Topic: how to solder holes in gas tank

[tygrant]

my tank started leaking again. it was in bad shape and PO gobed on jb weld or something like that all over on side and on the bottom. I used a Kreem but didnt last a full season. my plans to strip out the krem sand off the jb weld and solder the holes then use POR-15...so has anyone soldered the holes in a tank? will regular solder work with a blow torch? thanks guys

[tygrant]

did you use regular solder?

[bwaller]

I have a couple soldering irons (or wands) although they are quite old, I've never seen them for sale anywhere. You heat the iron and then lay on the solder with it and don't apply direct flame to the tank. The tank needs to be very clean and use an acid paste just before the solder goes on.

I have also had a radiator shop do a couple really old tanks that leaked. He cleaned them in a hot tank, soldered the leaks then applied Red-Kote inside, all for $80.00 ea. Couldn't do it myself for that.

Something to consider.

[BobbyR]

Solder forms an alloy with the adjoining metal so it is really important that you make sure it is very clean in the spot the solder will be going. If you have some acid flux that will help also.

[tygrant]

i own a similar gun but i fugred since im painting over again i might as well hit it with the torch, i have alot of holes...

[Old Scrambler]

I'm with bwaller on the radiator shop.  My local shop drills the holes to get clean metal edges.  I recently had him do a later K2 tank with a baseball sized dent.  He drilled the dent, pulled it out, drilled three leaks that were really close together, soldered and brazed everything shut and put a primer coat on for less than $100.

[cb544]

Is there a specific type of solder I should use? I was told that the lead content varies with grade.

Also... I'm going to POR15 my tank... though I'm contemplating the fact that it has a hole in it. Should I de-rust the outside of the tank, drill & solder the hole and then soak the tank, or de-rust the outside of the tank, drill, cover with tape, soak the tank, and then solder once the metal is bare and brilliant on both sides of the flat. I'm leaning towards the latter, but would like to hear feedback.

- Adam

[midnightrider]

I have a couple soldering irons (or wands) although they are quite old, I've never seen them for sale anywhere. You heat the iron and then lay on the solder with it and don't apply direct flame to the tank. The tank needs to be very clean and use an acid paste just before the solder goes on.

I have also had a radiator shop do a couple really old tanks that leaked. He cleaned them in a hot tank, soldered the leaks then applied Red-Kote inside, all for $80.00 ea. Couldn't do it myself for that.

Something to consider.

What type of acid are you referring to?
Something like this?: http://www.handlaidtrack.com/Kester-Acid-Paste-Flux-p/SP-30.htm

Where do you think I can get it locally?

[Alan F.]

I think that's the same part number Kester flux that you can get at most hardware stores or home improvement centers... get the part number from your link before going shopping.

[bistromath]

Any hardware store will stock acid paste flux. It's the same stuff you use when soldering copper water pipes together.

As far as which solder to use, pretty much any will do -- regular eutectic lead solder is fine, and the newer "silver" solder (sometimes called "lead-free") will work, too. Silver solder takes more heat to melt, but is stronger when a good joint is made. If you've never soldered before stick to the leaded stuff, it's easier to get a good joint. Just clean it as best you can (I like the idea of drilling out the hole) and sand a small area around the hole. That will give plenty of meat for the solder to hang onto.

When sanding solder flat, WEAR A RESPIRATOR and wet-sand ONLY! You don't want to be breathing lead dust.

[Porscheguy912]

How big are the holes?
You'd be surprised what POR-15 can take care of.

About the solder. Get some silver solder from a Jeweler. You may be able to find it at a craft supply.
And FLUX, FLUX, FLUX!!
I had some photos of a job I did for a friends tank but i cant find them right now.

Also to  bwaller: The way I see it is if you dont apply heat to the tank, the solder will never bond to the tank. I can see the apprehension on heating the tank, IE: paint job and the possibility of an explosion, but it is necessary. Soldering is just like Brazing. You heat the metal to almost dark red then apply the solder to fill the hole.

I recommend rinsing the tank a few times with a de-greaser and then misting the inside of the tank with water before you start.

I'll try to find the picts to post...

[midnightrider]

Thanks - Im just learning so all of these tips help.  

I was at Northern Tool during lunch and saw this for $1.50 so I bought it:


Will this do the job?
It's made for sweating pipe, but says it can be used on a radiator as well so I figured it might work...

[VTCBike750]

my tank started leaking again. it was in bad shape and PO gobed on jb weld or something like that all over on side and on the bottom. I used a Kreem but didnt last a full season. my plans to strip out the krem sand off the jb weld and solder the holes then use POR-15...so has anyone soldered the holes in a tank? will regular solder work with a blow torch? thanks guys

So Tygrant, how'd things work out?

I love digging up old threads