Topic: Gas tank rust - how many pin holes is too many? Tank shop grenaded my tank

[slikwilli420]

I have a bunch of pin holes on various places on the bottom of a super sport tank in using on my race bike. Will caswell's seal all of them ok? Going through the process of derusting and they keep popping up. Thoughts?

[PetesPonies]

Use Master Series Silver. This is a moisture cured urethane primer that is impervious to gasoline. It has many other uses, but works wonderfully inside and outside on gas tanks. I pour it in and turn the tank every way  to get a good coating withg a rusty tank. If you feel you don't need it everywhere, you could just pour it in the bottom. It doesn't peel, so you don't have to worry about some tank liners peeling. Trust me.

[slikwilli420]

So it's not actually a tank liner? I've never heard of this stuff. How does it compare to Caswell's? I've never heard of a Caswell's failure and it's a known good product.

[Tews19]

Do you have a pic. My super sport tank had a lot of pinholes. Caldwell worked great!. Lasted 3 years w no issues

[Stev-o]

+1 Caswells.....sealed the pin hole in my H1 tank.  I get it on eBay.

[PetesPonies]

I said it is a moisture cured urethane primer. It is not marketed solely as a  tank liner. It is a primer. But it seals. It is thick and has aluminum in the mixture. A pin hole is easy for it to seal. But can be used where a rusty inside hasn't caused pits yet as well. I use a lot of it in restoration work. I have used it in bike tanks and car tanks.

[bwaller]

Check with radiator shops and find someone that will solder the tank and test it after. It'll be sitting over a very hot revving engine, you need to trust nothing bad happens when you're going a million miles an hour.

[slikwilli420]

Brent for the win. Heading to a local radiator shop for a full check up. The gent on the phone quoted $75 for a pressure test, repair, and second pressure test. I will still be lining with Caswell's but I like the idea of additional insurance for these things. The radiator repair idea never crossed my mind since I assumed it was far more expensive. Never hurts to as I guess. I'll let everyone know how it goes. Dropping off Friday and picking up next week.

[calj737]

I'd offer this: Caswell is a great product, but in actual fact, it adds a noticeable amount of weight. If you are having a radiator shop repair the tank, skip lining it. This race bike will see regular maintenance and you should not experience issues of on-going rust once removed, cleaned, and used.

Or, skip the radiator shop and line it. But no need to do both in my opinion.

I've not been able to find a local shop to do this service for me, so I've had to repair them on my own and line them 

[Stev-o]

I contacted a radiator shop a couple years back about a rusty tank.  My tank had nice original paint, he said he could not guarantee there would be no damage to the paint so I skipped it and went the vinegar route.

[slikwilli420]

Ive had mine soaking in vinegar for the last few days, and it seems to be revealing more pin holes and getting some rust out but I am underwhelmed overall with progress. Hopefully for the radiator shop will be able to cure all that ails me regarding this tank. I really don't have a backup plan for a tank so this one needs to work out. I am still well under cost of a new glass tank and I am OK with that for now.

Cal, they pressure test afterward so I will just make sure its squeaky clean inside and go from there. I will also be running race gas which is far more stable than street gas and not hygroscopic since it contains no ethanol.

I could also run a nice bronze reusable filter, but that seems to be a polarizing topic, so I will need to ponder that one.

[calj737]

Cal, they pressure test afterward so I will just make sure its squeaky clean inside and go from there. I will also be running race gas which is far more stable than street gas and not hygroscopic since it contains no ethanol.

Precisely! Save the Caswell for your street bike 

[PetesPonies]

The epoxy by Caswell has lifted in some cases. You never know about the application procedure for sure . .but it has been documented to have failed. I take Phosphoric acid and leave in the tank for a couple days. I turn the tank from side to side to get it all. Then pour it out, rinse and when dry, pour in the Master Series.

[Terry in Australia]

Yep, I've read about Caswell failures here and on other bike sites, and experienced a POR-15 failure first hand, so I think all tank liners should be treated with suspicion. Having said that, if you've no other alternative, as long as you follow the directions religiously, you should get a good result. F tanks are rust magnets..........

[Jerry Rxman Griffin aka MuthaF'er]

If you're getting pin holes from vinegar (MILD acid) I'd suggest you NOT go with anything stronger like phosphoric acid at this point unless you want a sieve. Hoping the radiator shop lining repair will take care of it for you. Don't re-line their fix.

[Geeto67]

Red-kote:

https://www.amazon.com/Red-Kote-Quart-Sealer-Diesel/dp/B009X0JOSM

when I worked in a rad shop this is what we used to patch holes in the tanks of industrial equipment. It basically makes a flexible bladder inside the tank. I once used it to line a glass tank that later cracked and fell apart - the liner still held fuel even though the tank was no more. When we used it with tanks that had pinholes we wouldn't even solder them up.

A word of caution - if you screw it up the only way to remove it is to burn it out with a torch which will pretty much ruin your tank too, so take your time.

 

[ekpent]

 I've used Red-Kote with no problems. Still have a quart or two around. I buy from this guy in Florida, $24.95 + free shipping    If it was me and the holes did not get soldered or patched with metal I would at least lay a layer of JB Weld over them and let it cure well and then go with a nice good coat of the Red-Kote. I know the JB may not be the best fix but in a perfect world no gas will get to it through the red-kote and it offers a little extra insurance and rigidity. Fixed one this way quite a long time ago and its still around. Paint was way to nice to trash it out.   http://www.ebay.com/itm/RED-KOTE-GAS-FUEL-TANK-SEALER-LINER-REDKOTE-QT-/282331280531?hash=item41bc417493%3Ag%3A%7EpkAAOSwEK9UDcTd&vxp=mtr&nma=true&si=sDHLnFPDJJokz51%252BBSgBTkJTxfg%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

[bwaller]

Matt I've had several soldered, one rare tank damn near had a full layer of solder underneath, talk about adding weight. Every time they were very rough inside so they received Re-Kote including the first tank I used on the racebike, a 400F. The rad shop always did the RedKote after they were dipped in their tank. Early on I ran a 50/50 mix of C12 & pump gas and never had an issue with the coating, but I always drained the tank immediately after the weekend. Clean interior and no lining or filter is king though!

Be forewarned about race gas, some are corrosive with combustion. Not sure, it may only be the leaded fuel but regardless it's wise. As soon as you're home use a remote tank and run the engine on some pump gas, then drain the carbs of that #$%*.  My experience was a delayed end of season teardown and difficulty getting the plugs out because of corrosion. Nearly ruined one plug thread. Now I heat it up on non race gas within a day or two.

[eigenvector]

If you can find a radiator shop that will do the work - congrats.

I tried a while back for my 550 tank and pretty much all of them acted like I was asking if I could borrow their cash register for a couple of hours.

I think in larger cities they have enough work to not need small jobs like this.

[754]

Soundslike you could get away by riviting a tank together, then sealing it.
 Slick I got an idea for anyone that is a good welder..section the tank..take 3/4. Inch off the bottom, make a lower piece, weld it up.. Smaller tank on a racer should work.
 The vinegar is only revealing what is really wrong in there.

[BRAD CHIEDUCH]

I took a tank in and had it chemically stripped which revealed some pin holes at the base of the tank.  Certainly no coincidence the pin holes were on the left-hand side of the tank - leaning while on the kickstand caused water/corrosion to only develop on this side of the tank.  The holes were TIG welded shut (20 amps, 0.030 mig wire, 1/16" tungsten electrode) and then the tank was internally coated with Red Kote.  Red Kote is the only product I would ever use for sealing a tank as it has served me well over many years and many different bikes.  There may be other products that work equally well but it has worked for me so why change.  I can say one thing for certain and that is avoid the cream tank liners like the plague - these products are absolute garbage!!

[Terry in Australia]

The problem with pin holes is that they're pin holes on the outside, but craters on the inside. I wonder if you could flux and solder the craters from inside a tank by applying heat from the outside? I'd still add a liner as some extra protection, but I'd still be concerned about a paper-thin tank rupturing in a crash.

[BRAD CHIEDUCH]

Terry, soldering is soft material and has a tendency to work harden and become brittle when stressed.  In addition, solder  does not fuse with the parent metal of the gas tank.  Brazing works better than soldering and will stand up to higher loading - in fact you will see the petcock bungs on CB tanks are brazed.  If you are worried about a repair area springing a leak in a crash your best bet would be to TIG weld the holes as this provides fusing with the parent metal or better yet ... don't crash!   

[przjohn]

I think we can put Tank Lining Kits in the same boat as Tires and Oil for internet opinions.

[BRAD CHIEDUCH]

I'm sure there are many opinions from the DIY folks but based on my experience the majority of radiator shops only use Red Kote for tank sealing.