How to repair hole in radiator.

Somehow I sprung a leak in my radiator. I suspect a bolt or nut flew off, hit my fan and flung into the radiator springing a leak. I took a picture of the spray. You can see it's not super huge however not a small trickle.

I personally normally work on air cooled engines so this is new to me. I would like to avoid replacing the radiator due to cost and time. I believe that I can access the hole fairly easily. It is a farmall H 1946.

You should be able to repair it. I would go ahead and remove the radiator, it will make it much easier.

The damaged area must be thoroughly cleaned, down to the bright brass. You may need to trim back some of the cooling fins to get to the damaged area. Scrape and sand, whatever it takes, it must be completely cleaned to have any success. Needle nose pliers and Emory cloth work well. If you can, try to pinch the damaged area closed. That will make soldering easier than trying to bridge a hole.

You'll need a propane or mapp gas torch, some flux, same as for plumbing, and if you can find any leaded solder, that is a plus, but if not, regular plumbing solder will work.

Bush on some flux, apply enough heat to flow the solder into the damaged area. The solder will only flow where flux has been applied, so be sure to work the flux into the damaged area.

The alternate method, if you don't want to remove the radiator, you can "try" to scrape it clean and work some JB Weld into the damage. About a 50/50 chance it will hold, may hold for years, may not work at all. The problem is, if it doesn't work, the epoxy will have to be burned/scraped out to solder it later.

If only a tube or two have been nicked it's an EASY repair.

Drain the coolant.

Grab a Dremel tool with a little wire brush in the collet and polish up the tube around the damaged area, tweaking any fins to the side that are in the way with a needle-nosed plier.

Apply "tinning flux", then grab a big soldering iron or a heated "soldering copper" and make the repair.

Unless you are experienced in radiator repair, like Advanced Steve, keep a torch and flame well away from the radiator, it doesn't take long to make things WORSE with a torch, unless you are very experienced, but repairs are easily made as I wrote, WITHOUT a torch.

I use a small backpack type oxy/ acetylene torch with the small brazing tip and silver solder. Get it clean and use stay silv flux.

I did JB Weld on a W30 radiator years ago. Hasn't leaked a drop in 30 years. A W30 radiator isn't pressurized and you have a nicer looking tractor so even if it works on a pressurized system you may not like
the look. I don't know if its paintable.