Aluminum Radiator

Approximately 9/11/03 12:08, Mike Romain uttered for posterity:

I'll be darned, you're right, woulda thought brass would be higher in thermal conductivity. However radiators are usually copper, which is almost as good as silver, not brass.

Diamond 1.28 Silver 0.968 Copper 0.928 Aluminum 0.520 Brass 0.338

Obviously, what you need for your winch/jeep is a diamond radiator.

I 'think' it is a 195 in most places, Bill commented something about

Just figure the hotter the t-stat, the more heat inside in the winter. :-)

Up in the Great White North. Mike

TJim wrote:

LOL!

So that is the second time you have mentioned copper rads???!!!

I don't believe I have ever seen a copper rad. All the ones I have repaired were brass or maybe bronze (brass and copper) but I sure can't think of any copper colored ones.

Mike

Good info to know. Thanks, Mike.

I used to see a lot of brass caps with brass tubes and copper fins but I don't think I've ever seen copper tubes, much less end caps and I haven't paid much attention lately but the las brass/brass radiator I repaired had brazed foil to the tubes,

For sure I have seen copper fins, but they radiate better than aluminum, so changing them is a down grade.

I was thinking the tank and tubes when I made my comment.

Mike

Diamond conducts heat well??? How about that! Well, it *is* carbon. I just never would have thought of diamond as a good heat conductor. Talk about an expensive radiator!

Approximately 9/11/03 17:12, TJim uttered for posterity:

Check with a computer chip geek, is used there for the excellent thermal conductivity.

It's lightweight, relatively inexpensive, easy to machine, weld, extrude, and form, and an especially good heat conductor, Josh.

Because weight savings are a good thing. The lighter your vehicle the less energy needed to move it, whether on flat roads, or stuck in (guffaw) deep mud!

Why, yes, Joshua, it certainly is. Its thermal conductivity is rather efficient. More so than steel. Do you have a piece of aluminum stock and a sander? Sand the aluminum and grind a hell of a lot of material off. Gets kind of hot in your hand, doesn't it?

Either that or, that's the reaction you get if you don't buy her one... ;-)

Joshua,

I guess I should quantify that. I don't have a computer controlled engine, so it isn't important that my coolant temp is in that range for emission control. Running an engine at 210 if you don't need to isn't wise, as the excessive heat plays a role in a number of possible mechanical failures such as belts, hoses, major engine gaskets and seals. In other words, it is best if you can run the engine as cool as possible, without going too low, which creates problems as well.

A cooling system that allows an engine to run in that range doesn't exactly have a direct effect on the above mentioned (possible) problems (except for maybe head gaskets), but the under hood temps that it creates does. This is why 210 makes me nervous.

True, but that is assuming that you are moving at a speed above a crawl. I come from the drag race and sprint car world where any temp that starts with a 2 is bad news. But, with the advent of computer controlled engines and emission laws, temp ranges in the low 2s are normal. The good news there is without a PCM controlling these engines, 210 would be certain death for them. 210 degrees, 10:1 compression ratio and 87 octane gas? Pretty cool actually. Without the PCM, that is a recipie for a roadside picnic.

I have a stock thermostat for my 98XJ that I just picked up yesterday.Chrysler Part Number 52028186-AB, its marked 195 to the side of the 'up' arrows :-)

Mike Romain wrote in news: snipped-for-privacy@sympatico.ca:

well - I have been trying to find out the coolant temp required for closed loop mode. I looked in the FSM & it only says "operating temperature" I tried Google.......& I found that the O2 sensor has to be 600F on a Toyota, but I do not see a specific coolant temp anywhere. If you run a cooler T-Stat, it may cause the JTEC to switch, back & forth, between open & closed loop.

A 195 degree thermostat is what's required for that year and model XJ, if that's the information you're after.

Jerry

Carlo, I'm not sure if I'm following who you're responding to but trust me, the factory specified temperature rating of the thermostat is 195 degrees, at least in all TJs. Absolutely. In fact, installing a 180 degree thermostat where a 195 degree thermostat is specified by the factory is a common cause of smog test failures. Absolutely. This is an area I'm well versed, this is no rumor.

Jerry

OK...........we agree. But does anybody know the actual temperature that the coolant must be at for the computer to go into closed loop???