Jeep Wrangler TJ Cooling System Overhaul FAQ

Gonna be swapping off all of my autozone coolant products from my snowpolcalpyse break down last year and replacing them with genuine mopar parts pretty soon. Probably keep the radiator as a trail spare. I ended up using the green coolant and can say it does not look like its holding up very well. Still trying to fully understand how to flush everything on the other post!
 
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bobthetj03 said:
Thought I'd report here. After 20K miles, my O'Reilly's POS radiator has spring a leak at the bottom tank along the crimp. Do yourself a favor and take Chris's advise and get a Mopar unit. I'm not even going to try and attempt to warranty this piece of crap! Not worth the hassle.
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Take it out, warranty it, keep it as a trail/winter spare for someone in your club. Every year these cheap aftermarket radiators crack, at least buys someone some time to drive home from the trail or the side of the road.
 
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JamesAndTheSahara said:
Take it out, warranty it, keep it as a trail/winter spare for someone in your club. Every year these cheap aftermarket radiators crack, at least buys someone some time to drive home from the trail or the side of the road.
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Probably what I'll end up doing. Have to find the receipt.
 
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We are coming across more and more rigs that even after our normally sufficient 3 day drive flush from Prestone, the block still has rust and scale in it. 2 in particular have enough rust that they clogged the new Mopar Radiators. One has been flushed 3 times now and still has the rust and scale.

If anyone is aware of a better flush product that works better than normal, we need to find it. Or, if you are not sure of the condition of the block on the inside, pop the thermostat housing off and take a peek. If you are on the borderline of cooling well and not, do a flush first before you do anything else and keep at it until the block is clean.
 
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I've had really good results from Thermocure.

https://www.amazon.com/dp/B00R74I5UY/?tag=wranglerorg-20

Ran it for a week back and forth to work filled with distilled water and a bottle of this stuff and when I drained it I was frankly amazed at the improvement. My block was extremely rusty and the area under the thermostat looked pristine.
 
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fooey said:
I've had really good results from Thermocure.

https://www.amazon.com/dp/B00R74I5UY/?tag=wranglerorg-20

Ran it for a week back and forth to work filled with distilled water and a bottle of this stuff and when I drained it I was frankly amazed at the improvement. My block was extremely rusty and the area under the thermostat looked pristine.
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We actually use Evaporust and it works perfectly so I was considering using it in the cooling system but had a few doubts. Now I know I can get a specific product from them that I have no doubt will work.
 
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Man, I wish parts were more abundant on the weat coast for this repair. Damn near every heavy component is shipping from the east coast via Amazon. I snagged the last manual transmission radiator for the 6-cyl too apparently :0
 
jeep_boss said:
Man, I wish parts were more abundant on the weat coast for this repair. Damn near every heavy component is shipping from the east coast via Amazon. I snagged the last manual transmission radiator for the 6-cyl too apparently :0
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Yeah, most of it comes from the East Coast. Given how much your Jeep has issues, I'd probably try to order every single part you can think of in advance! :D
 
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Well I'll be damned! I was sold a bogus Mopar heater hose from an Amazon seller that runs under the guise of a Jeep dealership on the east coast. The hose just smells of a fake and what's worse, is it doesn't fit.. it is very loose unlike the other heater hose.

The rest of this overhaul was easy (thermostat, radiator, water pump), albeit for a few ridiculously placed bolts.
 
jeep_boss said:
Well I'll be damned! I was sold a bogus Mopar heater hose from an Amazon seller that runs under the guise of a Jeep dealership on the east coast. The hose just smells of a fake and what's worse, is it doesn't fit.. it is very loose unlike the other heater hose.

The rest of this overhaul was easy (thermostat, radiator, water pump), albeit for a few ridiculously placed bolts.
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Return that thing! That’s shady!
 
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I just finished my cooling system overhaul. I wound up doing the (195F) thermostat, water pump, radiator, fan clutch, and all hoses. Jeep is running at 201F vs. the 212-215 that it ran at prior!

It went well, but slow with this cold monsoon that hit Seattle. I did wind up wasting the extra FelPro thermostat housing gasket - started leaking coolant when I filled it - turned out the thermostat had slipped out and got pinched in the damned housing!!!

For anyone doing this overhaul — TAKE CARE to keep the thermostat flush!!! There is zero margin for errors.
 
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jeep_boss said:
I just finished my cooling system overhaul. I wound up doing the (195F) thermostat, water pump, radiator, fan clutch, and all hoses. Jeep is running at 201F vs. the 212-215 that it ran at prior!

It went well, but slow with this cold monsoon that hit Seattle. I did wind up wasting the extra FelPro thermostat housing gasket - started leaking coolant when I filled it - turned out the thermostat had slipped out and got pinched in the damned housing!!!

For anyone doing this overhaul — TAKE CARE to keep the thermostat flush!!! There is zero margin for errors.
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One less thing that will break on you hopefully! Well done!
 
ok so my jeep started running hot. i have the rad,water pump, thermostat and hoses as suggested. working on the factory clamps but what about the fan clutch and temp sensor . keep or ditch in the name of reliability?
 
59 wagon man said:
ok so my jeep started running hot. i have the rad,water pump, thermostat and hoses as suggested. working on the factory clamps but what about the fan clutch and temp sensor . keep or ditch in the name of reliability?
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If you can afford new OE Mopar ones, go for it! I should actually add those to the original post, it's a good idea to do them.
 
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59 wagon man said:
if you don't mind explaining i'm all ears
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Constant tension clamps have several advantages from the engineers point of view. They apply even pressure around the joint, where as worm gear clamps do not. Worm gear clamps pull from one side and this can stretch the hose, pulling it to the screw area. In smaller sizes, worm clamps leave a flat spot under the screw fitting; this leaves low pressure areas at the each end of the screw fitting. But most important worm gear clamps continue to apply pressure as the rubber of the hose dries out and shrinks over time making the joint last much longer without maintenance.

Corrosion can be in an issue for poorly coated constant tension clamps. Care must be taken to place a clamp back in the same place on an older hose. If not, it can leave a section with little or no pressure and lead to a leak.

@Jerry Bransford will back me up on this one.

In certain applications I think worm gear clamps are okay. However, for the cooling system, I'd use the constant tension clamps supplied by the factory, or aftermarket replacements if available.

I'm not saying that a worm gear clamp won't work, I'm just saying that I do hear stories about them causing leaks from time-to-time, that's all.
 
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