Hope I dont annoy people with my 200 threads a day, but someone has to do it!

Anyone have a clue as to why? With the A/C off my temp cruising is 200*F if I turn the A/C on its 209-215*

I understand the compressor takes a load, but why would it effect the temp THAT much..

 

The way a/c works is this...it removes the heat form the cabin and uses the condenser to get rid of the heat.
the condenser needs air moving past it to get rid of the heat, the best place for it then?
Right in front of the radiator.
So all the heat being removed from the cabin is being dumped right in front of your radiator thus the higher engine temps with the a/c on.
A/c does not produce cold air, it cools the air by removing heat, your fridge, freezer, central a/c at your house all work the same way.

 

makes more sense now.

But is 12* really normal?

 

go out and feel the heat coming off your a/c unit at the house. 12 degrees is normal.

 

My truck runs at 196* w/o a/c on, 200* w/ a/c on.
All depends on the outside temp too, as well as elevation, how fast you're going, how loaded you are, the condition of your cooling system...but I would not worry about it to much.
I am assuming that your clutch fan is good.
The clutch fan should come on in the 210-215* range and then shut back off around 200*.

 

Not tryin to hi-jack, but this seemed relevant: I recently replaced my fan clutch and noticed if I run the a/c in city traffic at 85* ambient temp, my fan turns constantly. Normal? And yes, both electrics are working.

 

That sound normal to me kenk. I used to race chevys alot and only experienced the amount of heat from the chevy when I was runnung the car hard, as the amount of heat under the hood of my DII is always high while just normal driving. I ordered the parts last night to replace the factory thermostat with a aftermarket 170 degree thermo. Hopefully that should help me. I have a problem of all the rubber and plastics becoming brittle and breaking when touched. Just replaced spark plug wires with a set of Taylors high silicon wires. Hopefully they will last awhile.

 

Absolutely, as the rejected heat from your condensor is coming thru' your rad and heating the fan clutch.

luck,greg

 

The stock stat is 195. Unless you find a way to bypass the ECU, your truck is going to constantly run cold at 170 and stay in open loop. You will overfuel all of the time. Running a colder stat will not help you with anything.

 

O.k., guess I wont worry then. I was just used to my old fan clutch that never engaged except at first start of the day.