Have a Coke and a smile!

 

Da faq

 

You will see a 195* thermostat start to open at about that temperature. That is 17* before the boiling point at sea level.

The water is still clear at that point. Having it eventually reach a roiling boil is not necessary. As I said earlier, you cannot cause water to heat past its boiling point no matter how much heat you apply to it.

 

Wow! Name calling sounds like desperation on your part. Hope I didn't upset u......my bad.

I did't think we ever discussed "handling" a stat in boiling water......rather how u determine the "open" temp in boiling water. Will tongs determine the "open" temp.

I believe I post several posts earlier that one could determine the stat's open temp, how smooth the stat opened/closed and it's useful full open position without ever boiling water.

Also, I've never said boiling water would damage, hurt, harm in anyway, the stat......u, and others, have said that numerous times.

Turbine engines don't have some form of a central casting/forging (block) that all those components bolt to????

 

No. The have a shaft/axle and a housing.

In some circles, being called a blockhead can be quite the compliment. Like those who work on engine blocks all the time...

You are a bit sensitive, aren't you DJB?

 

Now be truthful.......u were paying me a complement........yah, right.

 

Blockhead is as blockhead does... Lighten up dude...

 

Does the 4.0 commonly operate at 210 (actual verified coolant temp) or is it verified by pretty much everybody who owns one that the 4.0 commonly operates with the dash gauge needle simply pointing to +/- the middle of the gauge? Which way is it? Would actual coolant temp be 210 when running the heater in cool/cold weather, and knowing that a 195 stat is essentially wide open at 210? U do agree that a wide open stat is doing nothing, don't u? U do agree that the factory dash temp gauge is simply an indicator with known inaccuracy, don't u?

Please elaborate on what it is that the t-stat "does not regulate"? The fact is, coolant is flowing the moment the motor starts so how does the stat "keep the coolant inside the block"?

Again, the XJ t-stat is not located in the block....it's not located in the long block.... it's located in the HEAD. If u want to help others, as u say, use the correct terminology. I mean, u did admit u were wrong about the stat being 190*, so maybe u could be wrong elsewhere as well. Man up, Dude.

 

You don't know what the thermostat is even there for, do you? It's whole entire purpose is to block coolant flow inthe engine block until the coolant in the engine block is hot enough to open the thermostat. When the thermostat opens, coolant is able to flow through the block. When it is closed, coolant does not flow through the block.

The purpose is to get the engine up to temp as quickly as possible.

I am going to start a census thread to ask folks what temp their 4.0s run at, so that you might come to understand your Jeep better.

 

https://www.cherokeeforum.com/f2/99-...erature-14995/

 

Coolant flows through the block, head and heater core any time the water pump is turning. The thermostat only blocks flow through the radiator.

 

Yep. That's what the bypass hose is for.

 

The thermostat regulates engine outlet temperature (to the radiator)
Coolant flows through the heater system at all times, regardless if the thermostat is open or closed. It also circulates from the head back to the block via this bypass at all times.

I am running a 195* thermostat.
When the engine is warmed up, and I'm driving in stop/go traffic in town, it runs around 205-210*.
When I'm on the highway, and it's cold outside, it runs somewhere around 175-180* (I'm sure once the coolant that circulates back toward the front of the engine heats back up to around 195-200* by the time it reaches the thermostat again) Probably why Jeep put the engine coolant temp sensor in the thermostat housing.
When I'm wheeling a trail, and crawling up a mountain, it runs somewhere around 225-230*
I don't worry at all at that temp because it never gets up near the red zone, and always comes back down once the electric fan has been on for a little while.

One thing that I'm confused about.
In the other thread that Crazy 8 posted. The OP mentions something about "all 99 are Reverse"
I'm not quite sure what that poster was referring to?
As far as I know, all 4.0 engines are cooled the same, minus the difference between the Renix, and HO overflow systems of course..........

 

Absolutely wrong.......coolant flow thru the block and head is never blocked by the stat.....coolant flows thru the motor the moment it is started.

 

Quote: "Coolant flows through the heater system at all times, regardless if the thermostat is open or closed""

Unless it is blocked from the heater core by a water control valve.