GS450 Tank restoration

[MOC]

Since this is my first attempt at refinishing a tank I thought I would document it reasonably well.

I have a 1980 GS450L that had a nice dent on the right side of the tank about the size of a grapefruit. After much banging and wrenching and so on, I gave up trying to get it out. It was just not worth it. I went to a local motorcycle junker and got an identical tank in a different color that was dent free, but had some rust.

I used paint stripper and sandpaper to remove most of the rust, and then dipped the tank in an electrolysis bath to remove the remainder. This works remarkably well, especially if you orient the parts so that the heaviest rust is near to the electrodes.

After that, I discovered that some of the rust had made it's way through one of the welds that a PO had made to repair some earlier damage, so I patched it with some brazing solder and a pipe torch. After filing it smooth, I sealed the tank with some Caswell tank sealant, which is like maple syrup it's so thick. I chose to thin it a bit with some lacquer thinner just to make sure i got all the surfaces. I made sure to plug up the mounting holes for the petcock with tape so that they wouldn't be obstructed when I put it back together. The cured product is nice because it's hard but flexible. I had worried initially that it would be brittle and might crack if i dented the tank some time later but I'm confident it will hold up well.

Right now I'm in the process of fairing out the rusty spots and dimples, and prepping for paint. I've chosen to put some Underbody rust preventative paint on the bottom of the tank. It's not visible, and it's subjected to the most road dirt and debris. It's also where I found most of the rust (up by the front mounting grommets). Since I'm painting the tank black, it won't even be that obvious, and will resist wear at the points where the tank rubs the frame/wiring harnesses/brackets/etc.

I've also bought some high build primer and an epoxy paint for the color. I'm hoping it will hold up well to any fuel spilled and any heat it may catch as part of being above the motor. See the link below for a few pictures of the process. Hopefully I haven't missed anything.

http://flic.kr/s/aHsjDHBWzm

 

[MOC]

my apologies for the photo quality. My computer laid an egg a few weeks ago and i've had to do this all on my cell phone.

 

[Captain_Trips]

Going to have to do the same with my GS400 tank, looking at milkstone remover from Tractor Supply for the interior rust, though. Any thoughts?

 

[MOC]

I've been very impressed with how well the electrolysis has worked. if you can bend up a piece of steel piano wire like they sell at the hardware store you might be able to get into the corners. it's really a matter of how close you can get to the rust itself without bridging the two pieces. I HIGHLY recommend the Caswell product too. i got mine for 40 bucks, and it's really impressive. I've played with lots of resins over the years repairing boats, but nothing quite like this. If the interior of your tank is really really rusty, it might be worthwhile zapping it, then filling it with a fist full of quarters and shake it. Then blast it with phosphoric acid. The resin will adhere to whatever's been left behind and seal it in.

 

[Guest]

Nice work there, should work out well.

I used the POR15 kit on mine with great success too. I used some little rocks from the yard to shake and rattle around to get the loose rust off before starting with their process and it seems to have worked very well.

 

[MOC]

I used some little rocks from the yard to shake and rattle around to get the loose rust off before starting with their process and it seems to have worked very well.

This makes one hell of a racket when you do it but it's worth it. I wonder if there's a way you could adapt a chicken rotisserie to tumble a tank slowly for a few hours. It would make the process much easier, on your arms AND your ears.

 

[Nessism]

That milkstone remover is phosphoric acid and will work well. Home Depot also sells phosphoric acid in a product denoted as "metal prep". It will eat off all the rust inside and out in about 2 hours.

As Pete references, Por-15 paint works great for either sealing inside, or coating any remaining rusty metal, although I think Caswell's epoxy is better in my opinion if you have thin metal. The Por-15 paint would work great for the underside of the tank if you want to maximize protection. I used some on a rusty seat pan where even after sand blasting there was still rust down into the rusty pits. Good stuff.

 

[Captain_Trips]

This makes one hell of a racket when you do it but it's worth it. I wonder if there's a way you could adapt a chicken rotisserie to tumble a tank slowly for a few hours. It would make the process much easier, on your arms AND your ears.

A paint shaker could work too. That would be even louder though. lol

 

[eil]

There's a guy on YouTube who does motorcycle repair videos. Good guy actually, but some of this methods are... well, unique.

In one video he shows how to de-rust a gas tank by tossing in a bunch of old bolts, wrapping it well in blankets, and throwing the whole works right into the dryer for an hour or so.

Ah, here's the video: https://www.youtube.com/watch?v=i7I1O0K7EF8

 

[MOC]

I subscribe to that guy on YouTube. He's a really nice fella and actually use to live near where I live now. He knows a bunch of good places to find spare parts and tools. I think he's in California now. Either way, he's the guy that I learned the electrolysis technique from. You're definitely right though, his techniques are sometimes unorthodox. I'm not sure why he even bothered with the tank in that video. It looks like there was more rust in that thing than metal.

I spent some time sanding the body filler this evening and hope that I will be done by this weekend. With any luck the tank will be primed and a first coat of paint will be on it by Monday. More pictures to follow Thanks.

 

[MOC]

Got the undercoat and Color down. 1 more coat of color, then color sand, clear, and polish. so far so good:

I used VHT epoxy paint for the color. It works wonderfully. Nice and hard, quick to dry, and it's not as bad of an orange peel as i expected.

 

[MOC]

Clearcoat and Sanding materials

After wetsanding, during the buffing process:

after buffing and a coat of McGuiars wax:

 

[Guest]

Nicely done!

 

[Steve]

This makes one hell of a racket when you do it but it's worth it. I wonder if there's a way you could adapt a chicken rotisserie to tumble a tank slowly for a few hours. It would make the process much easier, on your arms AND your ears.

I know a guy that wanted to de-rust the tank on his old GoldWing. He put the usual handfull of gravel in it, wrapped it in foam blocks and stuck it in a small cement mixer.

He said that he had to change the orientation a couple of times to ensure that all the surfaces were "treated", but it worked great.

The foam helped deaden the sound, and the mixer was at the edge of the property, next to the neighbor's corn field, so noise was not a problem. :-\\\

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