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Gas tank need to be repainted inside.

1der

New member
I have a 1990 R100RT that needs to be redone on the inside of the gas tank. Any recommendations?
 
I used red cote. Not sure of the exact spelling. I first stripped the original coating out using aircraft paint remover and a hand full of nails as the abrasive and a lot of shaking. Cleaned up the stripper with water. Rinsed with IPA and dried before using the red cote. I'm very pleased with the results.

Jim O'Coin
 
I have used POR15 with good results - it even closed up a couple of pinhole leaks. You have to take your time on prep, though, for best results - don't cut corners. I did mine while making a long slow smoky barbecue.
 
One very wise person suggested one time on how to do the cleaning out of the inside of the tank.

He took a glass window from a automobile and broke it into a thousand little pieces. These worked as the "abrasive" in the tank. He then shook it to get the glass to work. Someone (not sure if the same person) actually put glass bits inside, closed tank, wrapped it very well, and then put it into wife's dryer.

Not sure about the last part. But I heard that after his wife did up the next load of his clothes, he look like a pretty "sharp" dresser!!
 
Preparation Preparation Preparation

You can't beat doing it right the first time. Stay away from that Kreme stuff, it won't hold up to the new fuels. I did a /2 tank with Por 15 and I am not impressed with the results, I can find little spots of bubbling and softness upon inspection through the cap opening.

Re-Kote is bullet proof but will eat the paint off the tank if you are not careful. I did a /2 tank 13 years ago and it still looks like the day I put it on the bike. That tank had the dreaded knee pad holder leaks that Red-Kote sealed up nice and neat.

Clean the tank real good with water and some type of media, dry out with a hair dryer and than swish some MEK around inside before you apply the Red-Kote. Take your time and you will be very happy
 
Caswell Plating makes a gas tank sealing kit. I've used it to do some spot sealing on a tank...has worked well so far.
 
Go up to the search box and enter POR 15. You will find MANY MANY threads about opinions and techniques to use so that whatever you use works well. For me, I had excellent results with POR 15. Yes, as with most anything, one must follow the directions or one will have problems when you are finished. Did my /6 tank probably 5 years ago or perhaps 30 tanks of gas now through it with NO problems.....God bless......Dennis
 
I would definitely look into the Caswell Coating. It seems to have a large following in the Ducati world for sealing the plastic tanks against swelling of the ethanol fuels. I had my Multistrada tank coated last year with good results. European Cycle Services in NY has an excellent demonstration video on their web site. I also believe this is an FAA approved product.
 
+1 on Caswell - just did a Norton tank with their "dragons blood" kit and it turned out real nice and was pretty damn easy -'prep is the key, do all the steps exactly as they state.
 
I did mine last fall with Caswell. it came out great. follow the directions carefully. I have a R75/6 with the big tank.

Since I was not repainting, I wanted to stay away from chemical cleaning on the inside and used plain white vinegar.
I filled the tank with vinegar, let it sit for 24 hours and drained. (drained back into the gallon jugs the vinegar came in) at this point, the bottom 3" of the tank looked like brand new shiny galvanized metal. the rest of the tank had the original red liner, but it was very loose, and coming off. I then re-stopped the petcock holes (rubber plug with a screw init) and added hot water with detergent and 1/2 box of baking soda. then I tied a string to the middle link of about 4ft of small chain- like window sash chain- that I got from lowes. dropped the chain in the tank, tied the string around the gas cap collar, covered it with cellophane and a rubber band, and shook it well for about 5 minutes. pulled the chain out with the string (I would have never gotten gyp board screws or rocks or nails out with my gas cap collar) and drained the tank through the petcocks. At this point the tank was completely clean in the inside- shiny and no old liner at all.
I dried it for a couple of days inside, and with a hair dryer. then went on to install the Caswell. I used "petrol blue" which is kind-of turquoise colored. Make sure when you 'apply' it inside the tank, that the epoxy coating, the tank, and the room you're doing it in are all warm enough, otherwise the coating will be too thick and not flow well. I had a hard time getting it completely coated up on the shoulders at the top of the tank.
 
I have been told that radiator shops can clean out gas tanks. I have to wonder what is does for the paint.

Does your 91 have the PITA funnel in the filler neck? I'd guess that's going to have to get removed to use a sealer.

The OEM liner in my 86 is flaking off and both the Max BMW parts guy (Rusty) and one of their airhead techs advised me to use an inline fuel filter, but to otherwise not worry about it. I am going to remove the damn funnel from the fuel filler, but other wise I think I will take their advice and wait until I am going to have the tank re-painted before I re-line it.
 
Cleaning and rust removal inside the tank can be done with - molasses!

Works excellent and is safe for paint and inexpensive.
 
Well, gollleeeeee, never heard of that one before, but .. .. .

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