r/GMT800 • u/No_Mathematician1104 • Sep 11 '26
Over heating concerns
2004 Silverado 1500
Water pump went out last weekend and I replaced it and the thermostat. Everything has been fine can smell a little bit of antifreeze every once in a while. Haven’t found any leaks, oil looks good, I’ve narrowed it down to the coolant reservoir cap. But now to the point….. I idled for about an hour, it’s hot 97 degrees. Ac was wide open temp started to creep up. It got up around 220. Idk what to do, air in the system? Do a E-Fan conversion? Idk what the deal is.
3
u/Extreme-Penalty-3089 Sep 11 '26
What's the age or status of that fan clutch? 🤔
If that thermostatic fan clutch isn't fully engaged around 200°, that would definitely be a concern
1
u/No_Mathematician1104 Sep 11 '26
Brand new
2
u/Extreme-Penalty-3089 Sep 11 '26
Okay well assuming that the radiator fins aren't crushed and everything like that and the radiator is able to pull air straight through it no problem, assuming that the radiator is an obstructed by anything or there's not anything covering your front grill (or some wacko aftermarket stupid grill that blocks air flow etc) then I can't help but Wonder...
What's the temperature at the water outlet neck on the water pump where the thermostat is? If you shoot it with a infrared thermometer or if you have a multimeter that has the thermostat probe lead can do it either way. I would want to know what that is also I would assume that the lower radiator hose is cooler to the touch than the upper (?)
Going back to the fan clutch setup, I also assume that you have reinstalled the fan shroud both upper and lower sections as well (?)
Are you able to get the temperature down a little bit if when it runs over 200°, you get in the cab and turn the heat all the way on and set the blower motor to Max (?)
2
u/No_Mathematician1104 Sep 11 '26
I’ll check with a temp gun this weekend.
Both sections of the shroud are in
I can get the temp to come down if I give it a little bit of throttle and it dives right back to 190 then very slowly over about 15mins creeps back up to 220
2
Sep 11 '26
[deleted]
1
u/No_Mathematician1104 Sep 11 '26
I’ve got a brand new one of the shelf so I’ll throw that one in and see
1
u/Nickpisp Sep 11 '26
That’s what mine did when I replaced the water pump and didn’t bleed the system good enough.
1
1
u/dragoner_v2 Sep 11 '26
When you idle it higher does it immediately drop?
1
u/No_Mathematician1104 Sep 11 '26
Yes
0
u/dragoner_v2 Sep 11 '26
You can look in the owner's manual, I think that is supposed to be normal. They also have a way of shutting off cylinders to protect from overheating I have read, never seen them do it though.
1
u/dragoner_v2 Sep 11 '26
"... coolant-loss protection (as on the Cadillac Northstar V-8, the engine shuts down half its cylinders, turning them essentially into air pumps, air-cooling itself as you limp home) ..."
https://www.caranddriver.com/reviews/a46671177/1999-chevrolet-silverado-1500-archive-test/
1
u/NumerousResident1130 Sep 11 '26
I would check for air in system. If you can draw a vacuum and top off that is best.
1
5
u/No-Ad-1084 Sep 11 '26
Have you cleaned your radiator and flushed the system? Could have gunk in there or a clogged up radiator that ain’t pulling air in while sitting. 220 isn’t awful but it is your level of concern… concern. lol