Hi all,

Long-time reader, first time to post. Have an '08 base with the 3.7. I recently changed the thermostat with the AC Delco OEM replacement. I am well aware of the differential in temperature for the newer tstats at 195*, but wanted to run this by others as well

Upon refill, I added coolant radiator and to block through the intake hose. Heater core has maintained circulation since refill. Overflow canister has been refilled and I have attempted to purge by jacking the front end-up and also trying to burp on a ~ 45* incline with caps off.

Refilled with 1.25 ga of premixed dex cool at the time of replacement.

To date, I cannot get the tstat open. Lower hose remains cool to touch and no visible draw/circulation in radiator. The rig maintains temp gauging reading at about 1/2 - 5/8 with no real signs of overheating. Have driven numerous times down hwy and would assume that operating temp would have been reached by now.

I'm in Oklahoma with current ambient ranging from 30-50*.

Am I missing something, or is this typical with new replacement tstats? Trapped air between jacket and tstat, possible faulty stat from mfg. or rig temp remaining below operating temp? Have no easy access to scanner to test, thus looking for some direction in order to proceed. Assuming air, additional purging recommendations?

Thank you for your time.

John

 

if it didnt open the gage would go full scale and it would boil and blow up.
it reads 1/2 huh?
after new rad, still old stat mine reads as before, just under 1/2 but i read 180-185 on sg2 scanner, before it was 195. dont know why its not 195.
if you stay at 1/2 it must be working.

 

You are likely LOW on coolant, when you replace the T Stat you will need almost 2 full gallons. Fill the radiator until completely full. If you overflow it, use a turkey baster or something like that to suck out a wee bit so the cap will go in/on.

Another point, these systems are super simple, no need to purge anything. You fill the radiator to the top, fill the overflow tank to the line, drive it a few miles, check the overflow tank for level because if the radiator/block is low, it will draw from the tank. Add to the overflow tank if necessary.

Please check that level.

Oops, almost forgot, 1/2 to 5/8 on the gauge is normal. Get a scan gauge ant then you can read real temp. The dash gauge is basically an idiot light with a needle.

 

You say the lower rad hose remains cool. That is fine. Coolant still flows from top rad hose through the rad and into the lower rad hose. Just because the thermostat is attached to the lower rad hose does not mean coolant flows backwards. Very few vehicles have reverse flow radiators. Your lower hose is cool because the rad is doing its job. If the heater core has flow, which it does, and the coolant is full, which you say it is, temperature gauge is about half, which it is, just drive! If you are concerned, carry some coolant along with you for a drive. Generally if the top of the rad is hot the coolant is full. Zero degrees celsius here in Ontario Canada and the thermostat takes about 20minutes to open driving at 70km/H. Check the coolant a few times in the morning when cold and go.

 

where are you in OK?? I live in OKC, and I have replaced mine. if you have any questions send me a pm, and I am willing to help