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Author Topic: 4104 Radiator Shutters  (Read 4152 times)
Stan
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« Reply #15 on: July 23, 2006, 12:36:37 PM »

Marc: My definition of setpoint is the temperature marked on the thermostat. I don't think any of your experts would recommend running a DD 2-stroke at 130* even though the system was at equilibrium.
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DD usually recommended a thermostat in the range of 180* or 185*. A fuel injected engine is a heat engine and the hotter you can run it, the more efficient it becomes. Unfortunately, there are many physical limitations to the operating temperature. Engineers select a compromise to give good fuel economy with long engine life. If you are interested in running engines hot, do some research on ebullition cooling which was the soup de jour about fifty years ago for stationary engines.

Thermostats were installed to maintain the engine within a very narrow temperature range. Once you exced the thermostat rating, you no longer have control of the temperature. In an engine with varying load (any motor vehicle) the temperature will be all over the place and never reach equilibrium.
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boogiethecat
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« Reply #16 on: July 23, 2006, 02:10:53 PM »

Bicker bicker bicker you guys... sheesh!!

Here's how the stupid things work, it's really simple.

Thermostats control the engine temperature by moderating water flow.  The system is only "in control" when the thermostat is somewhere between fully closed and fully opened... outside of those conditions it is no longer in control, and the engine may run too hot or too cold. 
  In REALLY cold weather, the amount of cooling a radiator can do is such that even with the thermostat closed, there is still more cooling going on in the radiator than heat generated by the engine and thus the engine can never get up to temperature.  Enter shutters, which throttle down the radiator's airflow, making that part of the system less efficient so that the engine can now heat up enough to get the thermostat back into the equation. To make their control simple, they are simply set up to stay shut until the engine reaches a temperature slightly below the temperature at which the thermostat begins to open. Then they open up and let the thermostat do it's job.
  On the other extreme, shutters and thermostat fully opened on a hot day, if the engine gets hotter than the thermostat is able to control, you need a more efficient cooling system, more airflow, bigger radiator or, oh my god, misters.

Marc- I'd love to see less deferring everything about cooling systems to what Bob Sheaves says/said/might say.  He may be great, he may know more than anyone regarding cooling systems, BUT consider maybe that's for him to tell us personally, and I don't see him piping up here, just a lot of reference from you about him.  I don't particularly like to keep hearing "but Joe said".... unless Joe says it himself....
And about engineers making more than educated guesses, I disagree.  I have found that, like many professions, actual degreed engineers are quite often some of the worst thinkers out there.  Bob may not come under that category, I don't know him... but In my 35 years of electromechanical design work I've found that the best thinkers are 100% the non-degreed guys, and the degreed engineers make a LOT of stupid mistakes that get all the way to production.  Recalls anyone? All brought to you by your friendly detroit designers.... (Oh.. case in point, if Freightliner's engineers had done everything "perfect" in the first place and not taken any "educated guesses"... why are they in need of hiring Bob Sheaves to do "upgrades" for them ?? Perhaps they're in need of some band-aids for inadaquate original "engineering"?   Hmmmmm, guess there's a BIG difference between all those test stands with millions of dollars worth of bells n whistles, and the real world...  Smiley  )

Bottom line,  back to the original post, Gus, you may still have some problems.  As Stan said, the shutters are not supposed to have anything directly to do with the actual engine temperature control... they are a secondary system that helps the thermostat do it's job when other parts of the system get so cold that the thermostat is no longer in control, because it's totally shut and can't get any "shut-er". (pun intended)
« Last Edit: July 23, 2006, 02:37:28 PM by boogiethecat » Logged

1962 Crown
San Diego, Ca
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« Reply #17 on: July 23, 2006, 09:28:31 PM »

Cooling systems are not sentient entities and therefore cannot be found to be stupid.

I dont' consider the exchange between Stan and myself to be bickering, more a search for common terminology. 

Thermostats do not control engine temperature, they only affect (you used the term "moderate") coolant flow in response to temperature.  The system as a whole, in conjunction with the operator "controls" the engine temperature.

You can be outside the temp range of the thermostat and achieve a stablized temperature.  The engine is only too hot when it exceeds the Mfg's maximum coolant temp.  For example 235 deg for a (some) S-60


As to your "On the other extreme"  you don't need a more efficient cooling system unless aeration is present, a condition you didn't specify.  What you actually need is a system with greater capacity.

Show me from the Bosch Design Guide, a common reference, where my quotes of Bob Sheaves are incorrect.  That was the reference used to prepare for the seminar.  Bob used to participate in the BB's but he tired of dealing with thoughtless criticism.  People didn't spend the time to consider what he said and spoke "from the hip" so to speak.

Freightliner's engineers probably did everything perfect,  except it was perfect for CONUS conditions, not Austrailia.  GVWR in excess of 280K pounds and ambient temps 10 deg higher than CONUS makes need for a much different (and larger) cooling system than the CONUS.  I raised these points earlier and you chose to "speak from the hip".   

Finally, your criticism of "degreed" engineers, states a minority but infers that the majority are so "afflicted".  I  agree that such individuals exist, but mayhaps you speak too generally. You should also consider the restraints placed on the engineer by the adminstration above him.  You speak from unstable ground unless you can establish that the engineer was given full latitude and support to complete his design.
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boogiethecat
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« Reply #18 on: July 24, 2006, 01:37:18 AM »

Oh Marc... get real and come to the real world dude.  You just love to argue don't you... about technical stuff, about politics, about almost everything.  I can see why others won't engage you.  From now on, me neither...and please remove me from your political mailing list....
Gary
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1962 Crown
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« Reply #19 on: July 24, 2006, 03:31:49 AM »

Gary,  From Wikipedia.  Searched on: "ad hominem argument"

Replying to an argument or assertion by attacking the person presenting the argument or assertion, rather than the argument itself  is (usually) a logical fallacy.

Instead of responding to the points I raised by citing their inaccuracy or pointing out the logic lapses (holes) in the points I raised, you attack the author (me) or his resource (Sheaves).

There are plenty of posts in the archives where I've apologized (even once to you, IIRC!)  when I had the facts wrong, misunderstood the issue, etc.

What's incorrect about the following point, seeking to clarify the use and meaning of the term efficient?

Closing shutters doesn't make the cooling system less efficient.  It reduces the amount of the air available to  carry away heat.   Efficiency deals with a qualitative factor when the shutters are a quantitative factor.  (Apples vs. Oranges time)

I asked you to supply facts in support of your position/argument and in response you urge me to "get real and come to the real world dude"

What's more "real world" than the facts?

Yes, I'm persistent, but only in response to either a persistant "ignorance" on how cooling systems work, or a persistant inability for me to explain basic fundamental aspects of cooling systems.

I'd wonder that you'd argue against the the theory of relativity by denying the point unless Einstein appeared in person and defended his theory.

I'm not running around like some huckster like Walker,  talking things up to gain some  personal advantage, or sell some product.  I strive for truth and accuracy.  I don't chortle and denigrate when I've made my point.  (No naner, naner, from me!)

If you really want to "make your point"  don't run and hide, tell me to "get real" or "take me off your list"  Tell me where I'm wrong and/or how I could say it better.

Isn't that what the BBs are for?




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Dallas
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« Reply #20 on: July 24, 2006, 04:30:55 AM »

OK guys,
This is as far as this needs to go.

This kind of arguing is not what the New MAK board is about and is not conducive to advancing the learning process and will not be tolerated.

If you have an opinion, that's good, but to try to force opinions on someone else is not the way to go about it.

I'm sure that Nick, Richard, Jack or myself do not want to be forced to take action here so lets try to keep it civil.

This is the first and only warning.

Thanks,
Dallas
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DrivingMissLazy
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« Reply #21 on: July 24, 2006, 04:52:24 AM »

Thanks Dallas, you just beat me to it. Course my plan was to delete the whold thing, but you did it better. Good (some) information saved for posterity.
Richard

OK guys,
This is as far as this needs to go.

This kind of arguing is not what the New MAK board is about and is not conducive to advancing the learning process and will not be tolerated.

If you have an opinion, that's good, but to try to force opinions on someone else is not the way to go about it.

I'm sure that Nick, Richard, Jack or myself do not want to be forced to take action here so lets try to keep it civil.

This is the first and only warning.

Thanks,
Dallas
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Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body. But rather to skid in sideways, chocolate in one hand, a good Reisling in the other, body thoroughly used up, totally worn out and screaming:  WOO HOO, what a ride
boogiethecat
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« Reply #22 on: July 24, 2006, 08:10:02 AM »

Thanks Dallas and Richard.  Totally agreed.
Cheers
Gary
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1962 Crown
San Diego, Ca
gus
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« Reply #23 on: July 25, 2006, 07:00:00 PM »

Well, I never expected to have my original post end up like this.

There is only one person I know that writes like Burgermeister and I thought he was gone!!

Oh well, one can hope.

Anyway, the bottom line is that my 4104 is maintaining the proper temps, at least for now, and I am happy. I don't really care what the theory for cooling is?
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PD4107-152
PD4104-1274
Ash Flat, AR
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