tempurature rising

[johnnyd125]

Hello,
I'm a newbie and I think this is going to be basic, but what do I know?
I've had my Grand Cherokee for two years and no problems. When I put my A.C. on my temp. rises almost instantly, it has gotten to 230 degrees and I never would check to see if it would continue rising (I'm sure it would). I checked my coolant, level and quality, and that's fine. My belts seem fine, although a friend grabbed the fan itself and didn't seem to think it should have any play in it, which it does. Grabbing a blade, it moved back and forth sideways as it goes to the big bolt it attaches to. It didn't look like anything abnormal to me. When I shut the A.C. off it's fine. This isn't a lot of play, just able to move it a bit. Any help is greatly appreciated.
JohnnyD

[JDPascal]

I would check for plugged fins on the condensor and rad.

Look for bugs and dirt build up - on the front of the condensor just behind the grill and between the condensor and rad. Also are the fins of the condensor bent over??

There is probably enough air moving thru the condensor/rad to cool the engine but with the extra heat from the condensor when the A/C is running, the air flow is to little.

If the condensor fins are bent over, you can get a fin comb from NAPA or other auto store to help straighten them.

Blow the bugs out of the fins with compressed air and then wash out the remainder with a garden hose.

That should help some anyway.

JD

[johnnyd125]

JD,
Thanks for the info, it did help some. I drove on a really hot day and and I could run the AC at medium fan speed, which was plenty good.

Thanks Again,
Johnnyd

[JDPascal]

any drop in coolant levels

Check back later. I'll re read your post and see if I can come up with anything else

JD

[JDPascal]

The movement in the fan is likely not contributing to the over heating - unless it is bad enough that the water pump seal is or the impeller inside the pump has come loose and is slipping on the shaft.

It could also be a rad that has slowly had the tubes plug with sediment and it is not transfering heat or circulating the coolant the way it should. A 2000 is pretty new for this to have happened but it depends on the water and cooling system maintenance done since new too.

Might be time to change the rad cap too. For the price its worth a try.

Running the A/C in the recirc position might help because there is not the heat load for the evaporator to deal with when recooling the air already in the cab.

If you can try some of these starting with cleaning and straightening the fins and washing them out. See what difference each step makes before moving on the the next.......

I'm running out of other ideas. I purposely didn't mention the thermostat because it runs cool enough when the ac isn't on.

Let us all know what improvments you get with any of the fixes you do try. Thanks.

JD