Excellent comments.I second them . Before adding an oil cooler, it is best
to know exactly what temp your oil is running. The best temps for
petroleum based oil are in the 180 to 210 degrees F. Cooler that that
causes excessive engine wear due to sudge and acid formation, hotter causes
the oil to break down and oxidize. Either one is very bad.
Regards,
Greg Solow
-----Original Message-----
From: William Zehring <zehrinwa@UMDNJ.EDU>
To: Art Hart <arthart@bell-labs.com>
Cc: morgans@autox.team.net <morgans@autox.team.net>
Date: Wednesday, February 03, 1999 10:49 AM
Subject: hot/cold
>At 12:27 PM 2/3/99 -0500, Art wrote:
>
>>I can't see why an engine would run any hotter with straight propylene
>>glycol than it would with a "normal" coolant provided you use an
>>appropriate thermostat. The advantage you would have is that when it
>>did get a little hotter than normal it wouldn't boil over, it would keep
>>on going and do a better job of cooling than a boiling liquid with it's
>>vapor pockets at the hot spots which need the most cooling.
>
>Okay, I'm no chemist, but be a little careful here. Just because one
>coolant boils at a higher temp than another does doesn't mean (to me) that
>it'll cool an engine better. You have to take into account the specific
>heat of the agent (the 'ease' (for lack of a better word) with which the
>coolant will take up heat (in the engine) and give it off again (in the
>radiator)). If it returns to the engine from the radiator not much cooler
>than it was when it left the engine, this isn't good. Its my understanding
>that straight ethylene glycol is inferior to a 50:50 mix with water in this
>regard. The glycol/water mix is better at heat transfer than is straight
>glycol, if also able to boil at a lower temp. Of course, Art is correct to
>say that a vapor pocket also seriously hinders heat transfer (minimally by
>blocking the flow/contact area of liquid coolant). The whole thing is to
>strike a balance/compromise between a given coolant's boiling point, its
>specific heat, and its freezing point (given a specific thermostat/radiator
>combo).
>
>I'd echo the remarks made by another list member with regard to NASCAR
>coolant formulations, race vrs. street engines, oil changes and rebuilds...
> IMHO, the straight ahead approach is a 50:50 glycol/water mix, a 160-180F
>thermostat, correct timing/fuel mix, and a re-cored radiator for any street
>car that tends to run 'hot.' Maybe an oil cooler...
>
>In the final analysis, I'm reminded of the remarks a jag mechanic made to
>me when I asked him if my old E-type (please, I wish I NEVER sold that
>car... except that it financed me Mog) was running too hot
>
>Me: "Is this car running too hot? It cruises at an indicated 190-200F!"
>Him: "Has it boiled over?"
>Me: "Nope"
>Him: "Then its not running too hot."
>
>my two cents worth, anyway...
>cheers,
>WZ
>
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