Thread: Average engine temps

That’s fine. Remember it’s pressurised, so 115c isn’t ugly.

100 to 108 deg towing 2.8 tons at 35deg. Fan only kicks in over 100. If you have a GAP tool, you can watch the Viscous Fan Setpoint rise & fall as the cooling water temperature fluctuates.

You can leave the aircon on if you want to. They will turn it off and turn the heater on automatically if they need help to cool down.. I'm pretty sure 50/50 coolant with a 15psi cap boils at 130+ . It is great to be watching and aware of changes but.

Originally Posted by josh.huber

You can leave the aircon on if you want to. They will turn it off and turn the heater on automatically if they need help to cool down.. I'm pretty sure 50/50 coolant with a 15psi cap boils at 130+ . It is great to be watching and aware of changes but.

So true. Everyone uses 1960’s thinking with modern engineering. Engines today are far more efficient and are designed to run hotter to be more efficient etc. Anyhow, I give up

Originally Posted by DiscoJeffster

Engines today are far more efficient and are designed to run hotter to be more efficient etc.

Wot ‘e said. If the little white stick is not buried in the red and there is no bing, bong or warning on the dash then it’s all good. It’s a fine balance. The hotter it gets the more efficient.

Like most “modern” vehicles, the temp gauge is “compensated” which is another word for “reduced to an idiot light”. It’ll sit in the middle until things are a unholy temp, then it’ll peg to let you know things are not good. If it’s in the middle, you’re ok.

The only thing I do, is if it has spent an inordinate amount of time with the oil temp > 110C I’ll change it a bit early. But that’s probably me being stuck in the 70s. Modern oil is apparently better.

Sure, check the live data, but if the car isn’t reporting an overheat or low coolant, drive it like you stole it. The worst that’ll happen is it’ll do a crank, but that’s because it’s a discovery, not because it was working hard. In fact, most reports about cranks seem to be “I was cruising, or I was at the traffic lights”. Nobody says “I was caning the **** out of it and the crank let go”. Maybe giving it a bit of welly is a preventative. That’s my excuse officer.

Mineral oil (don't quote me) gives up is lubrication properties at around 130 degrees C. That's why we moved to synthetics especially in transmissions.. The main reason we run hotter is for diesel particulate emissions. Modern mineral oil still doesn't belong in a modern engine or transmission.
Modern coolants are a work of art in my opinion

The fan control is important for the ECM because they such massive amounts of power from the engine. So are only driven when required.

Originally Posted by josh.huber

Mineral oil (don't quote me) gives up is lubrication properties at around 130 degrees C. That's why we moved to synthetics especially in transmissions.. The main reason we run hotter is for diesel particulate emissions. Modern mineral oil still doesn't belong in a modern engine or transmission.
Modern coolants are a work of art in my opinion

Just remember that the grade of oil is specified at 100 degC(for engine oil). Typically once you start exceeding that temp the oil viscosity is going to continue to decrease. Not all oils will respond in the same way to increased temperature and the ability to resist changes to viscosity is known as the viscosity index. Typically synthetics have a higher viscosity index's than mineral, and can handle higher temps for longer before oxidising. But just keep in mind that most oils that are marketed as a synthetic are not really a true synthetic as you may think, they are most likely a class 3 base stock which is just a highly refined mineral oil. Mobil 1 is the only full POA synthetic that I've come across so far.

Back onto the engine coolant temps, my engine fan will really kick in around 117deg from memory - at least thats the point where you can hear it working