2 step process, and Redkote can be thinned with acetone which can make it easier to use if you use acetone to line your tank. I've never used Caswell, but others like it.

When cleaning out your tank, wrapping it in something is one way to go, but can also lead to disappointment when you realize much too late (since it was wrapped and you didn't see it) that something got under your wrap and ate your paint. I've done  both -- wrapped a tank and done it without wrapping it and being careful, and I do the latter now every time. Something spills or sloshes, you can wash it off right away. Good luck!

Offline ekpent

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #17 on: April 03, 2018, 07:35:30 am »
 Yes the Redkote can/will turn the gas red. The instructions will indicate that as ethanol can leach out the color. I have noticed it but did not seem to affect how it ran. It supposedly according to them does not affect the liner and I have one where the red is now completely gone but liner intact.  http://damonq.com/techsheets/red-kote.pdf
« Last Edit: April 03, 2018, 07:38:55 am by ekpent »

Offline rupaulpierce

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #18 on: April 03, 2018, 07:45:53 am »
I read radiator shops could strip the whole thing in an acid bath... but apparently that's illegal now in Massachusetts. I've also heard you can bake the liner and paint off in a hot oven, but I haven't found a shop that seems to know what I'm talking about.

Offline greenjeans

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Re: Removing old tank liner tips - Who's had success? Best Product?
« Reply #19 on: April 03, 2018, 10:47:58 am »
Try boiling a big pot of water and pouring it in the tank.   If it's a Kreme liner, it will soften it and you may be able to pull it out all together.   Then, if it's just rust leftover, I'd just put some muriatic acid in there until the rust is gone.   Rinse well.  Phosphoric acid (driveway prep & etch) will leave it with some sort of protection from flash rusting.

If it does not leak, I would not put a liner back in there.

I am fighting an epoxy liner at the moment.  Muriatic acid did not work, nor did acetone.  Now I'm onto paint stripper.

I also wax the holy beejeeeebus out of the tank before starting anything.
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