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4 core Radiator Leak Advice

edgeoffroad04

Full Member
Joined
Aug 12, 2004
Messages
216
I have a JBG 4 core brass radiator that has developed a slow leak when running or sitting. This radiator is now 13 plus years old. Unfortunately the Bronco did sit for years during that time. Assuming this sped up the process of corrosion with the radiator(not changing out my fluids). Through out its life it has cooled and continues to cool the engine well(not great). With that being said what's the groups thoughts on Bar's radiator leak stop product? Knowing this isn't a long term fix vs throwing new parts at the Bronco.
 

EPB72

Contributor
Sr. Member
Joined
Jul 13, 2019
Messages
739
Loc.
Pleasant Hill, CA
It could work.. in fact all northstar Cadillac's used it in there factory fill and required 2 tablets when serving ,, Subaru also uses there stop leak additive as well.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
45,231
I've used Bar's, K-Seal and several others over the years and they have never failed to seal the small leaks. And in some cases, the K-Seal stopped bigger leaks as well.

And while "temporary" only (unless it works!), most of mine were at least semi-permanently fixed. I only replaced the radiator in one car after the lower hose neck broke off. Up to that point the leak had never reared it's ugly head again.

And some, including a top-of-the-line Bar's Leaks and at least a couple of models of K-Seal will successfully stop head gasket leaks of small size. Used it successfully in an Audi Quattro wagon once. During the initial drive you could feel it running smoother and idling normally again within ten minutes.

So yeah, even though I'm a fan of new radiators when called for, I don't usually hesitate to put the gooey stuff into the mix when it's needed.

Paul
 

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,879
if its a seam leak take it to the radiator shop to be fixed, if its a core leak then its pretty much a goner fixing it with fairy dust may work for a while but you will always worry about it. dont worry it will only fail on the worst place possible.
 

Broncobowsher

Contributor
Total hack
Joined
Jun 4, 2002
Messages
34,034
Roadkill approved K-seal head gasket in a can.

I fought a thermostat leak for over a year. Different gaskets. Even did an intake gasket in case it was leaking at that port. Different thermostat housing. Finally did the head gasket in a can after Roadkill claimed multiple successes with it. Fixed the leak. Didn't hurt the heater. Everything else looks to still work. Looking at the cores (not a Bronco, you can see the cores with the cap off) there was no sign of plugged cores. Call it a success. Not a fan of the chemical fix, but at times that is what is needed.
 

armynavy17

Contributor
Full Member
Joined
Jan 9, 2010
Messages
361
If you can pinpoint where it's leaking, you could try soldering it. I had to do this when I cut into the center of my less than a month old brass radiator while I was attempting to trim the fan shroud in place after installing a 1" body lift. I was dumb and in highschool (pretty much the same thing, right) and thought I'd save myself a little time. Drained the radiator, slapped on some flux, and soldered it just like a plumbing fitting. That was 10+ years ago now and it's still not leaking. Still cools great too.
 

Speedrdr

Contributor
Full Member
Joined
Nov 27, 2017
Messages
587
Loc.
Mississippi
Y'all are gonna laugh and shake your heads in disbelief, BUT when years ago, we would put ground black pepper in the radiator for small leaks. Don't know HOW it worked but it did workÂ…at least for a time. While I don't think I would prescribe this as a remedy, it will buy you some time.

Randy
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
45,231
No laughing from this peanut gallery! I've heard of lots of old "trail fixes" that were what people did back in the day. Oatmeal, dried mashed potatoes, raw potatoes, whatever you had to get you back on the road and your family safe.
You had to be more self-reliant even on the highways back in the day. Even roadside-fixes were kind of trail-fixes because there might not be anyone or any other resource around.

I've heard of the pepper thing working for others as well.
When you're at home and have the ability to remove the radiator to get it properly repaired, you don't need all that other stuff.
But under other conditions...

Paul
 

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,879
I used to carry solder seal (a metallic like powder) until it exploded in my getaway bag the plastic tube ruptured and sent the powder everywhere. extremely hard to clean up. it just smears everywhere.
 
OP
OP
edgeoffroad04

edgeoffroad04

Full Member
Joined
Aug 12, 2004
Messages
216
Really enjoyed reading some of the posts above(sorry I didn't respond sooner as I had issues with my account with the change over in the forums). I may need to add some pepper to my tool kit with the bronco. Ha ha

As for the radiator, my take away is Kbar may or may not work. Either way pulling the radiator over the winter is in the works. If I can find the leak, Ill try soldering it. If not I may attempt the Kbar fix in the short term. With a shiny new raditor as the last option.
 
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