What exactly is normal "operating temperature"?

[Formerly Steve Wilkinson]

Let's admit it, these special-purpose, semi-exotic, relatively pure sports cars have gotten into the hands of a lot of people who understandably are going, "Why is it so different than my Acura/Lexus/Mercedes/whatever?"

After all, there are a lot of 911 owners who still believe they are driving "an air-cooled car." It's not air-cooled and it's not "a car."

[Joe Bob]

Have you checked the temps with a pyrometer to see if your gauge is accurate? Or maybe the thermostat is opening to early....

[DanielDudley]

Originally Posted by mikez

Have you checked the temps with a pyrometer to see if your gauge is accurate? Or maybe the thermostat is opening to early....

Smart.

[Joe Bob]

I try....BTDT.

[mickey356]

Sorry Iceman, I did skim over your post, my bad.

In regard to these "cars"; Hey, we all gotta learn, right? There's obviously been enough idiots like me over the years driving these and many have survived our torturous treatment. I guess that says alot for the engineering and durability of these "cars".
My hopes are that I will find a way to drive my car year round (I live in the Mid Atlantic area and it doesn't get brutally cold except on occasion) but if I have to hang it up for a couple months of the year to keep from doing it damage then so be it. I knew when I bought my car that I wasn't buying a "car car", but I also thought it was something I could drive year round. I guess we all live and learn. Next time I guess I'll get a Lexus or move to Florida so I can drive year round.

I'll swing by my buddies garage and see if he has something we can check the accuracy of the gauge with. Thanks for th heads up.

[911pcars]

If gauge and sending unit check okay, and the ambient temperature is low enough to prevent the engine from warming up, I'd try blocking off a portion of the external oil cooler (not that the fender location does a pretty good job of that anyway).

There's always a way to make the engine run hotter; not so easy the other way around.

Sherwood

[spinner37]

wouldn't covering up the vents in the trunk lid help keep the heat in and warm up the motor faster? i was thinking of a nice removable aluminum cover.....

[Formerly Steve Wilkinson]

I dunno...sounds like that would make the cylinder barrels heat up rat quick, maybe too quick too much, but what you really want to be heating is the oil, not the aluminum, I think.

It could be that looking into aircraft preheaters--small but strong silicone-encapsulated heating elements that you could epoxy to the oil tank and/or the sump--would be an interesting path to follow. It's been discussed in numerous threads over the years.

They're thermostatically controlled--heat to a certain temp and no more--and they're safe, because they're FAA-certified, which they have to be if you're going to put them on a certificated airplane. They're not back-pages-of-Car-and-Driver crap by any means, and you won't find them anywhere but an aircraft supply house. I had one on the last airplane I built (which was experimental, not certificated, but never mind) and it worked wonderfully. It was glued to the sump of a flat,air-cooled Lycoming four, and I'd plug it in the night before a morning flight during the wintertime, and the next morning, everything from the wet sump all the way out to the valve covers would be gently warm.

They typically cost about $175 a unit.

[spinner37]

hum, that sounds like the solution.....

[MichaelN]

Interesting thread, and something I'm concerned about myself. What occurs to me is that your commute is short (an that won't likely change) and you want to drive your 911 (and hopefully that will never change). But you CAN change your oil (more frequently, that is). The effects of and harm of condensation do not build up immediately, but rather over time. The trick is to time your oil changes so that you flush out the bad stuff before there is enough of it to create a genuine problem. That way you can continue your routine but eliminate the worry (at a modest increase in operating expenses). Have fun with your 911!

[Canada Kev]

Originally Posted by Formerly Steve Wilkinson

I dunno...sounds like that would make the cylinder barrels heat up rat quick, maybe too quick too much, but what you really want to be heating is the oil, not the aluminum, I think.

It could be that looking into aircraft preheaters--small but strong silicone-encapsulated heating elements that you could epoxy to the oil tank and/or the sump--would be an interesting path to follow. It's been discussed in numerous threads over the years.

They're thermostatically controlled--heat to a certain temp and no more--and they're safe, because they're FAA-certified, which they have to be if you're going to put them on a certificated airplane. They're not back-pages-of-Car-and-Driver crap by any means, and you won't find them anywhere but an aircraft supply house. I had one on the last airplane I built (which was experimental, not certificated, but never mind) and it worked wonderfully. It was glued to the sump of a flat,air-cooled Lycoming four, and I'd plug it in the night before a morning flight during the wintertime, and the next morning, everything from the wet sump all the way out to the valve covers would be gently warm.

That sounds like a great idea, but I wonder if that would make a big difference if your drive was a bit longer, perhaps travelling at a bit higher speeds. Would getting the oil warmed up first help, say if you're driving an hour to the ski hill on roads that are close to highway speeds, but still not working the engine? I think -15 C air flowing at 50 MPH would cool it down pretty quickly.

Shouldn't the T-stat (assuming it is operating correctly) maintain the oil temp even if it's well below freezing? My understanding is that if the stat is closed, the oil will still circulate through the tank and integrated engine cooler, but not to any front mounted cooler. I wouldn't think the engine would have any problems keeping this oil at operating temps, especially with the tank not being in any cooling air stream.

Or maybe I don't have a clue what I'm talking about. Wouldn't be the first time...

[Milo2361]

mickey356 wrote:

What if you drive in a place where the temps are bitter cold in the winter and regardless of how long you drive the car can't get to 194F? Are you not supposed to drive?

I was kinda wondering the same thing. Nebraska winter can get quite harsh.(hasn't yet but i get the feeling its getting there) i have a 6 mile commute in the mornings that i usually turn into about 10 miles and it gets a shade below the top line on the box in this time, at 30ºF. in an attempt to mitigate any misfortune i have caused my engine, on Friday afternoons i take her for a good 30+ mile run at various speeds and gearing to get her oil going.

but last year around mid december, we saw consistent sub 0ºF temperatures. no matter how long i drove it i could not get the temperature up to the line. the oil pressure still dropped like normal, just took a little longer, but the temperature would hardly budge.