How to fix radiator leak

[Edahall]

My radiator appears to be leaking where one of the tubes is soldered into the tank. How do I fix this? Soldering? JB Weld?

[mongocanfly]

Buy a new one..that's what I did..got one from oreillys cheap as the quote to "try" to fix mine...

[Jstock85]

JB weld. if that does not hold then just get a new one.

[Edahall]

This is a 4 core radiator with copper tanks for heavy duty applications. Who sells a similar radiator for low cost? I don't really want a radiator with plastic tanks since vehicle is used for towing in very hot climates.

[BLT gmc]

If you can get to the leak, clean it very well, use flux and sweat in some solder. Bruce
Posted via Mobile Device

[Peter S]

Originally Posted by Edahall

This is a 4 core radiator with copper tanks for heavy duty applications. Who sells a similar radiator for low cost? I don't really want a radiator with plastic tanks since vehicle is used for towing in very hot climates.

That radiator is definitely worth saving. The correct way to fix it would be with solder....just make certain that the area is clean.

If you have an old school radiator shop still in business, they should be able to boil it, fix the leaks, pressure check it, and paint it.

[Matt Man]

My truck had a Harrison radiator in it when I bought it. I went to a "old school" shop and they wanted over 400$ to re-core it I bought a spectra from summit for 104$ and it does fine in the California desert heat.

[Dead Parrot]

Keep in mind that if that radiator is fairly old(20+ years), other leaks may be a short time away. You could wind up playing a version of whack a mole with leaks. How many times do you want to drain coolant, pull the radiator, clean, repair, reinstall, and refill?

2nd Peter S's suggestion on a old style radiator shop. See if and what they charge for a good test.

Might try some stop leak. I used some when my heater core started leaking after winter cold had started. Delayed the inevitable about a year and a half. At least it was spring when it gave up.

[Bandit130]

Good luck if you can find a radiator shop that would attempt to re-core. The original radiator on my 74 was not leaking, I wanted it re-cored and could not find radiator shop that would touch it due to it did have previous leaks repaired. When they saw the greenish color from past leaks, they said no way. Ended up replacing with aluminum a few months ago, no problems since here in Texas heat.

[mongocanfly]

I had the old school radiator shop look at mine...they said maybe maybe not..couldn't guarantee it..mine wasn't leaking but you could look down thru the fill hole and see the flutes were stopped up...it would take 15-20 min to drain it...it was still cooling I just wanting it cleaned..they said cleaning may cause more problems than its worth...aka wackamole...I got a wide core aluminum from O'Reilly for just over 100 bucks. ..it cools fine and Im pulling a 9k loaded trailer in alabama heat...my temps never get over 185..

[akart]

My truck had a plastic one and I wanted a copper/brass one. Looked like 600.00 new and shipping but I went to the salvage yard found one that looked for a "C" note. I'm happy.

[superdav]

Originally Posted by BLT gmc

If you can get to the leak, clean it very well, use flux and sweat in some solder. Bruce
Posted via Mobile Device

This, its cheap and harbor freight sells some soldering rods that work great

[Edahall]

Do these low cost plastic tank radiators cool as well as these old school 4 core brass tank radiators? I've got a diesel engine in my truck and it needs every bit of cooling possible.

[mongocanfly]

Mines not diesel...but it was a 350 and now its a 6.0 lq9..new radiator cools just fine..like I said pulling a 9000 lb loaded trailer...a diesel may be a different story

[Edahall]

Thanks for the replies. Instead of fixing this radiator, I picked up a used radiator out of a 1984 diesel Suburban for $50. It looked a lot better than mine and I found no leaks when I did a pressure test on it. Not sure if it was replaced at one time or not but I notice that it doesn't say Harrison on the side of the tank and it has a plastic drain plug. My guess is that it has been replaced.

I might have been alright with a new plastic tank radiator but plastic worries me because my experience with them is that they don't just start leaking slowly, they crack big time and leave you stranded on the road. My area has very hot temperatures and those with the newer trucks complain about their plastic tank radiators blowing up.

I am going to give this radiator a good cleaning before installation. Then I will try soldering my leaky radiator.

[Edahall]

This used radiator that I acquired was full of scale. So I poured a gallon of Muriatic Acid and let it set for about 30 minutes. Many big chunks of scale came out as I flushed it out.

Before


After

[Edahall]

Used radiator has a leak in one of the tubes. This was on the side with the grill so I most likely missed it when I performed the pressure test. The leak is also behind the metal band which may have worn through the tube over time. Can this leak be soldered?

[Tash4]

Cleaning an old one like that may have caused the leak. Soldering may be tough in that spot. Good luck with repair.

[DieselSJ]

Originally Posted by Edahall

This is a 4 core radiator with copper tanks for heavy duty applications. Who sells a similar radiator for low cost? I don't really want a radiator with plastic tanks since vehicle is used for towing in very hot climates.

Meh. That is old tech. 2 big rows cool better than the old 4 small core units. My 87 came with an aluminum with plastic tanks and I have zero issues keeping my 454 cool with A/C on full blast towing 8K lbs through AZ.

These 800hp desert race guys have gone to aluminum 2 core units. If you are scared of plastic tanks then call up Ron Davis and get one with welded aluminum tanks. That is what I have in my Jeep and again zero cooling issues.

[truckin 79]

Most modern trucks have plastic side tanks and have performed fine. I have a GMC 2000 sonoma and replaced radiator a couple years ago. I think 15 years was not bad for a 173,000 mile truck. I also had used Bars leak in it since the leak developed in the winter time and I did not want to mess with it till it got warmer. I will say bars leak works pretty good and have even heard a raw egg works as well lol. I would trust bars leak over an egg though, ran bars leak in a NOva for 2 years. Anyway I digress a plastic radiator I bet would be cheaper and less frustrating in the long run but good luck.

[Dead Parrot]

If you are decent with soldering copper pipe, should be able to fix the leak on the 2nd radiator. Just clean the outside real well. Might help to cut out a couple of the fins around the leak. At this point, you don't have much to lose. If nothing else, just crimp shut that row at the leak and solder the crimp.