Thing is removing the t-stat, which increases flow to the radiator doesn't increase flow through the water pump or through the engine. If anything it could decrease the flow through the engine if the pump is weak. I'll be the first to admit I don't know it all, so how could that cause cavitation?

 

Looking at the construction of the thermostat I would bet that it's a pretty big restriction on water flow even when open. Removing it would probably increase flow and decrease the pressure in the water pump, so cavitation would be even less likely.

 

thook drilling a hole in a thermo doesn't affect the flow much at all. I have also done that to remedy the overshoot problem.


RustBucket you have to remember an engine is not a heat exchanger the radiator is. the longer the coolant stays in the engine the more it is gonna remove the heat from the metal. I agree the more the temp difference is the faster the heat transfer is. But the longer the coolant stays in radiator the cooler that coolant is gonna get. Would you rather give your engine a shot of coolant from the radiator with 190 degree coolant or 100 degree coolant? Oh wait there is that larger temp difference that was talked about earlier. Could this mean that if the coolant stays in the rad longer making the coolant cooler leading to a larger temp difference between the coolant and the engine that it will remove heat from it faster? I believe it does.

 

it doesn't. water pump rpm does (in addition to some other factors:see below) which is why I had said the analogy of the pump spinning slower was a bad one.

 

this is offset by the fact that the coolant (if the thermostat is not there) is cooler because it has not picked up as much heat from the engine. the hotter the coolant going into the pump, the better chance of it "boiling" when it reaches the suction side of the pump.

In addition to the higher rpm of the water pump leading to cavitation, it's because the suction side is gonna be a lower pressure and the exit side might be higher if not the same. (depending on health of the pump). the lower pressure causes the fluid to flash which is one of the many causes of cavitation of a pump this is called Hydrodynamic cavitation

 

I really wish I could borrow our work's Infrared Laser Thermometer so I can even prove to myself that my theory is correct.

 

I think I would rather a steady flow of warm coolant through the engine than have it hot on one side and cold on the other.

 

yes it can, the purpose of the thermostat apart from regulating temperature it also regulates the flow, with your holes it sounds as if your coolant is circulating too quickly at higher rpm's and not staying in the radiator long enough, samr thing happens when you take it out, thats why on racecars without thermostats some use a disc with a hole in the middle in place of the thermostat. you need something impeding the flow to some extent so the coolant is in the radiator long enough to radiate its heat.

 

That myth will never die, will it.

 

the only way I can see higher flow of water through a heat exchanger works is if it's. water to water. where you are increasing the flowrate of the cooling fluid and not the fluid being cooled. this is because you are keeping the differential temperature greater by introducing new cool fluid.

air to water would work as well as long as you use a higher flowing fan intruding a greater flow of air across the exchanger. but since the air temp would still be relatively the same, it's affects are not as high and a water to water.

 

If the flow is slower then while half of the system coolant is spending "enough time" in the radiator to get cool, the other half is spending too much time in the engine getting boiled.

 

1500+ degrees vs 190 or 100 I think isn't that much of a difference. Still extremely hot and still extremely "cold". I see where you went with that though. but that 190 will (numbers just for reference) bring that 1500 to say 1400 where the 100 might bring it to 1300.

 

who said our properly mixed coolant boils in the engine with the thermostat in there? come to think of it, this is where I would agree removing the thermostat would make the engine run cooler. but that would be band aiding the original problem of improperly mixed coolant.

 

I'm fully aware of that, but I was only addressing the actual title of the thread in contrast to the current topic of discussion.

 

heh nice hint, yeah we are a little off-topic I guess. I agree simply drilling that hole 4crawler suggests will not affect cooling capacity.