• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

  • Beginning April 1st, and running through April 30th, there is a new 2024 BMW MOA Election discussion area within The Club section of the forum. Within this forum area is also a sticky post that provides the ground rules for participating in the Election forum area. Also, the candidates statements are provided. Please read before joining the conversation, because the rules are very specific to maintain civility.

    The Election forum is here: Election Forum

Gas tank sealant removal

potman

New member
Help!
I'm restoring an R75/6. Whoever had it before me, coated the inside of the tank with some kind of sealant. It's flaking off and I'm trying to figure out how to remove it. I went onto YouTube, and all the videos said to use acetone so I tried it. The acetone made the sealant soft but didn't disolve it. Does anyone out there have any ideas?
 
Welcome aboard potman!

Acetone by itself won't "strip" the coating... throw in a hand full of drywall screws, nuts, etc. to help abrade the interior.

I used the "POR-15" relining "system" on my /5 tanks. The solvent used by them is based on methylene chloride ... nasty stuff, but it strips coatings really well.

Dad's brand paint stripper is basically the same stuff, only much thicker.

081037338311.jpg


A WARNING... Both of these products will DESTROY the paint finish on the outside of the tank.
 
Welcome to the forum! Snowbum has a page on this:

http://bmwmotorcycletech.info/fuelmiscl.htm

Basically, you're going to put into the tank an array of nuts and bolts followed by vigorous shaking, draining, repeating. Probably need to remove the petcocks and plug with some rubber stoppers. Certainly don't want the petcocks on when applying the new sealant.
 
Oh Man: I just went through this on the tank for my sons' 83 seca.
Pin hole leaks below the petcock line.
Very long story shortened:
Acetone softened the factory sealer and trapped the screws I had put in to loosen the crud.
Final solution was 2 gallons of MEK and a 3 day soak.
It WILL mess up the paint.
 
Welcome aboard potman!

Acetone by itself won't "strip" the coating... throw in a hand full of drywall screws, nuts, etc. to help abrade the interior.

I used the "POR-15" relining "system" on my /5 tanks. The solvent used by them is based on methylene chloride ... nasty stuff, but it strips coatings really well.

Dad's brand paint stripper is basically the same stuff, only much thicker.

081037338311.jpg


A WARNING... Both of these products will DESTROY the paint finish on the outside of the tank.

Thanks for the info Imo1131. The paint stripper is a great idea. Potman
 
I had a BMW friend who took a piece of glass and broke it up into tiny little pieces with "sharp" edges and then put in tank and shook up like those have suggested above. He claims it worked well.
 
My opinion is to use the larger proportions of "POR 15" that are suitable for automotive tanks.

The smaller kit that is sold for motocycle tanks have the right quantities for a motorcycle tank in a perfect world. Not this one.

Charlie
 
The smaller kit that is sold for motocycle tanks have the right quantities for a motorcycle tank in a perfect world. Not this one.

+1

I should have mentioned that. "Dad's" works well although it's a bit thick, dilute with acetone to desired consistency. And WEAR EYE PROTECTION AND GLOVES this stuff is will burn skin.
 
Back
Top