Ive got a 2007 with a 4.7, around 103k miles. My fan clutch went, which destroyed my water pump (see picture), I have done another cooling system flush as of yesterday, replaced the water pump, thermostat(again), replaced the fan clutch and burped the system for almost a hour. It isn't a head gasket issue, i'm right around 160psi on all cylinders, the radiator is flowing properly hot on the top cold on the bottom. With the ac off it rides around 11 o'clock on the gauge, but the minute i turn the ac on it tips over the centerline and fluctuates around the 1 to 2 o'clock. Turn the ac off, its back to normal temp, the ac clutch is making a odd noise but it's been doing that since i bought the truck. I can put it to the floor and the temp never moves. I dont understand how the ac is causing this issue, I was thinking their might still be pump pieces blocking the cooling passages, but I would think that would cause it to constantly overheat. Any insight would be appreciated.

 

That is a mystery. The A/C doesn't get its cooling through the cooling system - it has a separate condenser and fan.

Do you have a way to confirm the water temp goes up? A scan gauge or some code readers will provide water temp readings.

 

I'll hook my cortex up to it, I didnt think about using the data logger on it.

 

Is your electric fan coming on with ac activation ? It should.

 

My condenser fan went out a few months back and I replaced it with a 10 inch flex-a-lite, but it's working fine.

 

I spent the last 20 minutes driving like a idiot with the ac on high and it stayed around 210* according to my tuner. I'd assume that's about where it's suppose to be.

 

What is the thermostat temp? 190? 210 would be normal.

 

It's a 195, I can't seem to find anything lower than that.

 

195 means that is when your stat is supposed to open. It doesn't mean the water temp is going to be or stay at 195.

210 is normal

I run a 180 stat and usually my temps are 188-190