What is normal operating temperature?

[makenzie71]

‘97 540

Several months back I had a heater core hose popped...I was able to get the car shut down quickly and get the hose sorted, but I’ve let me paranoia take the reign since and have been watching the real time data stream off the dme. Once warmed up it pretty well camps out at 212f +/-3 degrees. I think one time while in traffic in early August, over the course of a 40 mile trip, I saw 221f. Briefly.

It’s pretty stable, but still seems a bit on the high side to me.

Can’t collaborate temps on the cluster...that gauge hasn’t gone past 11o’clock since I “fixed” the pixel stop...I’m about to send another cluster oand it to be fixed and converted to match the car.

[BimmerBreaker]

~105c

[geargrinder]

Google it. The MAP thermostat isn’t fixed and can go lower under load so there’s a chart. If yer not a forktard it comes right up with an appropriate google search terms. Otherwise yeah Graham is more or less right for basic normal hot op temp. A hunnert an’ change.

[makenzie71]

I’d read as much, but I do like to confirm what I see. Just seemed a touch on the high side to me.

[DennisG01]

Nothing wrong with 220*. The system is under pressure... which allows the temps to be higher than boiling... which allows your engine to be more efficient.

[Santaclaus4]

Just in case anyone was wondering, press and hold the "ALT" button and type 0176 for the ° symbol.
220° looks better than 220*.
Just adding my one quarter penny.
°F °C °K
Fahrenheit, Celsius, Kelvin.
It looks more like you slept at a Holiday Inn Express...

[BimmerBreaker]

Just in case anyone was wondering, press and hold the "ALT" button and type 0176 for the ° symbol.
220° looks better than 220*.
Just adding my one quarter penny.
°F °C °K
Fahrenheit, Celsius, Kelvin.
It looks more like you slept at a Holiday Inn Express...

What about those of us on cell phones lol

[makenzie71]

If I'm using my phone and really care about it I google "temperature symbol" and copy it :P. If you have an i-product the temp symbol is in the "123" menu...I'm sure my windows phone has one, too, but it's hidden behind some menu somewhere

[Santaclaus4]

My phone has the ° symbol in the numbers menu.

- - - Updated - - -

A co worker pointed it out to me years ago. I don't know how he figured it out but ever since, I try to spread the "word" on "°" when I get the chance. Lol...

[DennisG01]

Interesting tip on the "*"... but as you can see, "alt 0176" didn't work for me. Not sure why (1-year old Dell laptop). But appreciate the attempt at the tip, regardless.

[makenzie71]

It only works if you have a full keyboard with a number pad...depends on your laptop.

[DennisG01]

It only works if you have a full keyboard with a number pad...depends on your laptop.

Ah. No number pad on my laptop. Oh well, quite honestly... I'd probably still use the asterisk as it's quicker and pretty much everyone knows what we're talking about, anyways. Call it "forum shorthand". Considering how many strange abbreviations the kids have nowadays when texting on their phones, this one ain't so bad!

[Santaclaus4]

Ah. No number pad on my laptop. Oh well, quite honestly... I'd probably still use the asterisk as it's quicker and pretty much everyone knows what we're talking about, anyways. Call it "forum shorthand". Considering how many strange abbreviations the kids have nowadays when texting on their phones, this one ain't so bad!

That's how it starts... Next thing you know the English language is hardly recognizable. It's too hard... Lol
I'm not great at spelling and punctuation but at work I'm the guy people ask to look over their paperwork before they turn it in.

I guess it's just a matter of °. Hahahaha...

[geargrinder]

Yeah I usually do proper ° when I'm on the iDevices cuz its so easy (long press the zero), I used to have several symbol codes on a cheetsheet above my computer for the ALT thing - Euro, British Pound, Omega (for ohms) etc. - but guess I've gotten lazy, I normally just go 102F or 102C to indicate degreez. The * is a perfectly good quick cheat alternative for degrees IMO.

Another cheat is, If you're using a mouse, you can always just 'steal' one from someplace else i.e. copy-paste the weirdo characters from somebody/someplace else. That's a little more PITA using a touchytouch device... possible but a bit fussy, so its nice that its easier to get the offbeat characters on those devices using the advanced touch keyboard tricks.

[Luftpost]

Good info above, but a bit off subject.....

My 2000 540 has a 105 degree Celsius Thermostat in it. How do I know, because it is stamped on the thermostat and I looked at it last time I swapped out the water pump. I view my engine temps by unlocking the instrument cluster (Chapter 7, Page 1). The highest it goes is 110 degrees Celsius, but that's on a hot day. It normally runs around 96-97 degrees Celsius when ambient temps are 30-40 degrees Fahrenheit.

Hope this helps.

L

[computiNATEor]

Yeah I usually do proper ° when I'm on the iDevices cuz its so easy (long press the zero), I used to have several symbol codes on a cheetsheet above my computer for the ALT thing - Euro, British Pound, Omega (for ohms) etc. - but guess I've gotten lazy, I normally just go 102F or 102C to indicate degreez. The * is a perfectly good quick cheat alternative for degrees IMO.

Another cheat is, If you're using a mouse, you can always just 'steal' one from someplace else i.e. copy-paste the weirdo characters from somebody/someplace else. That's a little more PITA using a touchytouch device... possible but a bit fussy, so its nice that its easier to get the offbeat characters on those devices using the advanced touch keyboard tricks.

On a Mac, it's Option-0 (option zero). Easy. ºvº

[MotorMouth93]

Nothing wrong with 220*. The system is under pressure... which allows the temps to be higher than boiling... which allows your engine to be more efficient.

What's wrong with 220°F is that the pressure needed to keep coolant from boiling at that temperature is substantially higher than at a more normal operating temperature like 195°F. That high pressure and temperature is the main cause of 540i cooling woes, and the high temperature is partially to blame for the plastic timing chain guides failing prematurely as well.

I don't know about you, but I would happily trade negligible fuel economy improvements for longer cooling system and timing chain life.

[geargrinder]

Theoretically speaking the higher op temps are good for wear on metal parts inside the motor, which, in addition to emissions and efficiency (yes the primary factors), is why the engineers cooked up this "hot motor" approach. And the timing chain tensioner & U-guide were roller/idler based it'd all probably last 400k miles even at the temps. But they ain't, clearly.

However as menched, yeah, it is at the trade-off of much worse wear and tear on anything plastic and on the overall cooling system. I'm not all evangelical about making every M62 owner change the t-stat but it seems like a reasonably smart choice if & when you are doing t-stat and/or water pump anyway... Failing that, just leaving more air in your expansion tank seems to help a bit with holding off the rad + tank failures that's for sure.