Drove home from work, ran at 210 the entire way. This truck is possessed!

 

When the engine is stone cold, (off for 8-10 hours) it should require some effort to turn the fan by hand. It should not spin freely, it should stop immediately when you stop turning it.

At first start up, the fan should rotate at ~85% of water pump RPM and continue up to about 2500 engine RPM. During this time it is pulling maximum air through the radiator which produces a very noticeable "roar" sound. After the clutch warms up, it starts to slip and the fan almost free wheels when coolant in the radiator is at normal operating temperature, (~140F in the center of the radiator). The fan should be nearly silent, rotating at ~20% of water pump RPM. When the coolant in the radiator approaches ~200F, the clutch starts to engage and again pulling air, and roaring. When it cools, the clutch disengages and the fan quiets down.

Replacement is not difficult: Remove the upper fan shroud, unscrew the clutch from the water pump, transfer the fan, and install a new clutch. Buy Imperial Fan Clutch - Severe Duty 215158 at Advance Auto Parts

When the engine is at normal operating temperature, (200F) the lower hose should be noticeably cooler, (~130F) than the upper hose, (~200F).

 

Still sounds like it may need a coolant flush. Or failed water pump.

 

I always noticed at first startup the fan is really loud and I can feel the airflow under the car, that makes a lot of sense.

After letting it sit all night I could not spin the fan much by hand, if I tried to force it to spin it would stop almost immediately so it looks like the fan clutch is fine.

The lower hose is cool but I do not feel water in the hose, does it take a while for it to cycle through?

My local parts store didn't have the water outlet, going somewhere else today to find one.

I flushed the coolant a few times new, the first time a bunch of gunk came out for a few seconds then ran clear and has been running clear since. I filled it back up with coolant/water last night and it did overheat again today on the way into work.

 

Run it without a thermostat, see what happens

 

I think this may be the way to go for a few days, I will report back.

 

If it runs fine it was the t stat all the time. You know you can put em in upside down?

 

I pulled the t-stat last night and it was shut when I pulled it, I dropped it in boiling water and it would not open, so I think I had bad luck on this last parts run because the radiator cap I bought brand new last week was not even holding 1psi, it lost all pressure immediately.

New water outlet, radiator cap and thermostat installed last night, ran fine all night driving around but went up to 225 this morning for about 30-45 seconds before dropping back down to 210 the rest of the way into work.

 

Sounds like you got it, it will go over 210 at first till the cooler coolant flows through

 

My old thermostat would open at 195 so it never went over 210 until these problems started, I think this thermostat has a higher temp.