• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Coolant leak

Big T

Well-Known Member
Messages
11,937
Reaction score
26,419
Location
Fullerton, CA
I have this stubborn coolant leak since installing the new Champion radiator last fall. It is on the passenger side and appears to be coming from the fitting from the upper hard line (pencil in picture pointing to the line of coolant leaking from the fitting):

5618E510-6DF0-481D-B399-84829C8864D5.jpeg

It’s easier to see the coolant line when you flip the pic upside down. The leak shows when it’s been sitting, particularly in the current freezing cold weather.

What is this line for and how do I get it sealed up?

I will note that I have replaced all the rubber hoses over there as part of chasing this leak down.
 
Have you pressurized the system and watched? Have you added stuff to glow and then used black light?

Also, no one likes to think a new radiator is cracked, but that’s what warranty is for.

Pressurized from running it to operating temp, but really don't see the leak then. No to glow stuff and black light. Really have traced it to that fitting because there is a dribble trail from it. Last ran the truck on Sunday. Shoved a large piece of cardboard under the engine bay and today I noticed a large spot of coolant and the dribble from that fitting.
 
I'm gonna guess that line is your tranny cooler and the seapage is coming from the weld on the radiator. cold temps cause metal to shrink. it's possible the weld on the rad has a tiny pin hole that once warm it seals itself. I would think maybe pressure test it when cold. if it's past the warranty and the weld is the issue, the only fix would be to take the rad to a radiator shop or a good welder who can do aluminum and have them re-weld it
 
I'm not fond of all aluminum radiators, I wish I could get an all copper one like they used to use in the old school vehicles. when a leak sprouts those can be soldered up quite easily.
 
I'm not fond of all aluminum radiators, I wish I could get an all copper one like they used to use in the old school vehicles. when a leak sprouts those can be soldered up quite easily.

Minor correction... I'm not aware of any all Copper radiators, but I am aware of brass radiators from yesteryear. A little flux and a silver dime as solder and anything could be patched in an emergency.

I re-cored my old radiator on my H1 with brass, 4 core dimpled. I replaced my HMMWV radiator with a new OEM brass unit.

Perhaps you could re-core your old unit? I suggest 4 cores and dimpled tubing to break up laminar flow and enhance heat exchange and cooling.

IMHO
 
I meant copper lol only trouble with mine, it's the infamous plastic junk tanks with the aluminum core! one of these days if we do find a yesteryear radiator (junkyard find) that fits and works without limiting cooling, I will be all in! haven't looked into it, but maybe the older trucks with the big block 454's would work.

this would also alloy us to eliminate that plastic surge tank with the pressure cap and have the radiator cap on the actual radiator!
 
I'm gonna guess that line is your tranny cooler and the seapage is coming from the weld on the radiator. cold temps cause metal to shrink. it's possible the weld on the rad has a tiny pin hole that once warm it seals itself. I would think maybe pressure test it when cold. if it's past the warranty and the weld is the issue, the only fix would be to take the rad to a radiator shop or a good welder who can do aluminum and have them re-weld it

Isn’t the tranny cooler in front of the radiator?
 
Haha, yeah they are sick of me saying copper with dimple cores here also.

the part that makes the difference is the hummer tax.
idk what yours cost on east coast, but mine was close to 900. Erics was 800 for his hmmwv and was not dimple core.

The difference is our tanks are brass factory and pickups are plastic tanks. Having the tanks made copper or brass probably 250 themselves to custom make then you could add 700 or 800 on top of that.

With the new factory radiator sold for $900- and aftermarkets were $1100, an easy choice.
But comparing those price to available options for the pickup- it jus doesn’t make sense.
Getting the aluminum one already coated from Chris becomes the best choice.
 
The warranty for the radiator is covered by Champion, I cover the coating warranty..

@Big T if you need to contact Champion they will want when and who you purchased it through and they will lead you through the warranty process.

No coating on this.

Would resetting that fitting with Teflon tape help? Or is it cracked?
 
imo resetting the fitting would only fix a tranny fluid leak at the threads. I would clean the area off real good and watch for a bead of coolant in that area if no access to a pressure tester, do you have a camera to put there on a close up and live record if for a while, when it begins to leak look for where the first coolant droplet forms at.
 
Back
Top