Yeah. Fan clutch seems good.

I'm thinking it has to be a clogged radiator that's not circulating well, or a bad water pump.

However, I read that if I have the high heat on and it is indeed blowing hot heat (very hot when temp gauge starts to go up past half point), that the water pump is circulating?

Is there any way to check if that port hole on the water pump has any pink sludge around it without taking too many things apart?

I'm going to take the skid plate off in the morning and have a better look.

Did you bleed/purge the cooling system of air after replacing the radiator cap and thermostat? OEM radiator cap?

Good news guys. I fixed it!

I'm not sure exactly what fixed it, but I did 3 things.

Replaced radiator cap, which alone did not fix it. However, the old cap did have a piece missing from the bottom. Whether or not this was preventing a good seal, I am not sure.

Secondly, I replaced the thermostat. While doing so, I drained the coolant out of the radiator. I refilled with 1 gallon of the Asian red stuff from advanced auto. This, too, did not fix it. At least not right away.

So then I figured maybe the 1 gallon wasn't enough to top off the radiator. So I bought another gallon and used about 3/4 of it to top the radiator to the very top. I'd drive a little bit, loosen the cap to burp it, drive a little bit, loosen cap to burp it, repeat while driving around my neighborhood.

While doing this I had heat full blast and turned off overdrive.

Now everything is running cool. As good as new. Needle is stuck just below halfway point.

I don't think I did any permanent damage because the 2-3 times it hit the red line I shut the engine down immediately.

I was so happy that I went ahead and replaced the power steering belt and AC belt.

Thank you to everyone who helped me. And thanks to the wealth of knowledge in this forum which helped me diagnose and go step by step trying the cheaper solutions first. And thank GOD I don't have to try to get in there and replace a water pump or something more serious and expensive.

Jiggle valve down, I hope? (opposite most all other engines)

The normal procedure for refilling most cooling systems is to fill as much as you can with the engine off, turn engine on and then keep filling as much as you can. A bit of revving, etc. will help get the bubbles out.

Expect to then have to do a couple warming and cooling cycles to get the rest of the bubbles out. The reservoir will drop a couple times during this time and need periodic refilling.

Some vehicles are a bit more involved or sensitive to filling procedure.

-Charlie

Yes. Jiggle valve down. Thanks to this forum I knew to do that.

Now that you mention it, I'll check the radiator a few times to see if I can get the rest of that jug in there now that it's cycled through a few times driving.

I also suspect that after 5+ years the antifreeze starts to lose some of its cooling properties. I'm not a chemist and don't entirely understand how it might break down over time, but that's my unproven theory at least. I'm in the hot humid south so the cooling system is working a lot because that thermostat is open a lot because it is hot as hell from April to October.

I don't have much in the reservoir, but should probably add some there to make sure air stays out of the system. In fact, that might have been how this entire problem all started. A large cut in the hose from the radiator to that overflow reservoir may have started to cause other problems.

glad you got your issue fixed
yep I would let it go through a few heat and cool cycles and keep checking each time to make sure air is out ( burped)
I think that part of the reason for this is we have some coolant ( heater) lines that are higher than the radiator, so air gets trapped.
Some people will park on ramps,( or curbs) so radiator is highest point and run up to temp
Or you can use something like the no spill radiator funnel kit (amazon etc). This too will give you a fluid level higher than the heater hoses.

I actually do both, ramps and the funnel thing