Novak Conversions Jeep Wrangler TJ radiator

Is this normal wear for a TJ cooling system?

TallGuy

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I've tackled my cooling system today. Radiator, water pump, stat and housing along with a temp sensor and serpentine belt. Did a massive flush over two days. 11 gallons of distilled water. Blue Devil radiator flush and even back flushed my heater core.

Looking at the housing and water pump does this look like normal wear on the hoses and these components?

Water Pump
Waterpump.jpg


Water Pump internal
WaterpumpInternal.jpg


Upper Rad hose internal
UpperRadHose.jpg


Thermostat housing
ThermostatHousing.jpg

I dropped the rad and flushed it with a hose and tons of gunk came out which was seemingly settled at the bottom. I did a shake and sloshed water a handful of times until it was clear. It was a rusty color.

The inside of the block was a rusty red and I'm wondering if something has gone wrong in the past to cause this.

My buddy thinks the TJ was possibly in a flood, but the VIN is clear and clean.
 
I've tackled my cooling system today. Radiator, water pump, stat and housing along with a temp sensor and serpentine belt. Did a massive flush over two days. 11 gallons of distilled water. Blue Devil radiator flush and even back flushed my heater core.

Looking at the housing and water pump does this look like normal wear on the hoses and these components?

Water Pump
View attachment 616156


Water Pump internal
View attachment 616157


Upper Rad hose internal
View attachment 616159


Thermostat housing
View attachment 616158

I dropped the rad and flushed it with a hose and tons of gunk came out which was seemingly settled at the bottom. I did a shake and sloshed water a handful of times until it was clear. It was a rusty color.

The inside of the block was a rusty red and I'm wondering if something has gone wrong in the past to cause this.

My buddy thinks the TJ was possibly in a flood, but the VIN is clear and clean.

A flood would not affect the inside of the cooling system. It looks like 20+ years of no cooling system care.
 
It looks like it's had terrible maintenance. Appears to have run mostly water in the system or incredibly weak coolant.

Probably you're right. I'm thinking this sat for many years as well. After flushing the system, the color started to clear up but it still remained a bit cloudy. I should have probably done another treatment but after flushing so many times and 5 hours of work on this thing yesterday, I was getting a little impatient. I'll do another round of flushing treatment after the summer I think. The temp is running good now and I have to move on to brakes. There about 2mm on the front. 😳


A flood would not affect the inside of the cooling system. It looks like 20+ years of no cooling system care.

Thanks for the insight. The PO must not have bothered much on maintenance. Shows how great these engines are tho. To keep going even with minimal care. Does make me sad tho. Haha


Typical for not having it flushed on a regular basis. My XJ had never had the coolant flushed/changed or the spark plugs changed when I bought it with 120,000 miles on it. Air filter box was full of acorns and the filter was black. I was happy that someone at least changed the oil. 😬

Wow, 120k and those plugs were probably begging for the grave! 😅
 
I converted my TJ over to Zerex G-05 years ago. It does not get the level of calcium buildup or rusting that you see when running cheap green "universal" antifreeze.

Nice that's what I'm using now. Most likely the PO went cheap here, and big on neglect. I'll stick with the G05 for sure.
 
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Piss poor maintenance for sure. I will use ONLY the MFG's recommended coolant, and change it at the recommended intervals. The "Prestone Green" stuff is fine for a 1963 GMC with all cast iron parts, but as soon as aluminum gets involved, I don't trust it. YMMV and all that.

I used the Prestone back flush kit on mine, FWIW...
 
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I've tackled my cooling system today. Radiator, water pump, stat and housing along with a temp sensor and serpentine belt. Did a massive flush over two days. 11 gallons of distilled water. Blue Devil radiator flush and even back flushed my heater core.

Looking at the housing and water pump does this look like normal wear on the hoses and these components?

Water Pump
View attachment 616156


Water Pump internal
View attachment 616157


Upper Rad hose internal
View attachment 616159


Thermostat housing
View attachment 616158

I dropped the rad and flushed it with a hose and tons of gunk came out which was seemingly settled at the bottom. I did a shake and sloshed water a handful of times until it was clear. It was a rusty color.

The inside of the block was a rusty red and I'm wondering if something has gone wrong in the past to cause this.

My buddy thinks the TJ was possibly in a flood, but the VIN is clear and clean.

My truck is like this. A Sears Auto Center ran dex-cool into my truck (which had green in it from the factory), and I suspect they didn't get all the green out. It ended up building up orange deposits all over the inside of the engine, like yours seems to have. It looks very similar, but more orange.

If I had to guess, I'd say lack of flushing/mixing colors did the trick. That or it wasn't 50/50 or richer and it simply corroded and built up.
 
Piss poor maintenance for sure. I will use ONLY the MFG's recommended coolant, and change it at the recommended intervals. The "Prestone Green" stuff is fine for a 1963 GMC with all cast iron parts, but as soon as aluminum gets involved, I don't trust it. YMMV and all that.

I used the Prestone back flush kit on mine, FWIW...

That argument doesn’t hold up, because before your specific coolant was specified, they recommended the green stuff and we still had aluminum water pumps and thermostat housings.

There is nothing wrong with the green stuff, but there absolutely is something wrong with not following proper service intervals.
 
That argument doesn’t hold up, because before your specific coolant was specified, they recommended the green stuff and we still had aluminum water pumps and thermostat housings.

There is nothing wrong with the green stuff, but there absolutely is something wrong with not following proper service intervals.

Ok, let's play:

Consulting my brand new 2006 owner's manual, it states QUITE clearly, and I quote: "Mopar Antifreeze/Engine Coolant 5 year/100,000 Mile Formula" right there on page 314. That is NOT the green crap.

It also states, on page 285, and again I quote: "Use ONLY the manufacturer's recommended antifreeze/coolant....". That does not constitute any endorsement whatsoever of the green stuff.

I've seen far too many vehicles with corroded or porous aluminum bits to ever use the green stuff on anything other than a full cast iron system. I *ALWAYS* use the stuff the MFG recommends - in fact I *ALWAYS* use the stuff that has the MFG's name on it, it just isn't that much more expensive even if you buy it from a dealer.

You do you, but I'll do me..
 
Ok, let's play:

Consulting my brand new 2006 owner's manual, it states QUITE clearly, and I quote: "Mopar Antifreeze/Engine Coolant 5 year/100,000 Mile Formula" right there on page 314. That is NOT the green crap.

It also states, on page 285, and again I quote: "Use ONLY the manufacturer's recommended antifreeze/coolant....". That does not constitute any endorsement whatsoever of the green stuff.

I've seen far too many vehicles with corroded or porous aluminum bits to ever use the green stuff on anything other than a full cast iron system. I *ALWAYS* use the stuff the MFG recommends - in fact I *ALWAYS* use the stuff that has the MFG's name on it, it just isn't that much more expensive even if you buy it from a dealer.

You do you, but I'll do me..

Did you read what I said? I didn’t say you should use green in yours. You mentioned not trusting to use green stuff when aluminum is present and I brought up the point that the manufacturer you’re taking advice from used to recommend green for the early TJs that still had aluminum parts in the cooling system (radiator, pump, thermostat housing).

And of course, the books always say to “ONLY” use whatever it is they recommend for that year. I’m not saying you should change what you use, I’m just saying the green stuff is perfectly fine with aluminum, as it was the recommended coolant for many years before your TJ, and it did just fine with aluminum then.

Despite me not recommending you to change it up, there is nothing inherently special to a 2000+ TJ calling for the Mopar HOAT coolant that makes it a requirement to use it. You could run green if you wanted. It is still the same old cast iron material in the block with an aluminum radiator, pump and thermostat housing. HOAT is a better/longer lasting/more environmentally friendly choice, but it isn’t the only coolant that will work. Green would also work just fine and you can even mix it. It just has a short life span. Although even most green sold now is rated to 150k/10y. I bet it’s more similar to HOAT than we realize. Still, not saying you should change anything. I’m mostly just emphasizing the fact that green and aluminum are fine.
 
Did you read what I said? I didn’t say you should use green in yours. You mentioned not trusting to use green stuff when aluminum is present and I brought up the point that the manufacturer you’re taking advice from used to recommend green for the early TJs that still had aluminum parts in the cooling system (radiator, pump, thermostat housing).

And of course, the books always say to “ONLY” use whatever it is they recommend for that year. I’m not saying you should change what you use, I’m just saying the green stuff is perfectly fine with aluminum, as it was the recommended coolant for many years before your TJ, and it did just fine with aluminum then.

Despite me not recommending you to change it up, there is nothing inherently special to a 2000+ TJ calling for the Mopar HOAT coolant that makes it a requirement to use it. You could run green if you wanted. It is still the same old cast iron material in the block with an aluminum radiator, pump and thermostat housing. HOAT is a better/longer lasting/more environmentally friendly choice, but it isn’t the only coolant that will work. Green would also work just fine and you can even mix it. It just has a short life span. Although even most green sold now is rated to 150k/10y. I bet it’s more similar to HOAT than we realize. Still, not saying you should change anything. I’m mostly just emphasizing the fact that green and aluminum are fine.

Ah but *IF* that's the case, then they stopped the recommendation of the green stuff. I wonder why... Could be that it doesn't do particularly well protecting aluminum? Hmmmmm....

Like I said, you do you. For me and my house, we serve the Goddess and we don't use green coolant! ;) ;) :D
 
Ah but *IF* that's the case, then they stopped the recommendation of the green stuff. I wonder why... Could be that it doesn't do particularly well protecting aluminum? Hmmmmm....

Like I said, you do you. For me and my house, we serve the Goddess and we don't use green coolant! ;) ;) :D

I’m sure they changed the recommendation to be more environmentally friendly, like everyone else has done over the years. The less often they recommend coolant changes, the happier daddy EPA is with them. Hence longer life coolants came about. It’s why everyone now uses a factory 10y-100k coolant. Not saying it’s a bad thing, but that doesn’t make the older coolants bad either. You just have to keep up with more frequent service on them.
 
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You can run about whatever standard coolant you want as long as you don't co-mix, and you regularly flush the system. If you want to run 100k between flushes (like I prefer), stick with the G05 and keep a backup jug in case you need a top-off.
 
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keep a backup jug in case you need a top-off.

If it’s just a top-off, water will work. Your cooling system will dissipate heat better with less than 50/50 mix - that mix is for freeze protection down to -30 degrees. It raises the boiling point only 15 degrees over straight water.

This is typically where I post the charts saved on my external hard drive, but I’m presently on an Apple device that doesn’t have USB ports like every other computer on the planet.
 
Novak Conversions Jeep Wrangler TJ radiator