temperature gauge question:

[petegtsv10]

I'm curious if other's gauges register like the one in my wife's 135i. It takes several miles to start climbing above 160 and generally settles in at about 2 marks below 250. Assuming that represents 220-230 degrees, I've never owned a car that runs that hot. Is this where others are seeing their gauges??

[edisapimp]

Yup, that sounds about right. Mine operates at 220-230 with normal driving (as per both the Cobb AP and the dash gauge.) When it's hotter out, if I abuse her a little bit for a few minutes, I will see oil temps of 250. It's not uncommon to see slightly higher temps during tracking.

[mturo]

I was shocked when i got mine and saw it running that hot as well.

[gregthegr8]

Once mine is warmed up fully it's always 1-2 ticks below 250 as well.

[JimD]

You know that is oil temperature, right? One advantage of synthetic oil is it breaks down more slowly at elevated temperature. Cars are made to run at higher temperature these days because it improves their thermal efficiency. I've monitored the water temperature in my 128i (using Torque) and was surprised it went pretty high even under light load. I think it is a reason we don't have a water temperature gauge.

[Andrewcoja]

It takes a while to warm up because BMW measures oil temperature differently from other manufacturers. Many other manufacturers measure temperature up in the block where it heats up faster because that's where all the explosions happen. BMW measures from the crank case where it takes longer to warm up but you know when it's warm there, it's up to temperature everywhere.

[ejm3]

Mine runs at the same temps as yours so I guess that's normal.

I was surprised at first too, but this is the first time I've owned a car that measure oil temp not water temp.

When its cold it takes forever to warm up!

[MightyMouseTech]

Originally Posted by Andrewcoja

It takes a while to warm up because BMW measures oil temperature differently from other manufacturers. Many other manufacturers measure temperature up in the block where it heats up faster because that's where all the explosions happen. BMW measures from the crank case where it takes longer to warm up but you know when it's warm there, it's up to temperature everywhere.

The oil is always circulating. Will be pretty much the same temp everywhere. Well, after the oil cooler (if you have the M Sport Pkg) will be a little lower.

Most cars have a coolant temp gauge, not oil temp. That is why it takes so much longer to show as "warmed up". Oil takes a lot longer to get up to temperature than the coolant, and IMHO is a much better indicator of actual engine temperature.

[Motohip]

You guys are lucky you have this guage. I drove like 300 miles with a bad thermostat and didn't even know it.

[CAVU]

I normally run at 230-240, and that is WITH the extra radiator that is part of the PPK2. I realize the extra radiator is for the coolant rather than the oil, but it still suggests (to me) that 230-240 is the design intent for the oil system.

[PopsnBurbles]

240-250 for me and I don't even drive my car hard but I do go through some uphills though

[petegtsv10]

After looking at the manual this AM I realized that the gauge is for oil temp. It still seems so high to me, but "normal" as per your responses. The Mini S we just sold had no oil nor water temp gauge. My 911 Turbo runs a very constant 175 oil temp and 200 water temp. I'll just stop being concerned now.....

[Overpar56]

After I picked my car up in Chicago I was stuck on I-65 South in road construction and I watched the oil temp gauge rise. I started to get nervous but it didn't climb over 250.

Most likely normal.

[daflamme]

Originally Posted by MightyMouseTech

The oil is always circulating. Will be pretty much the same temp everywhere. Well, after the oil cooler (if you have the M Sport Pkg) will be a little lower.

Most cars have a coolant temp gauge, not oil temp. That is why it takes so much longer to show as "warmed up". Oil takes a lot longer to get up to temperature than the coolant, and IMHO is a much better indicator of actual engine temperature.

I don't agree with that because when you have, let's say a blown thermosthat, the water temp is going to rise a lot faster than oil temp, which let's you know there's a problem

[JimD]

Water temperature and oil temperature will follow a similar pattern but are not monitored for exactly the same reason. Water temperature is our indication of an engine overheating or not heating up. We don't have a gauge so we find it is not heating up by the heater working poorly and we find out it is overheating when the warning light comes on. I'd personally much prefer a gauge but I suspect others would be alarmed to see the rise and fall. Our cars are designed to run pretty warm so they will use less gas.

Oil temperature is to tell us about lubrication. If the oil temperature is low, it is a good idea not to try and extract maximum power from the engine (because lubrication is not ideal). If the oil temperature is high, it is again best not to push the motor but we also need to know why it went high. If it stays high for a prolonged period, the oil will start to break down.

The water goes around the cylinders and heads where the temperature of the engine should be maximum so I think it will generally be hotter but it depends a lot on where the sensor is. Oil is in the same general area but also going through the mains of the engine which should be cooler and the camshaft area which also should be cooler.

There won't be huge temperature variation across the engine, aluminum and magnesium are good thermal conductors, but there must be some to move the thermal energy. The thermal energy will always flow from areas of higher temperature to areas of lower temperature.

[rking117]

Yep Oil temp not Coolant. As for coolant temp i thought there was a reading that is stored in the ECU too and that is one of the indicators used to cause limp mode to engage. I just cant remember where i read it.

[mb135is]

Originally Posted by petegtsv10

After looking at the manual this AM I realized that the gauge is for oil temp. It still seems so high to me, but "normal" as per your responses. The Mini S we just sold had no oil nor water temp gauge. My 911 Turbo runs a very constant 175 oil temp and 200 water temp. I'll just stop being concerned now.....

Yea, mine is up at 240-250 regularly. Never got above 270 on track.

I'd be concerned with constant temperature of 175, unless there is something I'm missing. I thought oil is "up to temperature" at 212.

[02rsxpilot]

Originally Posted by MightyMouseTech

The oil is always circulating. Will be pretty much the same temp everywhere. Well, after the oil cooler (if you have the M Sport Pkg) will be a little lower.

This was not my understanding, though I might be misunderstanding your point.

"The temperature of oil on your gauge is not as hot as it really gets. This temperature is an average with oil from different parts of the motor. Some parts are hotter than others. It is said that some of the oil gets as hot as 400° or 500°F in...racing situations." -http://www.bobistheoilguy.com/motor-oil-105/

Using oil to cool and lubricate an engine is a brilliantly complementary design. As the engine heats up, the oil gets thinner, increasing flow, which aids in cooling. Therefore, with the right viscosity (approx. 10 psi per 1,000 RPM), you have a self-balancing system.

Given that different manufacturers may measure the oil temp at different places in the engine, I'm not sure it's reliable to compare from one brand to another.

[petegtsv10]

Originally Posted by mb135is

Yea, mine is up at 240-250 regularly. Never got above 270 on track.

I'd be concerned with constant temperature of 175, unless there is something I'm missing. I thought oil is "up to temperature" at 212.

I've spoken to other 911 owners and they report similar temps. My previous car, a ZO6, would stay under 150 during the cold days in Chicago. It had a large OEM oil cooler w/o a thermostatic control. I think some very high perf cars have some overkill in the oil-cooling area and keep the oil too cool in regular, non-track, situations.

[JimD]

This is an interesting article on oil at high temperatures. His basic argument is that we don't need to worry about oil temperature during normal driving conditions, only on the track. When cars overheat, the oil temperature will rise a little but will remain well within the capability of the engine to handle. What at times gets out of control is coolant temperature.

http://www.bobistheoilguy.com/motor-oil-105/

[CAVU]

Originally Posted by JimD

Water temperature and oil temperature will follow a similar pattern but are not monitored for exactly the same reason. Water temperature is our indication of an engine overheating or not heating up. We don't have a gauge so we find it is not heating up by the heater working poorly and we find out it is overheating when the warning light comes on. I'd personally much prefer a gauge but I suspect others would be alarmed to see the rise and fall. Our cars are designed to run pretty warm so they will use less gas.

Oil temperature is to tell us about lubrication. If the oil temperature is low, it is a good idea not to try and extract maximum power from the engine (because lubrication is not ideal). If the oil temperature is high, it is again best not to push the motor but we also need to know why it went high. If it stays high for a prolonged period, the oil will start to break down.

The water goes around the cylinders and heads where the temperature of the engine should be maximum so I think it will generally be hotter but it depends a lot on where the sensor is. Oil is in the same general area but also going through the mains of the engine which should be cooler and the camshaft area which also should be cooler.

There won't be huge temperature variation across the engine, aluminum and magnesium are good thermal conductors, but there must be some to move the thermal energy. The thermal energy will always flow from areas of higher temperature to areas of lower temperature.

Jim --- kudos to you for presenting this technical information with clarity and accuracy. Well done.

[five_timer]

Originally Posted by JimD

Water temperature is our indication of an engine overheating or not heating up. We don't have a gauge so we find it is not heating up by the heater working poorly and we find out it is overheating when the warning light comes on. I'd personally much prefer a gauge but I suspect others would be alarmed to see the rise and fall.

What I've been told is that over the years, BMW has had to increasingly dampen the water temp needle, to eliminate fluctuations that would be alarming to the driver. When they went to the electric water pump, it got to the point that the needle would need to be dampened to such a degree as to render it useless. So bye-bye water temp gauge.