Is the Tail wagging the Dog

[Gary Allan]

As far as airil? Go cheap! You've got gobbs of room to put as many as needed in line. It's not the preferred way to go from "something to admire for its ingenius and compact/novel approach" ..but who cares

For wateril exchangers. You see something like this on ebay

..and you buy every one of them that you can get your hands on. Add as many units as needed (one would probaby work).

I know you're looking for a packaged deal so you can have "one size fits all" application continuity ...

How many units are you dealing with anyway?? (did I miss this

)

 

[Steve S]

Probably the drivers over feuling, pushing the pedal to the metal instead of down shifting and easing up the hill.

 

[Killerbees]

Yes Steve, that is what is happening. Time is money for these folks.

The number of trucks that do this is probably in the thousands. I am working on modifying 20 right now. Still sourcing the cooler, the most challenging part, as most will not handle my 50,000 BTU/hr requirement. That is about the same heat rejection that a corvette uses at 55 mph.

Packaging is important also, I have to sell the appearance as a perfortmance option as well.

 

[1sttruck]

"The oil does not warm up ahead of coolant. It has the common characteristic curve of lagging the coolant. When under load, the oil pulls out in front by a large margin, as much as 80 degrees F. it appears as though, oil rise is pulling the coolant up."

If the drivers aren't keeping EGTs under the recommended maximum all you're doing is shortening engine life by making other systems look better. I'd make sure that the EGTs are controlled and then address any cooling problems.

You could experiment with the need for additional cooling by monitoring cooling system temps with the engine under load and then turning the heat on maximum, obviously with the AC off. I've had to do that in the older Taurus in summer when stuck in traffic to control engine temps.

 

[1sttruck]

http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/16137895/gotomsg/16139701.cfm

When I was driving from Vegas to pahrump, the temp guage started to rise then the hot fluid indicater showed on the information centre, tried to find some where to pull of the road but this took, a mile or so, by then the overheat engine indicator started to show on the information centre. then I lost all power and the engine shut down. By then of course, the engine started to boil over with the loss of fluid. I let it cool for about 10 mins, then put some water, back in and then got the truck started again. The engine fan soon called it down, and I drove on into Pahrump. Took it to the GM store there, and was told there was nothing they could do as they have about 8 in town that are doing the same thing. and most do it without towing. GM are aware of the problem, and they are working on it, but this is only happening on 05's. anyone else had this. the truck only has 3000 miles on it.

Do a search on "overheating." Several posts. Also, a member named Franklinman1999 has a similar problem. Look up his postings. Good Luck.

Go here http://www.dieselplace.com/forum/index.php and have a look. It has been around for a while and there has been a fair amount of work done to resolve the issue outside GM. Unfortunately, there doesn't seem to be a lot done inside GM about it. At least not yet.

Write to [email protected] and ask him for his stack sealing package. That should get the problem fixed. GM has also solved the problem from their viewpoint. They put out a completely redesigned front end on the '06's. No more overheating.

 

[Killerbees]

1stTruck

Was the links and quotes something I would likely not be familiar with? Were you aware that you were quoting my email address...? Just curious. Yes i have a thousand hours into the duramax thus far. "[email protected]", ring a bell? Just found it funny. There may not be anybody as familiar with it as I am from the thermal aspect, but I didn't realize I had become famous

.

BTW, IMO EGT is not the source of the issue, combustion temp is the best indicator of engine efficiency, the higher the better for purposes of reducing the heat rejection requirements per HP delivered to the ground. Materials limitations notwithstanding of course. EGT does give a measure of how much of the pistons work is left undone, with more of the diesel fuel's heat going down the tailpipe. Fortunately we don't have to reject that heat.

Our issue is rejection capacity.

Back to oil, I think I would like to access the oil, pre oem cooler. It would be 40 degrees hotter than what it sees in the oil filter. Anyone with enough familiarity that could suggest a way to tap into pressurized oil, before the oem cooler?

 

[1sttruck]

" "[email protected]", ring a bell?"

No, there is nothing in thread to suggest that it's your email. The thread that I posted suggested that you had a fix for the problem.

"BTW, IMO EGT is not the source of the issue, combustion temp is the best indicator of engine efficiency, the higher the better for purposes of reducing the heat rejection requirements per HP delivered to the ground. Materials limitations notwithstanding of course. EGT does give a measure of how much of the pistons work is left undone, with more of the diesel fuel's heat going down the tailpipe. Fortunately we don't have to reject that heat."

The higher the EGT the hotter the engine will get. With my diesel one may need to idle for a couple of minutes in order to cool the engine down, primary concerns being the turbo. Others have observed that the highest loads typically produce the highest EGTs, such as towing max loads up steeper grades at altitude, where even stock engines can start exceeding suggested limits. Extended idling cools it down too much, and an exhaust brake can help to increase engien temps in those situations. If you aren't measuring the EGTs you don't know what they are.

In any case you seem to be correct as the other thread suggests that nose changes fixed the problem ?

 

[Killerbees]

Do you have a duramax? What year?

The nose mods are an improvement to stack heat exchange, not by itself a capacity increase, just an efficiency increase of existing heat exchangers, maximizing the use of the vehicles kinetic energy (more airflow, there, that was easier to say)

The cooler is an attempt to find the best opportunity for additional heat exchange. Those that overheat, are around 90% of WOT. If I can add 10% capacity, then it should be near impossible to overheat.

The EGT discussion is hinged on thermodynamics of the diesel (otto) cycle. It is not by itself enough to say "lower EGT" as without it, the truck will go nowhere. Removing backpressure is the most effective way to lower EGT without a loss of power (increases power some). Other ways include better charge air cooling (expensive), cold air intake, even water injection(evaporative cooling). Hands down the best way to reduce EGT is to slow down. But that is not the scope of this project, performance is.

I have designed a unique cooler, now I need to see how well it performs next to the math. I may be able to squeak 80,000 BTU's out of it, if I can establish 15-20 gpm. Flow is a bit of an unknown with the d-max. If someone knows, chime in.

 

[1sttruck]

"Hands down the best way to reduce EGT is to slow down. But that is not the scope of this project, performance is."

I have a 2003 standard output Cummins, a CA engine at that, which is evidently their coolest running 3rd gen engine as they kept the combustion chamber temps low to reduce nitrogen compounds in the exhaust. It will probably do well in the most boring performance parameter of all, which is durability. People with EGT gages on those engines don't report problems with excessive temps under any condition. The most common recommedation for any performance upgrade is to first install an EGT gage.

 

[Killerbees]

If you compare the dodge front end with the GM, you can see the capacity differences, in the form of rad size, fan capacity, shrouding, heat exchanger layout.

04 and later emmission mandates are reversing the trends.

 

[Gary Allan]

I can see that you're basically trying to configure a package for the "Fast and Furious" crowd in the diesel arena. So this can't just be functional ..it has to have a certain "bling" factor to it as well ..just so the purchaser can marvel at its kewlness and take a little pride in the $XXX.XX (can we add a digit??) he/she shelled out for it.

Now the hard part. You've got to sell the notion that not only is this the best way to relieve their symptoms ...but that they deserve nothing less then this testimony to advanced technology (shhh..it's expensive). Anything else ..would not do them justices as professional drivers. ;^)

OTOH 12Ft (2X6')of cheap frame rail coolers would probably do the same job for about $200 per unit.

 

[Killerbees]

It's going to be expensive, I'm afraid, though not the desired end. Function remains to be tested on real loads.

This is for the guys who don't understand there is something other than WOT to get the job done. There are believers that think they should be able to use all the HP, for 15 minutes at a time, with steady state cooling capacity to match.

Not sure I quite understand the other references.

 

[Killerbees]

"Cheap frame rail coolers"

Can you tell what will reject 60,000 BTU's for $200, and not create 100 psi of back pressure?

The lines will be $200.

 

[Gary Allan]

I can surely be wrong ..but I think that your perceptions of pressure is a little overboard.

I don't have the skewling to calculate btu rejection rates and whatnot ..but I've observed plenty of flows across forced circulation heat exchangers and whatnot and I don't see it being a factor of major concern. You adapt as needed. I'd put two coolers in parallel ..use bigger lines ..whatever. Surely this would trump the need for some specially constructed piece that will face the exact same challenges at 10 times the cost.

These/this cooler is not going to deal with any fluid of substantial viscosity. It will be dealing with 100C plus since it will be thermostatically regulated.

I think you mean the lines will sell for over $200

btw- I'm obviously looking at it from a DYI/home grown perspective. If I was trying to package a marketable system ..sure ..it would require a little more thought and there would be a "packaging" factor that is involved in reasearching and developing something like this. Add a proprietary element to the cooler and the added costs get elevated substantially to the end user ..since there's also a "rate of return on investment" to deal with.

Sorry ..I'm a po boy

[ December 21, 2005, 09:52 PM: Message edited by: Gary Allan ]

 

[Killerbees]

I appreciate all the feedback.

 

[Killerbees]

HERE is what I came up with. Enjoy the reading

 

[Killerbees]

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