# Water vs air intercooler?



## 2ndWindfarm (Nov 11, 2014)

It's still cold here.. Minus 12 - but, Bluebird pretty! So, I'm still thinking about my seed and fertilizer order for this coming season and daydreaming about a different tractor to run my round baler.

Came across a listing that indicated the tractor engine had a "water to air" turbo intercooler. Always seen "air to air" intercooler. So, given that I only have an 8th grade education in diesel mechanics (or less).. What's the advantage/disadvantage of one type versus the other?

Appreciated perspectives. Thanks.


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## luke strawwalker (Jul 31, 2014)

There more compact, usually in the manifold. Not going to drop the air temp as much (since it's using operating temperature engine coolant to lower the air charge temperature vs. dumping the heat directly to the atmosphere) but they work.

Later! OL J R


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## Gearclash (Nov 25, 2010)

Both systems work fine. I tend to think that air-air is capable of pulling the charge air temp down more but as luke said air-liquid is more compact. I'm pretty sure air-liquid gets its coolant from the cooled side of the radiator, otherwise it would be ineffective. The assumption is that with typical boost pressures the charge air will be more than double ambient air temp after passing through the turbo, before any cooling. Some trivial terminology, an aftercooler is a charge air cooler located after all boost devices, an intercooler is located between two boost devices.


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## 2ndWindfarm (Nov 11, 2014)

My initial reaction was...how can that system be very efficient? My guess was as you stated - engine coolant pass thru radiator then thru intercooler to cool charge air. But, there's no way that engine water is gonna be cooler than ambient air.

I'm thinkin' it's "old school" technology but, the tractor is 2007-8! So, I thought I'd throw it out here and see what the real diesel jockey's had to say on it.

Went to the Nebraska tractor test site to see what the boost was for that tractor and it's only just 11.6psi to 14.6psi. So, I guess the intercooler doesn't have to all that super efficient, anyway.

Oh yeah, it was minus 18F here this morning! Really bright sunshine, blue skies - gorgeous!


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## SCtrailrider (May 1, 2016)

I can give some input here but truck wise, not tractor wise....

The intent is to cool the boosted air, the charge air gets heated due to the compression of the charge. In a diesel at 20-30psi boost that can be a good bit of heating, 200*+ over ambient temps, that's a bad thing, it increases cly pressures among other things.

With a WTA system it will only cool the charge air to engine water temps, say 200* for reference here, meaning the charge air is only being cooled 100* in the heat of the day.. or what ever temp your cooling system is running..

Now with a ATA system, the charge air will be cooled to near ambient temp depending on the system and location of the cooler itself and how clean the cooling stack is.. leading to much cooler air charge and their fore less cly pressures & MORE air at the same given boost numbers..

Another thing to consider is a WTA system there is a danger of a internal leak, that almost always leads to a hydro when the motor starts drinking water...

Just to qualify some of this, I have done a lot of r&r with the 6.5 diesels, much of this was in the CAC area so this is not just guessing on my part It's backed up..

I would think in AK the temps wouldn't be as high as they are here in the lower 48, so the cooler the air the better & more air the motor would get, ie less smoke, better performance, less chance of hydroing the motor....

I have build several HP 6.5's and would never have a water system unless it was a puller/drag type motor, just too many draw backs & dangers that go with that type system..

Just my 2cents worth...

Chris


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## 2ndWindfarm (Nov 11, 2014)

SCtrailrider said:


> Another thing to consider is a WTA system there is a danger of a internal leak, that almost always leads to a hydro when the motor starts drinking water...
> 
> Just to qualify some of this, I have done a lot of r&r with the 6.5 diesels, much of this was in the CAC area so this is not just guessing on my part It's backed up..
> 
> ...


That would definitely leave a bruise...

Appreciate the "schooling".


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## Gearclash (Nov 25, 2010)

I've never heard of an air-liquid cooler leaking-- but I could see the concern. For what its worth, Deere used air-liquid for many years on the 404 and 466. CIH used it as late as 2002 on the MX150/170, a Cummins 5.9 equivalent. CIH also used it on the 8.3 in some Magnum models.


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## mlappin (Jun 25, 2009)

Our MF8780 combine with a 8.3 Cummins is air to water after cooled, our MF9690 with an electronic 8.3 is air to air after cooled, the 8780's is much more compact, the 9690's makes 50-60 more HP. The 9690's is basically another whole radiator in a stack with the oil cooler and condenser.


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## SCtrailrider (May 1, 2016)

They both will do as they are designed, one is better at cooling the air charge, the other is more compact.. makers are limited with space and they do what they can with what they have. same in the auto industry, the 6.5 never came with a CAC, the dmax is ATA, ford & cummins I'm not sure with newer models but most are ATA not liquid... they each have a place and both are better than no charge cooler at all.... at least a charge cooler will be a filter so to speak when a turbo comes apart....


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## slowzuki (Mar 8, 2011)

The volume of the piping and big air to air exchanger can contribute to turbo lag as well if I remember right. Not really an issue in tractors.


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## 2ndWindfarm (Nov 11, 2014)

slowzuki said:


> The volume of the piping and big air to air exchanger can contribute to turbo lag as well if I remember right. Not really an issue in tractors.


Come on... I want the tractor wheels to jump on the end-rows when I start another bale!


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## SCtrailrider (May 1, 2016)

Just add another turbo and hold on


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## mlappin (Jun 25, 2009)

slowzuki said:


> The volume of the piping and big air to air exchanger can contribute to turbo lag as well if I remember right. Not really an issue in tractors.


Yep


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## cornshucker (Aug 22, 2011)

Mack Trucks even had a hybrid of the two in the early 70's to about 1980 it used water plus a tip turbine fan to blow air thru the small radiator that cooled the air. If you can remember the R and F model Macks that had two pipes coming out of the air filter canister this had it on it. They had a distinct whistle when under higher boost conditions most people thought was the turbo when in reality it was the tip turbine fan blowing air thru the intercooler. More efficient than the water jacket but more compact than true air to air. Look up ENDT-676 Mack engine to see a good picture of this.


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