It runs like this most of the time unless it's on the highway. Then it drops to just below 5/8th. I know these Alphas are known to run hot, but this is crazy.
Is this normal at 100 degrees outside? Floors radiate massive heat as well.
I'm looking at a severe duty fan clutch, and just throwing on a 16" electric fan I have sitting around on a switch until I can get the dual fan setup copied from Reloader.
Thanks,
Matt
View attachment 30973
Hello there!
Talking from Spain but a lot of experience with H3 cooling system in both i5 and v8
First of all, yes, that is hot (not overheating) but hot. I read your last reply, if you are getting lower temps with a 16 inch pusher, definetly your clutch fan is failing. 16 inch pusher doesnt push enough air to cool down, so if you notice a difference, that is because your puller (clutch fan) is not good, so my list would be:
-Replace coolant (flush with distilled water and later add a 30% organic coolant if you live in a hot climate area, if not then 50% coolant.
-Add a bottle of Motul Moccol additive to coolant or Lucas Supercoolant (this will help a lot, most in heavy use situations)
-Replace thermostat. If you want to see 1/2 gauge that is 192-193 F. The best is a 180ºF thermostat (GM is 195ºF so choose another brand) or even better (is my application now) 174ºF LINGERFELTER thermostat.
-Change clutch fan, directly, i know is costly but more costly is to replace engine.
-Clean radiator completely, from outside and remove all the mud and dust of the fins. Is better to remove radiator from the Hummer and clean it out.
With these five steps you will recover 1/2 of gauge always. Remember to change water pump if your mileage is 100.000 miles or more since last replacement of the water pump.
A lot of people consider H3 stock cooling system capacity is not enough. That was not my experience, even in sahara desert, even at +100 F ambient temps. They are barely enough but if you open the restrictions (airflow and flow of coolant (lower temp thermostat) you can achieve great resuls.
A coolant that transfer better the heat will help also. Because water is the best heat transfer. The higher % of coolant, the worse the heat transfer. But you need a setup that could hold the freezing temps in winter. So I chose in Spain 30% coolant and a bottle of Motul Moccol.
If you have lot of accesories in the front reducing airflow, and healthy clutch fan, good coolant and additive, 174ºF thermostat and still getting hot under some circunstances, maybe good next move is a dual core radiator. But I am trying to avoid it in my alpha.
I am installing now a Camaro SS fan (850 watt brushless 19 inch efan producing more or less 5000 cfm) replacing the dual efans that replaced my stock clutch fan. I always want a efan setup for mpg and power, but in the alpha the ideal is the stock clutch fan (9000 to 12000 cfm engaged at high rpm). If I get a 1/2 gauge with Camaro SS and stock radiator even in Sahara desert under 100+ F ambient temps, that will be the proof that stock radiator could handle the cooling of the Alphas. I will report when I test the new setup
Best
Óscar Guerrero