My radiator blew up

[Daniboyoh]

04 TJ Rubicon

So I'm sitting a parking lot trying to stay warm while I'm eating. Letting it idle probably for the better part of 45 minutes. Out of now where the Check Gauge light, 20 seconds later, big bang, white steam fills the air. I go to look at it and top of the radiator is split open, hose isn't bubbled or stretched in any way. Not sure where to start look as far as a cause. Could use some help.

It might help to note that it has a supercharger on it (not my idea, bought it that way, don't recommend). Which means the belt routing is different, not sure if that affects the fan or fan clutch at all or what it may do while idling. Thanks guys

 

[Apparition]

The plastic gives up and it happens. Mine did it on the trail.

You'll need a new radiator, preferably another factory one.

 

[sab]

Yup, that’s a common mode of failure for an old TJ radiator.

 

[Daniboyoh]

Yup, that’s a common mode of failure for an old TJ radiator.

I don't have the eye for it but is that a factory radiator? Potentially very old?

 

[L J]

Mines developed a crack along the top tank after a decade or so of service. I don't recall seeing one blowed up like yours, though.

 

[Daniboyoh]

Mines developed a crack along the top tank after a decade or so of service. I don't recall seeing one blowed up like yours, though.

It does run hotter than your average TJ from the blower. But I don't know if that equates to more consistent pressure build up in the radiator. To the point where it would pop vs just crack all the way.

 

[sab]

I don't have the eye for it but is that a factory radiator? Potentially very old?

I don't know from the picture if that is a stock radiator, but others on the forum might be able to. What I meant by my statement was that top tanks cracking is a common failure mode, and if it's old (your 2004 TJ is twenty years old, so it could be, if it's the original radiator), it could be fragile enough to grenade if the engine temps rose rapidly. Brittle plastic at high temps and a bit of pressure aren't a good combination. However, I wouldn't conclude that it's definitely the case with your situation. It's just a data point. One may assume that the radiator saw hundreds of psi (like from a blown head gasket) and exploded, but it may not be that dramatic. It could be that it got a bit hot and the brittle plastic gave up...

 

[srimes]

It does run hotter than your average TJ from the blower. But I don't know if that equates to more consistent pressure build up in the radiator. To the point where it would pop vs just crack all the way.

Shouldn't matter as you're sitting there idling. Presser is limited by the radiator cap. Might check to see that it's stock pressure rating and the gasket isn't stuck.

 

[BlueC]

Mines developed a crack along the top tank after a decade or so of service. I don't recall seeing one blowed up like yours, though.

I've had two plastic tank radiators fail, and they both went out like that, a simple crack and leak under pressure. An exploding tank makes me think there's another issue.

 

[Apparition]

I've had two plastic tank radiators fail, and they both went out like that, a simple crack and leak under pressure. An exploding tank makes me think there's another issue.

His is definitely worse than mine was but mine essentially blew up. We were idling on the trail and I walked to the back to grab a water out of the refrigerator and my entire engine got washed in antifreeze.

 

[JKP]

That's how they all fail. Get a new rad cap as well to ensure it's at the proper pressure.

 

[TonyArms]

i would bet the cap went bad and wasn't releasing pressure