I have looked, but somehow keep missing a sure way of getting the air out of my cooling system. I have searched the internet and forums and nothing they suggest works.. It has been a few years since I replaced my radiator, but I do remember I had the same problem then as I have now. I just forgot exactly how I fixed it. Seemed like it was taking one of the hoses off and filling it through the hose to prevent air being trapped. I just can't remember. I have tried raising the front of the vehicle and squeezing the top hose with the radiator cap off. The system does not burp! I even wore a big blister on my thumb squeezing the hose so much!

My gauge reads 3/4 the way to H. It used to read exactly at the half way mark. I know that someone must have had this same issue. Please help!

 

I can't figure that out that myself.

I purchased my 2008 h3 new, I replaced my original thermostat that always read 1/4 of the way up.
It now reads 1/2 when outside temp is around 80'. 3/4 if the outside temp is around 90'

I've been told the factory was never normal and my car is normal. I don't believe this to be true....

I'm thinking like you that i must have an air pocket somewhere. I'm thinking of getting a radiator flush from someone.

 

 

Did you replace the thermostat? after i changed my radiator and t-state my gage reads 1/2 to just under 3/4. You can drill a small hole 1/8'' or a bit smaller in the outer ring of the t-state and this will allow the coolant to pass threw at a slow rate while warming up. and help push any air threw, leave the cap off .
You can get a infrared temp gun from harbor fright for 20 or 25 bucks and check the true temp.

 

 

i did the rad and a year later the water pump in a 10,3.7. each time i refilled it,ran it,refilled and never had a problem. orig t stat??? filled the overflow... temp is same at just under half...

 

Thank! I forgot to mention I had my water pump replaced as well.

 

One more time, here we go. Temperature per the dash Temp gauge at 3/4 is COMPLETELY NORMAL FOR ALL I5 H3s & H3Ts.

There is no need to burp an H3 cooling system, there is no bleeder plug in the system and no independent drain for the system.

The correct fill procedure is super simple, fill the radiator to full, fill the overflow reservoir to the cold line, start the engine with the radiator cap off, let the engine reach operating temp (the coolant level in the radiator will lower when the T State opens up), add coolant to fill the radiator, put the cap on the radiator. Drive then let cool completely, check the reservoir and add coolant if not at the full when cold line. Drive more, check the reservoir level again to make sure it is still at the full when cold line after the system is at cold.

Always use 50/50 Dex-Cool and distilled water, or just buy it in the 50/50 premix.

The reason 3/4 is completely normal is the dash gauge is like an idiot light with a needle, not very accurate at all. When the needle points to Red, then you can worry, until then, the only way to see the actual coolant temp is with a scan gauge type OBDII reader. The H3/H3T have 3 levels of overheat protection which will be displayed in the DIC when occurring.... from a cut an past old post of mine on this beat to death repeat topic.

"First you will get an ENG HOT displayed, and if temp does not reduce, the PCM will shut down the AC if it is on and then you will see an AC OFF displayed with the ENG HOT, next if temp still does not reduce it will go into reduced power mode and.... REDUCED POWER will be displayed with the other messages which will definitely get your attention if you never even look at the dash.

When your H3 gauge is pointing at 1/2, the real temp of my H3 coolant could in fact be less than yours even with my gauge pointing at 3/4. There is probably a 100 old threads with people posting here that they think they are overheating, running too hot, because that dash gauge is at 3/4. Truth is, 3/4 is perfectly normal for many H3s. The old GM TSB regarding customers freaking out about a 3/4 temp gauge makes that abundantly clear, because the fix was.... scan the actual temp to make sure it was normal, and send them packing..... if they return complaining, replace the dash gauge with another one, check that and sending them packing. Zero work to the cooling system itself was suggested. Look in the owner's manual at the temp gauge, where is it pointing..... 3/4.

I can tell you that my dash gauge sits about 1/2 most of the time, the real temp is 193-195F. When it is hot and muggy, with the AC on, it might be at 3/4 after a while, the real temp is 206-210F, hottest temp I ever saw w/ gauge at 3/4 was 219F, no big deal."

 

My gauge always reads a bit under half even when it's hot outside, but it will read even a bit lower than that in the winter. It makes me think the engine it not getting hot enough. I used a scanner on it a couple of years ago and I remember it not getting up to the t-stat temp (maybe 10deg under?).