'99 Tahoe LT 5.7 running hot

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ol bessy

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hello all, and thanks for such a great place to learn stuff.

So my Tahoe is still running hotter than it should, around 220. It goes to about 230 before my new thermostat kicks in and brings it down. This is what I've done so far:

1. New HD clutch fan
2. New serp belt and tensioner
3. New rad cap
4. New Thermostat (old one had a destroyed o-ring)
5. New air filter
6. New coolant temp sensors (2 / both)
7. New coolant (50/50) not Dex-Cool though?

Notes:
-No leaking (coolant or oil) anywhere
-No water in the oil
-No warning lights illuminated
-I don't think I hear the new fan clutch "engage" but has great resistance. (is there a switch or sensor bad maybe?)
-Live in Utah where the temp has been 70 on average.
-A/C works fine and engine temp does not increase when in use.

Any suggestions would be great because I'm baffled.

Thanks again all, happy to have finally registered after learning so much from you guys/gals.
 

MO Viet Vet

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Two things. Remove the upper radiator cover plate that likely has the emissions sticker on it, look down in there between the back of the condenser and the front of the radiator. Clean out any debris from either the front or back of the condenser so you have good air flow. Compressed air works good. Plus, how do you know it is actually 220 degrees? The gauge may not be correct. Check actual heat reading at the thermostat housing with an infrared temp gun. You may actually be reading a lower temp and gauge is off.
 

ol bessy

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Thanks! I will do that in the morning.

In regards to the temp of 220, its just what the stock gauge is reading, plus or minus 5 degrees at most.

Took it to a radiator shop today, and they said my radiator was hot on top and cold on the bottom half. I've read numerous posts on that, and some say that's how it should be all the way to my radiator is clogged and just buy a new one, don't even attempt a flush it, and everything in between.
 

MO Viet Vet

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If in fact it is clogged it can have drastic readings difference from top to bottom like that. I would replace the radiator but still address the temp reading at the thermostat housing with a laser gun.
 

ol bessy

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So after all that work, it was a massive air bubble in the radiator. After bleeding it, it's right where it needs to be. Used my friends thermal and the guage is correct.
Thanks again for your suggestions and help. Much appreciated!
 
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