soldering radiator

[dragracer1199]

sorry if this is a little off topic,but what kind of solder is best for soldering a copper radiator? i have a radiator that has a slight leak in one of the seems.also any tips on soldering would be appreciated. thanks

[Mike W]

50-50 is good. Is that a seam on the tank top or bottom? You really need to clean up the area well. Sometimes a solder crack will have corrosion inside the crack. I use a hand held propane torch.

[dragracer1199]

50-50 is good. Is that a seam on the tank top or bottom? You really need to clean up the area well. Sometimes a solder crack will have corrosion inside the crack. I use a hand held propane torch.

it is on the seam on one of the sides.thanks for the reply.

[newtoit]

Talk about chasing your tail. Soldering a radiator seam seems to be about impossible. Like building an ice rink on an angle. But I have done it, much to my surprise. In fact, I have done it a few times. Seems like there is often a crust on top that melts much slower than the solder underneath. You get little volcanos. Melting the existing solder for a repair is problematic. Most likely you will have to clean out the old, and replace with new. The acid flux seems to work better, but the plumbers past flux works ok too. I do not care much for the newer fluxes that are gray ans are called tinning fluxes. Also, avoid lead free solder with a passion. It solders differrently. You will have enough problems trying to work what you have without introducing another variable. Good luck.

[hankj]

If it's copper, a 50-50 rosin core solder should do the trick just fine. IT HAS TO BE CLEAN, CLEAN, CLEAN! If you can't get it clean enough, you'll need acid core or acid flux. Copper does not like it at all, so be SURE TO FLUSH IT WELL if you wind up using acid.

Hank

[MigManiac]

I do these type of repairs daily and the best way to make sure it wont leak again is to remove the tank completely from the core and clean the seam mating areas. Use a torch and paste flux with solid solder. It seems like a lot of work but it isnt. As long as you have some common sense.