Coolant Refill After Flush

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06DenaliXL

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I flushed out my cooling system today since its never been changed since 2006 (about to hit 150K). Reattached all the hoses, got about half a gallon of Dexcool in the reservoir to refill and I can't seem to get any more coolant in there. Reservoir is full and if I turn on the car, the coolant erupts from the reservoir puking out everything I just poured in there. Had the heater on full blast as well. What am I doing wrong here? I Know more than half a gallon came out when I emptied out the radiator. Temp is sky high, assuming because the radiator is low on coolant, but I can't get anymore coolant into it via the reservoir.
 

swathdiver

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I flushed out my cooling system today since its never been changed since 2006 (about to hit 150K). Reattached all the hoses, got about half a gallon of Dexcool in the reservoir to refill and I can't seem to get any more coolant in there. Reservoir is full and if I turn on the car, the coolant erupts from the reservoir puking out everything I just poured in there. Had the heater on full blast as well. What am I doing wrong here? I Know more than half a gallon came out when I emptied out the radiator. Temp is sky high, assuming because the radiator is low on coolant, but I can't get anymore coolant into it via the reservoir.

Thermostat get stuck?
 

OR VietVet

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How did you flush it? When you do flush you should always put a new stat in. Check the hose from the reservoir for blockage as well.
 

Joseph Garcia

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It seems like something is blocked. Perhaps, the thermostat, as Swathdiver suggested, or the reservoir hose itself, as PNW Vietvet suggested.

I recently had to add almost 4 gallons of coolant, due to a heater hose break, while driving on my 07. After replacing all coolant hoses and plastic 'Y' adapters, I was able to add well over 2 gallons to the reservoir, before it filled up. Then, I ran the motor for about 10 minutes, until it warmed up, and I saw the reservoir drain into the motor. Then I turned it off, and let it cool fully. Then, I was able to add another 1 gallon to the reservoir, until it filled up. Then, I repeated the process again for a third time, and I was able to add about 1/2 gallon to the reservoir, before it filled up.

Now, my reservoir is full to the designated mark, and it stays there.
 

iamdub

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Might be air locked. Give the lower rad hose a few good squeezes. You may even try pulling the upper rad hose from the water pump and filling the rad from there. Once you get the water pumping, it'll start purging the air.
 
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06DenaliXL

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I replaced the thermostat per the advice above. I've managed to get a gallon and a half in there, but looks like no more is going in via the reservoir. Turned on the truck hoping it would go down more,b but it hasn't. Both hoses are hot and lots of bubbles were coming out of the reservoir since I had the cap off. Temp is sky high at 245 per my Scangauge. I'll try pulling the upper radiator hose one it cools down.
 
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06DenaliXL

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Thanks for the help everyone, I managed to refill the cooling system by pulling the upper radiator hose from the radiator end, then pouring coolant down the hose until coolant started coming out of the upper radiator host port. Reinstalled hose, took it for a 30 minute test drive and test never went higher than 209, even with a few full throttle blasts. Definitely was a learning experience and not the quick fix I expected it to be.
 

iamdub

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Yup! Keep a close eye on that surge tank. If you let it run empty, then that's all air right back into your system and you'll be purging it again.
 
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