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Aspiring Perfectionist
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has anybody inquired why they鈥檙e operating temperatures are so high? Just curious because as you well know 204 and 206 is just below bowling point! It seems like they would thermostat them for 175+ or minus, I know there has to be a reason, I鈥檓 just wondering what that reason is 馃
Most gasoline engines operate optimally in the 190-210 range. The boiling point of 50/50 mix coolant under 15 psi of pressure is around 270掳F, so it's quite a ways below boiling point, even straight water boils around 250掳F in a 15 psi system.
 

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TLDR - When a system is under pressure it raises the boiling point of the liquid.
So yes, boiling point of water is 212f at sea level, but not inside your pressurized cooling system.

Atmospheric pressure of 14.7 pounds at sea level will allow water to boil at 212f and pure ethylene glycol will boil @ over 300f. This is one of the main components of coolant.
The most efficient compound for heat transfer is actually pure water, which is why we mix the coolant instead of running pure EG. This also raises the boiling point of the fluid and lowers the freezing point. Combine that 50% mix with 10lbs of pressure in your closed loop cooling system and your looking at effectively utilizing temps around 250f or so.
You should also note that there are many surfaces in the cooling system that are WAY over the boiling point of water, and the coolant would most definitely flash to steam if it was not under pressure. So this is another reason we pressurize the system, to avoid blowing it apart if the liquid is allowed to reach the flash point.

FYI I鈥檓 not sure what the rzr is running as far as pressure but these are just some figures to help you understand the concept. Of course being a union steamfitter I work with these basic principles for a living.
 

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Discussion Starter #64
I understand you have already replaced it, but you could

has anybody inquired why they鈥檙e operating temperatures are so high? Just curious because as you well know 204 and 206 is just below bowling point! It seems like they would thermostat them for 175+ or minus, I know there has to be a reason, I鈥檓 just wondering what that reason is 馃
People have said because of emissions
 

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Discussion Starter #65
So i just wanted to give everyone that helped an update because i hate when others don't. Anyway, i installed a new thermostat which wasn't too hard, one bolt was a bitch to get to, cleaned my radiator with a/c foam coil cleaner 3 times And installed a bypass switch for ther fan.

Today i took it out for a ride finally. The temp never exceeded 206. It would shortly climb and when it hit 206 it would drop down to 184-190.

To test the override switch, with the fan on, the temp stayed at 174-179.

So the comb of the thermostat replacement and cleaning the resistor thoroughly worked great and seems like my overheating issue is solved.

And if you are looking for a great waterproof toolbox for your xp1k, the ds400 by dewalt is awesome. Fits with minor trim. Pics attached
 

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Damn man how dirty was your radiator?? I pressure wash it after every ride. Glad to hear it was that easy though. Good work!
 
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