Clean, clean, clean is my advise. I've repaired similar before but imho it's a crap shoot at least in my case. You don't want to aim your heat on the tank as the tubes are soldered in and you'll end up melting it out somewhere else.
Small wire and a small tungsten is a must as well, I used .035 from a spool, I tried both 4043 and 5356 and had better luck with the 5356. Here's hoping someone else will chime in with some more advice....Mike

 

That is very tough to do..
I have done them in the past and found that if you squeeze the tube together with some needle nose pliers your chances improve a whole bunch to get it done..

You do NOT want to try to fill in the hole itself..
CLEAN CLEAN CLEAN it first with acetone and a stainless "Toothbrush..
Pinch it together as best you can then just weld up the "Mass"...

It's not EZ but can be done and don't rush it..

...zap!

 

Yes you could tig it, or you can do what most radiator shops do and braze or solder it. Allstate 31FC is a popular brazing material, and Harris Al Core has been a popular soldering material. Zap is right though, normally the area is pinched shut first reguardless.

 

There is some missing information here - such as what type of radiator you are talking about.

There is a simple 2 core radiator and there is Double Pass radiator. The double pass ones - you shouldn't crimp off the flue.

You also have to understand that the flues are furnace brazed, where they put the radiator inside a furnace and they heat it until the flues melts to the tank. When you start heating that stuff up - you run into a whole mess of problems.

Places like C&R racing radiators has a shop where you can send a radiator to be repaired professionally. It usually requires the flue to be removed and replaced.

The only other thing you could do would be to cut the flue at the tank, Cut the flue about a inch away from the tank. Weld each piece solid and pressure test it to make sure that it does not leak.

 

There is some missing information here - such as what type of radiator you are talking about.

There is a simple 2 core radiator and there is Double Pass radiator. The double pass ones - you shouldn't crimp off the flue.

You also have to understand that the flues are furnace brazed, where they put the radiator inside a furnace and they heat it until the flues melts to the tank. When you start heating that stuff up - you run into a whole mess of problems.

I believe it to be a 2 core. Fluid flows from top to bottom and back cycles into the engine. The radiator is completely made out of aluminum as well. I know the brass/plastic radiators are furnaced to melt the flues, but I am unsure of all aluminum radiators manufacturing processes.

I have fixed a bunch of aluminum radiators and oil coolers, usually much bigger than what you're working on. What I do is cut a section out of the tank on both ends of the leaking tube--sawzall works great--then weld the tube shut from the inside and weld the tank sections back on. Like I said, they have ALL been much much bigger, but has worked for me very well.

Im sure the larger the size the easier it was to work on! haha. The core for this radiator is about 2 inches thick. Makes the space a lot tighter. If I commit to this method, I will probably have to cut out a pretty large section just to get access to the leaking flue.
I definitely will try to avoid this process, although it looks like its my only option.

This is probably a candidate for a cold (epoxy type) repair. The trouble is, the radiator belongs to a customer of a customer and it probably will be difficult to monitor the repair's success.

With all that being said, it looks like Project7Studios is working on an expensive custom radiator, complete with welded tanks... maybe it should go to a radiator pro.

I have read of a method using JB Weld with a thinning mix to make it flow a bit easier. I pinch the flue, mix the JB weld, Mix in a bit of mineral spirits (or laquer thinner, i forget) to make it more viscus/loose and then pour it all over the pinched hole. The JB weld is supposed to create a total seal over the hole by penetrating past it but it also renders the surrounding area of the radiator useless by blocking air from passing through.

Has anyone tried this method?

I am worried now that this might be something for a professional. Thank you all so much for your knowledge!

 

I have fixed a bunch of aluminum radiators and oil coolers, usually much bigger than what you're working on. What I do is cut a section out of the tank on both ends of the leaking tube--sawzall works great--then weld the tube shut from the inside and weld the tank sections back on. Like I said, they have ALL been much much bigger, but has worked for me very well.

 

Low temp staybrite silver solder and liquid flux, like the previous post said though crimp the damage first, and clean it. stuff is found at most jewlery supply places. I use it quite a bit for rads and welding repairs.

 

This is probably a candidate for a cold (epoxy type) repair. The trouble is, the radiator belongs to a customer of a customer and it probably will be difficult to monitor the repair's success.

As far as a hot repair goes, if practice on a scrap radiator proves that the repairman is proficient at tube soldering, then soldering the injured tube could be attempted. Of course followed by a pressure test and in-service monitoring.

If you can't master tube soldering, the injured tube should probably be abandoned and its openings in both headers closed.

Per this method:
View attachment 54561
But that was simple lead soldering of brass radiator.

Myself, I don't know of any silver solder alloys that will bond with aluminum, and have only had limited success with aluminum solders, so for me, I'd say it'd have to be a weld at the header. But then heat control would be critical to prevent adjacent tubes from loosing there bond with the header. So maybe the latest greatest solder would deserve the old college try.

Whatever the method, you'll have to start with extracting the damaged tube, leaving a clean header opening to work with. Start by neatly cutting the damaged tube, but first warm the fins to break their bond with the portion off the tube that will be removed -and now the tough part- gently warm the header so that the cut stub of damaged tube can be pulled from its socket. Then it's clean clean clean.

With all that being said, it looks like Project7Studios is working on an expensive custom radiator, complete with welded tanks... maybe it should go to a radiator pro.

Although if anyone has some proven sure-fire aluminum soldering tips, we'd sure like to see/hear 'em.

Good Luck

 

My friend and I used a putty called "Quik Metal" to fix a leaky gas tank on his old junker truck. I thought it would never work but several months after we put it on there, he said the truck wasn't leaking gas at all. If it can stand up to gasoline, it must be good stuff.

 

JB Weld works well for radiator type repairs. I've used it to build up and repair pinholes in a corroded magnesium water pump housing. I initially used a typical fast cure epoxy which failed quickly. Upron reading the product data sheet I saw it had a max temp rating in water of 120F. The surface was even bead blasted and I was able to simply peel out the old epoxy. I did it again with JB Weld and it's lasted nearly 2 years and is still going.

 

[ame]http://www.youtube.com/watch?v=NUTdeDBl0Ac[/ame]

 

If you attempt to TIG it, consider that the thickness of that tubing could be only .020" thick. That was the thickness of the tubing of an intercooler of similar (welded tube) construction to that radiator that I worked on. Better practice welding on some pop cans! (and get good at them too!)

I would use a low melting temperature (700 F or so...) zinc-aluminum brazing/soldering rod for that application, heated with an oxy fuel torch, if you have access to it, if I were you. It will be much more reliable than an epoxy repair. But if you were to go with an epoxy repair, I would go with one of the ones with metal filler in it, such as the grey marine tex, or JB weld. Any epoxy will only hold well if you can roughen the surfaces before application with an appropriate "tooth" beforehand, such as by sanding.

Although TIG might be fun to try just to see if you can do it. Practice on some aluminum cans first... welding .020" material is a matter of fine control of the welding current on the low end. Use a small electrode like .040" and maybe 1-2 dozen amps. If you have trouble making a fine adjustment of the current knob in the very low range, you can make a fine adjustment of heat into the part by adjusting the AC balance, if you machine has that setting (turning up DCEP / cleaning setting will put less heat into the part, kind of like turning the current down by a little bit). And also rather than reaching for a common 1/16" TIG filler rod, you may find using a smaller diameter MIG wire more suitable for precision dipping. Hope this helps and good luck!

Also for TIG, yes aim your torch at the thicker header plate / end tank, as it will soak more heat away than the thin tubing. Intercooler I worked with of welded tube construction had .050" header plate, with .020" tubing wall thickness. This radiator looks of similar construction. And it is likely that the braize material holding the tubing to the header plate melts only a few dozen degrees lower than the parent metals, which you would not notice any difference between when TIG welding.

 

If you attempt to TIG it, consider that the thickness of that tubing could be only .020" thick. That was the thickness of the tubing of an intercooler of similar (welded tube) construction to that radiator that I worked on. Better practice welding on some pop cans! (and get good at them too!)

Although TIG might be fun to try just to see if you can do it. Practice on some aluminum cans first... welding .020" material is a matter of fine control of the welding current on the low end. Use a small electrode like .040" and maybe 1-2 dozen amps. If you have trouble making a fine adjustment of the current knob in the very low range, you can make a fine adjustment of heat into the part by adjusting the AC balance, if you machine has that setting (turning up DCEP / cleaning setting will put less heat into the part, kind of like turning the current down by a little bit). And also rather than reaching for a common 1/16" TIG filler rod, you may find using a smaller diameter MIG wire more suitable for precision dipping. Hope this helps and good luck!

Also for TIG, yes aim your torch at the thicker header plate / end tank, as it will soak more heat away than the thin tubing. Intercooler I worked with of welded tube construction had .050" header plate, with .020" tubing wall thickness. This radiator looks of similar construction. And it is likely that the braize material holding the tubing to the header plate melts only a few dozen degrees lower than the parent metals, which you would not notice any difference between when TIG welding.

Practice on pop cans... Ugh. I seemed to always blow through them. I dont think my skills are up to par with this repair simply welding on the flue. I thought about just heating the tank and then creating a puddle with filler that would just kinda melt over and into the hole, but now Im worried about blowing through the flue.

I think instead of TIG I should practice with the Oxy/Act torch...

The MuggyWeld flux definitely looks interesting.

+1 on this. MuggyWeld definately does look interesting.

Has anyone used that product here?

 

I've seen the TV and carnival demonstrations of aluminum (zinc) solder making all sorts of repairs, but I've never had any luck with it except on the bench with a simple flat test plate.

The MuggyWeld flux definitely looks interesting.

Good Luck

 

My vote?? Pinch it, clean it to the moon, and then using a small wire brush, scrub/ roughen the area so the JB Weld has a bit more surface to bite to. Don't thin it; it will flow enough in it's viscous form. Stir it up for several minutes, it sets off a touch faster with the extra mixing. As was stated, the corrosion factor makes aluminum really tough, and possibly really thin wall.

 

I think I am going to use this method. It sounds like the most successful and the least risky of all the methods discussed.

I fear that TIG will just ruin the flue and potentially ruin the radiator completely. Brazing/soldering sounds like it might work but with lots of practice. Practice means that I need to have an extra radiator made of full alum and braze/solder rods which I have neither of. One day though, I would love to have the opportunity to try to actually weld something like this with the TIG or Oxy/Act.

I will return to post pictures and results sometime next week when I get around to the actual repair. Thanks for everyones replies and please continue to offer ideas and suggestions!:blob3:

 

Dave powelson - I've got a late model, aluminum automotive radiator core in the garage with its plastic end tanks removed. (Original, used radiator from a 2001 Ford Focus, which had inexplicably developed a tiny pinhole leak.) I measured the tubes that were sticking about 3/8" or so through the header plate using digital calipers, and saw measurements varying from .016" on the thinnest tube (the "outlier"), to a more common .018-.020", and up to about .022" thick on the thicker spots.

 

Boy that muggyweld is expensive. Most of the radiator shops around here use Harris Alcor, which is a zinc based alloy and is flux cored. Another popular one is BTI soldercraft 780. Alcor is about $20 a spool. [ame]http://www.amazon.com/dp/B002Z5Q7SC/ref=asc_df_B002Z5Q7SC1220711?tag=stylefeeder-20&creative=395261&creativeASIN=B002Z5Q7SC&linkCode=asn[/ame]
-Aaron

P.S. I forgot Harris Al-solder if you want a low temperature material. I think muggyweld is just a re-packaged Esab product.

 

Thought I would share a repair I did the other day
my first attempt on a radiator tube I did a little practice weld on a soda can first hole in right tube 2/3's from top of weld the rest to buildup smeared tube
was done at about 18 amps balanced .040 tungsten .035 filler

 

Whoa! Looks great! Pressure tested fine too Im assuming!

Wanna drive to Dallas and weld mine? haha

 

I had one spot that weeped,easily fixed. If I ever do another one I will give it a little more pedal as the puddle cooled real fast with the .035 and didnt lay down as nice as it could have.but never done one b4 so I was a bit conservative with the heat.
Project7Studios, on yours being that close to the header if it is epoxy joined at the header the heat will most likely destroy the tube connection forcing you to cap off both sides of that tube I would use a good two part epoxy to fix the hole on the one you have

 

Project7Studios, on yours being that close to the header if it is epoxy joined at the header the heat will most likely destroy the tube connection forcing you to cap off both sides of that tube I would use a good two part epoxy to fix the hole on the one you have

Very good point. It looks like Im going to be using epoxy!

I should have posted this on the epoxy forum perhaps? :laugh::laugh:

 

Super late update but the epoxy worked! Jb weld worked great

I mixed it and shoved it down into the space around the hole as much as possible. Placed the radiator in an angle that would use gravity to optimize the coverage of the epoxy into/on the hole. Allowed it to dry, pressure tested it and bingo! Hole sealed!