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Diesel Coolant Temp

Plongson

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Have you noticed the running coolant temp of the new JL 3.0 diesel? 205°f-225°f
I know that is not excessive, but I'm use to all my diesels (Cummins and John Deere tractors etc) running no more than 190°f. I suspect it is all to meet emission standards and keep the DPF nice and warm, but it sure would have been nice to have a cool running diesel engine...Oh well, it is what it is...

JFYI...I got stuck in a rollover accident traffic jam on the 95 North in Las Vegas for one hour the other day when the ambient was 105°f, and the coolant sat very comfortable at 205°f with the AC going the whole time.
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WXman

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Every diesel I've ever seen has run above 200F because it's a necessity. Compression ignition relies on heat. There are no spark plugs. Gotta' generate heat to properly burn the fuel.
 

Fredski007

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Have you noticed the running coolant temp of the new JL 3.0 diesel? 205°f-225°f
I know that is not excessive, but I'm use to all my diesels (Cummins and John Deere tractors etc) running no more than 190°f. I suspect it is all to meet emission standards and keep the DPF nice and warm, but it sure would have been nice to have a cool running diesel engine...Oh well, it is what it is...

JFYI...I got stuck in a rollover accident traffic jam on the 95 North in Las Vegas for one hour the other day when the ambient was 105°f, and the coolant sat very comfortable at 205°f with the AC going the whole time.
Ran several trails in Moab yesterday, 4 low and just crawled over most stuff, never went over 207, drove for hours!

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JLDIESEL

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Any updates on what the norm is? I am especially interested in those with bigger tires. I see 210-220 as the norm and crept up pretty high today in 110 degree weather
 

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AZ-Chris

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I’m seeing 212 degrees after running 85 mph for a couple of hours on I-90 crossing SD & WY
 

Gorilla57

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I know mine is a Ram with the 3.0, but hit 225deg coming home from Flagstaff. I was going up the hill out of Camp Verde and having to get on it a bit to get around slower traffic. At the top of the hill is when I hit that number, but temps dropped rapidly after we started going down the back side.
 

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I hit 239 degrees pulling a travel trailer from Pueblo over to Gunnison. I was watching the transmission temp--that's not a problem. It's disappointing because the Jeep engine could pull a 3000# trailer over those passes at 65 mph no problem, but the coolant system can't handle it. I backed off to 40-45 mph up the passes and turned off the AC and the temp stayed around 217.
 

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Plongson

Plongson

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The issue seems wide spread and not limited to just a few units...Makes me wonder if it's designed into the emission control or if they are really not able to cool themselves down...if that's the case, there might be a recall for engine temp.

Like I said earlier, all my Cummins and John Deere engines run at 180°f and never pull more than 190°f. These little motors are running way too warm IMO.
 

Sydwaiz

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I've been doing a little reading while waiting for mine to arrive and it appears that the Ecodiesel uses a water cooled turbo charger. I'm willing to bet dollars to doughnuts that this directly affects the coolant temps especially under high boost where the turbo is generating the most heat.
 

Compression-Ignition

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Well someone needs to find a thermostat with a lower opening threshold and install it. I'm wondering if the whole system will freak out trying to compensate? Just seems crazy that these things were most likely designed to run this hot for emissions purposes, yet it might be detrimental to engine longevity running so hot.

I also want to know if these temps that have everyone worried are actually dangerous? I know conventional wisdom says yes, but a few things have changed over the years. Who's got an FCA engineer buddy that we can pump for information?
 
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Plongson

Plongson

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If you watch the digital offroad gauge, it changes VERY fast depending on load. It will go from 225°f to say 205°f in just a few seconds and if you pull over it drops like a rock...unusual to say the least for coolant temp to change that fast. Now if you watch the analog gauge on the dash, it never changes, it's very steady and does not arouse any worries.

Conventional wisdom says they should use the same sender, but who knows.

Bottom line, if these engines are really getting this warm and enough people bitch (and there are failures...) we might see a recall. Too bad some member with a radiator shop can't make an oversize radiator and see if it controls the temp better.

These suckers just run too dang hot for my liking...I saw 230°f today running the AC pulling a grade empty with 100°f ambient. It didn't come down until I backed off and threw less fuel at it. Very curious indeed.
 
 



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