I recently replaced the OEM Radiator with a 3 Core Reman'ed since I live in the Hot Desert of Manama, Bahrain here in the Persian Gulf deployed with the US Navy. Here is what has me curious.

Specs before Radiator Swap:

Average Temp in summer was: 210-220 degress

Specs after Radiator Swap:

Average Temp is: 110-120 degress and the weather has dropped substantially (About mid 60s to lower 70s currently)

Anyway, can't believe that the engines running 100 degrees cooler by replacing the radiator with a 3 core and having a 30 degree change in weather which has changed slowly.

Any thoughts?????????

where's it getting the reading at? If a radiator upgrade had that big of dif. there would be no over heating Jeeps. What thermostate did you put in, your engine (all) need to get to there optimom operating temp. to get the most out of them, you can go too cool!

Yea, Cutter's right. You can go too cool.

And if its running that cool, your too cool.

You want about 170-180 tops.

200 is about normal for a new TJ 4.0 Then once I clogg up my rad. with mud its about 215

MILKMAN, has a 96 XJ with a 4.0 and he swapped his rad to a 3 core and his temp is around 175 in the summer with the AC on.

He has a 185 thermostat.

Hope that helps ya.

Originally posted by Cutter
you can go too cool!

Exactly. most modern engines are designed to run pretty hot. Coolant boils at a much higher temperature in today's pressurized cooling systems. Keeping the engine running hotter allows better mileage and emissions.

My 258 YJ, my buddy's 258 YJ, and my other buddy's '91 YJ 4.0 H.O all run right around 210 - 215 year-round. (And that's in northern MN where the temperature ranges from -30 in the dead of winter to 100+ degrees in August.)

HTH,
Jake

My 94 4.0 YJ runs about 200 all day long no matter what, uphill downhill doesnt matter. Sounds like a thermostat that is stuck open or not in there at all.

210, always 210. at least that what mine keeps telling me.

210 with a 210 thermostat.... 180 with a 180 thermostat. from Chicago in the winter, to Houston in the summer.

that's 0 degrees to 100 degrees weather... and no fluctuation in operating temperature.

The 4.0 was made to run at 210. It runs best at 210

I always seem to run right around 210 as well. Summer or winter. Only when the radiator was clogged with mud have I seen it higher than 210