LLY: Why am I STILL running to hot?
- Thread starter TRUBBS
- Start date
Not trying to start a conflict, but facts are facts. I had a high degree of fan engagement when I purchased my truck. Installed Engineer837 AUX radiator (Larger Capacity than the V2) I've also completed most if not all recommended mods to help the LLY stay cool. I haven't heard the roar of the fan since....at most a mild fan engagement when pulling long grades towing in 100 + temps. I'm not running an oil temp guage, but if I had high oil temps I'm sure I would see issues when I have the oil tested at Blackstone each year....
There is a whole lot more to cooling your engine/engine systems, than just adding more coolant capacity. Sit down class.
Oil(engine coolant)has over 2x the heat retention of the radiator coolant. 2x. So as long as the super hot engine oil is passing over the internal stack plate oil cooler, that is in turn being cooled by the radiator, your engine oil will always be gradually heating your coolant, because the rad coolant does not have the thermal potential to pull the heat the oil absorbs from the engine, away from the oil. So by adding more coolant, really all you are doing is PROLONGING THE TIME IT WILL TAKE TO OVERHEAT, and while that may be O.K for some, it is still not adressing the true issues and is just a bandaid to a poor design.
Oil(engine coolant)has over 2x the heat retention of the radiator coolant. 2x. So as long as the super hot engine oil is passing over the internal stack plate oil cooler, that is in turn being cooled by the radiator, your engine oil will always be gradually heating your coolant, because the rad coolant does not have the thermal potential to pull the heat the oil absorbs from the engine, away from the oil. So by adding more coolant, really all you are doing is PROLONGING THE TIME IT WILL TAKE TO OVERHEAT, and while that may be O.K for some, it is still not adressing the true issues and is just a bandaid to a poor design.
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Looks like I need to seal my air box and get a lid on it,
Wrap the intake pipe & cold side cac pipe.
Build an oil cooler
Build aux coolant cooler.
Keep the comments coming guys, anything here helps. Might help someone else who thought that they took care of everything needed to keep a LILLY cool...
Wrap the intake pipe & cold side cac pipe.
Build an oil cooler
Build aux coolant cooler.
Keep the comments coming guys, anything here helps. Might help someone else who thought that they took care of everything needed to keep a LILLY cool...
Mine were on multiple trucks.
I even lost a fan clutch once and will still able to go on.The radiator cools the oil.
This has been proven several times over. Keep the water temps down and everything else is fine.I want a new teacher!:roflmao:
Maybe one that was at the forefront of the problem back in 2004.
Also most of those other mods were tried already and had no real effect on the problem, even when used all at the same time.
......or you could get an lbz.... lbz's are the best
I have spent countless months just thinking about how bad ass lbz's are. Many top scientist already proved my theory.
lbz's are the best I have spent countless months just thinking about how bad ass lbz's are. Many top scientist already proved my theory.
Has anyone really figured out exactly why some LLY's overheat? I've had two LB7's and now an LBZ and never seen over 210*. I just recently pulled a heavy load and the outside temp was 106, my trans temp got up higher than normal but my coolant temp stayed about the same as always.
......or you could get an lbz....
I have spent countless months just thinking about how bad ass lbz's are. Many top scientist already proved my theory.
Wana sponsor me one? Lol
The radiator cools the oil.
I want a new teacher!:roflmao:
Maybe one that was at the forefront of the problem back in 2004.
Hmm. Well like i said some are ok with adding more coolant to "solve" the problem. Science is pretty straight forward on thermal dynamics of fluid, and on the thermal exchange between air and fluid coolants passing through heat exchangers. Built properly, an external engine oil cooler, run with the internal stack plate cooler, still being in contact with the radiator coolant, can actually cool your coolant in the radiator. The engime oil cooler needs to have roughly 120,000 btu/hr of heat exchange potential, that is about a 4" thick core 9" tall and 28-30" long. I forget how many rows n stuff. The knowledge required to understand this principle was written long before 2004. Thanks for the super info though rick! you are telling me adding extra coolant will lower your oil temps.....
Must be a hit or miss thing with LLY's. Mines on 38's, had 10-15k behind it many times and even in vegas 100*+ temps, coolant never climbed past 210....thats read off the Edge CTS screen.
Ya know there was not a worse addition to the duramax than the egr cooler and egr system(imo) unfortunately the LLY was the egr systems guinea pig, if there was one single thing i would tell LLY owners to try, it would be to remove the egr, along with add a sealed cai and exhaust, and maybe a lbz/better water pump, trans cooler and external engine oil cooler, then the kitchen sink
The radiator cools the oil.
I want a new teacher!:roflmao:
Maybe one that was at the forefront of the problem back in 2004.
Do you also support the theroy of if the coolant were to stay in the radiator longer, the system would run cooler? Thats about how smart you sound to me, with your last post there.
This subjects been beat to death by people far more involved and with more time invested than you'll ever know. If you don't believe it, quit insulting prople here and spend a month on DP reading about LLY overheat issues..... its a sore subject for some but there's an assload of info there about what works and what doesn't.
My experience in the matter goes back to construction equipment and dump trucks. Alot of what i learned there/then applies here/now. I dont know about the LLY overheating issues in depth, each experience in used vehicles is different, due to the quality/level of involvment of the owner. I already said adding more coolant capacity will help or even "work" for all intents and purposes, but still is not solving a problem, and oil temps are still going to be reletively high. Oil holds more heat than water/coolant. Pure and simple. If you can keep the oil cooler on it own the coolant in the radiator has less heat to absorb, period.
That was insulting, sorry rick. really i was just trying to state that our opinions on the matter could not be further apart, we are like from east to west. If the manufacturer was not so damned cheap we would all have an external oil cooler, but they build theese things to make money, its up to us to understand how they built em wrong, fix em and get them to last forever, while having fun to boot. In my quest to make my rig last longer i will employ an external oil cooler, long before a larger radiator. But i also own an lbz so my direction will be different than an lly owner. When i see people sayin all you need to do is add a bigger radiator to run cooler it pisses me off cuz its misleading. I would bet 99% of dmax owners dont know the temp of thier oil. If they saw it they would chit. I just figured the manufacturer had it covered. They dont, all they care about is that it is there. They dont want your truck to last forever either