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Motorcycle tank repiar?

Posted: Sun Oct 12, 2014 9:19 pm
by Chipped tooth
A Friend of mine pulled a boner move on his bike, put to long of bolt in a place where a short bolt was supposed to go.

It put 2 holes in the tank behind the steel tab with the threads.

He used JB weld to fill the holes and it's working so far but will the JB hold?
I don't want him or his bike going up in flames !!!

I have never had any luck with JB and fuel.

Tank is clean no rust, not that old of a bike.

Looking for more of a permanent fix, New tank is insanely priced.

Re: Motorcycle tank repiar?

Posted: Mon Oct 13, 2014 4:52 pm
by Greenlight
If there is no rust, can you TIG weld it or braze it?

Several companies make gas tank repair putty. I have used this will good success.

http://www.walmart.com/ip/22296322?wmls ... 31&veh=sem

Re: Motorcycle tank repiar?

Posted: Wed Oct 15, 2014 9:11 pm
by Chipped tooth
I could probably Tig it but I don't want to ruin the paint.

It's gonna sit over winter with gas in it and see if it holds

Re: Motorcycle tank repiar?

Posted: Wed Oct 15, 2014 10:08 pm
by dave brode
This would seal over the jb, I bet. It works well. 8oz would be more than enough. Fwiw, I do two coats, back to back.

http://www.por15.com/POR-15-Fuel-Tank-Sealer_p_64.html

Re: Motorcycle tank repiar?

Posted: Fri Oct 17, 2014 11:33 am
by Chipped tooth
Thanks Dave, I'm guessing this coats the inside?

I wonder If it could be applied outside over the existing patch?

Re: Motorcycle tank repiar?

Posted: Fri Oct 17, 2014 11:56 am
by dave brode
Chipped tooth wrote:Thanks Dave, I'm guessing this coats the inside?

I wonder If it could be applied outside over the existing patch?
Yes, inside. It would not work outside. They sell a complete kit, etching cleaning etc, it's normally used on old rusty tanks. Iirc, they have a patch mat'l too. Afaik, the etching product is phosphoric acid. I'm cheap and just buy the coating. I've used concrete cleaner from home depot on not too rusty tanks. Followed by cleaning with purple power etc, hair drier after. You can look at their msds for a clue. I will say that with the phosphoric acid, the tank gets mighty warm.

Repeat: they don't recommend it, but I do two coats. I've done it several times with good results, including an old model T Ford tank. The stuff is pretty thin. Looks like metallic silver paint. Pour can in, slosh around for 1/2 hr, pour out. Repeat right away. It's good only for a few hours after can is opened. They say not to let it puddle, but I had it puddle, 1/2" thick or more in the bottom. Was still in there just fine after two year+.

Dave
p.s. - I had a quicky patch of fiberglass body repair stuff on a gas tank hold for years.

Re: Motorcycle tank repiar?

Posted: Fri Oct 17, 2014 7:15 pm
by Chipped tooth
I have done the quick patch before and it's holding still 3 years later, on a friend's RV.

This bike is efi with a module in the tank, I suppose I could pull the module and work the stuff around concentrating on the puncture area.

Re: Motorcycle tank repiar?

Posted: Sun Oct 19, 2014 10:48 am
by dave brode
info from garage floor thread. Would work as well or better than the concrete cleaner that I've used

http://www.homedepot.com/p/Klean-Strip- ... escription

Re: Motorcycle tank repiar?

Posted: Wed Oct 22, 2014 11:24 pm
by Chipped tooth
Thanks Dave

What's a guy use to get bad Varnish out of a tank from the 70s?
No rust just flaking heavy varnish..... I have never seen one like this.
It looks like molasses was spread around and let get hard.

So far Acetone and then Super clean hasent touched it

Re: Motorcycle tank repiar?

Posted: Wed Oct 22, 2014 11:35 pm
by dave brode
I 'spect that the phosphoric based stuff would cut it, that stuff is pretty nasty. I had dirty tanks that I fixed cleaned at a radiator shop [not sure what they use] and followed with phosphoric, then purple power, hair drier, then the coating.

Dave

Re: Motorcycle tank repiar?

Posted: Fri Oct 24, 2014 11:54 pm
by Kevin Johnson
Cough, cough --- probably highly illegal now --- cough, cough.

http://www.google.com/patents/US1113971

Re: Motorcycle tank repiar?

Posted: Sat Oct 25, 2014 2:04 am
by Chipped tooth
I would throw it in my hot tank if the paint wasn't good.

Re: Motorcycle tank repiar?

Posted: Sat Oct 25, 2014 8:06 am
by Kevin Johnson
Chipped tooth wrote:Thanks Dave

What's a guy use to get bad Varnish out of a tank from the 70s?
No rust just flaking heavy varnish..... I have never seen one like this.
It looks like molasses was spread around and let get hard.

So far Acetone and then Super clean hasent touched it
Sounds like a different tank from the original post. Are you sure that the bad varnish is not actually a previously applied coating? That would jive with it being difficult to remove.

Re: Motorcycle tank repiar?

Posted: Fri Oct 31, 2014 1:23 am
by Chipped tooth
I don't believe so, it only covers a little better than half the inside.

I was thinking of trying the airplane paint remover.

Re: Motorcycle tank repiar?

Posted: Fri Oct 31, 2014 10:04 am
by dave brode
Chipped tooth wrote:Thanks Dave

What's a guy use to get bad Varnish out of a tank from the 70s?
No rust just flaking heavy varnish..... I have never seen one like this.
It looks like molasses was spread around and let get hard.

So far Acetone and then Super clean hasent touched it
Speaking of molasses, you can find info on guys using feed grade molasses for rust removal. Hmmmm.

I've not tried it, but maybe it would do well on a tank? The molasses is said to work well on internal passages of heads/blocks and such. I have done the battery charger/washing soda [sodium carbonate], which works better with a little lye added, btw. Sorry for getting off topic, but the electrolyte and current works only with line of sight. Not so with molasses, afaik.

Dave