Flathead radiator leak
 

I have a slight weeping leak on one of the lower radiator hose outlets. Best I can tell it’s in the solder joint. I was going to take it to a radiator shop for repair but thought I would post here first to see if it possibly was an easy at home fix. If it is what type of solder would I use and what technique would be best?

Jonathan

Re: Flathead radiator leak
 

A Google search reveals lots of methods, solder and techniques.
https://www.google.com/search?q=radi...hrome&ie=UTF-8

Re: Flathead radiator leak
 

Best to take it out and let the radiator shop do the repairs . If you start putting heat on it, it can open up the solder joints and cause more leaks.

Re: Flathead radiator leak
 

Hell, I'd try to fix it myself first. If it works, it works. If it doesn't, trip to the radiator repair shop is going to be expensive no matter how you look at it. This is assuming that you're careful enough not to butcher it.

Re: Flathead radiator leak
 

The biggest thing is to rid of the repair area of any antifreeze residue . That means inside as well as the outside . clean thouroughly and sometimes can accomplish with a soldering iron.
It will take a bit of time to get hot enough to melt the solder.
Vic

Re: Flathead radiator leak
 

Soldering seems to be one of those jobs that scare people. It shouldn't. It is straight-forward and pretty easy. The areas being soldered must be very clean. If your leak is at the lower hose outlets, you may have to remove them, clean completely, and put them back. You don't need special solder; tin/lead solder is fine. You will need adequate heat. Most folks have soldering irons that are inadequate; you'll have to try and see how it works. A propane torch works very well once you learn to manage to get the right heat range.
As Tubman said, try it. You can always take it to a radiator shop if you can find one that does old radiators.
Good luck.

Re: Flathead radiator leak
 

I've had good luck in the past with a product called "silver solder". most auto parts stores have it. Just put it in and drive it a while. Wont hurt the heater cores.

Re: Flathead radiator leak
 

Have had heater core issue with Barrs rabbit pellet stop leak. Also have had great success with "Alumaseal". Most auto parts stores carry it. But here is a Amazon link for more info. Chap

https://www.amazon.com/s/ref=nb_sb_s...=1F5TZLU2FGBKP

Re: Flathead radiator leak
 

The key to any soldering is the flux you use to clean the area. I do stained glass work and I have fixed many radiator and heater core leaks. You need to drain the radiator (or remove a heater core). IF full of coolant, you likely won't get the area clean and the coolant takes the heat away. Now back to the flux. I noticed in radiator shops they use a liquid flux they apply with a brush which is the same thing used in stained glass work. I have successfully used my liquid flux bought at the stained glass store on brass radiators and heater cores. If you are not a seasoned user of solder, don't use a flame but an iron or gun with a LARGE head to transfer heat to the area after cleaning with a wire brush and painting on some flux, it will sizzle and do its job, then put some strong solder (50/50) on the area and it should flow nicely and not bead up.
Not rocket science. If it is a big area that needs resoldering, a shop is the best bet because they can immerse the radiator except for the area needed without fear of heat going where you don't want. My 2 cents.