Coolant Temperature and Fan

[Donut]

Hello,

just made another mountain trip with my Mirage and logged the altitude and the engine coolant temperature on that trip, see graph below



The data shown is altitude and coolant temperature vs. time.

One can see that the engine coolant in the 90C until I start onto the first significant climb where it then rises up to 100C. Similarly, on the last stretch the coolant temperature oscillates between 90 and 97C. I had two grills blocked with a foam roll.

My question is whether I was already at the high limit of what the coolant temperature ought to be or how I could have optimized the grill block?

Would you have removed the blocks before the climb? I guess the fan had to come on to improve cooling and driving the temperature back to the 90C.

thx for your insights.

[inuvik]

Hello,

My question is whether I was already at the high limit of what the coolant temperature ought to be or how I could have optimized the grill block?

Would you have removed the blocks before the climb? I guess the fan had to come on to improve cooling and driving the temperature back to the 90C.

thx for your insights.

I've never been much of a advocate for grill blocking. Always seemed like a risky proposition to me. Since the 3A92 only has a 3 liter oil capacity and a small coolant capacity the risk of overheating far outweighs the benefit of any potential mileage gain at least for me.

[cyclopathic]

Don't block grill in summer! The only advantage of blocking is quicker warm up in winter, and perhaps in places with harsh winter like N Dakota or Alberta. Would be helpful if we had stop and go but it is not sold in US.

In MD you are looking at blocking from mid-November to end of March, and not more then 50% with gridlock driving good luck.

[inuvik]

Don't block grill in summer! The only advantage of blocking is quicker warm up in winter, and perhaps in places with harsh winter like N Dakota or Alberta. Would be helpful if we had stop and go but it is not sold in US.

In MD you are looking at blocking from mid-November to end of March, and not more then 50% with gridlock driving good luck.

I agree wholeheartedly. I've only partially blocked my grill during periods where the outside temperature will consistently be below zero Fahrenheit. Otherwise it's unnecessary and could allow your engine and if you have the CVT to overheat. Which is bad bad bad.

[Aphotog04987]

My question is whether I was already at the high limit of what the coolant temperature ought to be or how I could have optimized the grill block?

Looks like you've got adequate cooling at the moment, but you really need to see the results from an unmodified Mirage performing the same exercise. What we don't know is how much higher you're going (if any) than the stock setup. And unfortunately that's the important part.

edited: It also looks like the fan only came on in the last portion of the trip (the oscillation) so it looks like the Mirage takes altitude into account when pondering fan usage.

[deleted user]

Almost regardless of the airflow through the grille, the coolant fans will run more often if you block off too much airflow. With that kind of altitude variable in your drive, your concern should be can you block off so much of your grille that the fan can not keep up with your heat dispersion requirements.

The graph looks OK, but it will not show you the difference in fan run time total and whether it will or will not use more fuel due to excess fan operation and they probably are not designed for continuous duty (constantly running).

regards
mech

[Donut]

thx for your thoughts. I believe the fan came on a couple of times. At the end of the climb my mileage was dropping quite fast and went below the psychologically hurting 50 MPG. Next week, I'll head out for a really long road trip and I wanted to be sure, I'd be able to keep the temperature in the ok range. Will do mostly highway roads, I guess. At the moment, my conclusion would be to remove the foam blocks.

[cyclopathic]

Looking at your fuel log... very impressive!

[BillFieldz]

I was monitoring my engine coolest temperature before on my surface tablet whlie parked with the engine running and it seems when the temperatures reaches around 95 C the fan will kick in, trying to cool it down

[alex16]

Another thing to remember is that when your using A/C the system requires the fan to be on regardless of the engine coolant temperature.

As far as cooling systems go, not sure how good the Mirage's engine internal cooling system is but I know in some vehicles like my Jeeps 4.0L it is terrible, has to be working properly to cool efficiently. But in a car such as my 1991 Honda Prelude Si I had when I was 18, I was able to by pass the leaking radiator and cool the engine off the stock heater core in the middle of a Texas summer, (it was super hot inside the car though).