Oil temp over 210F while it's 105f /40c outside. Normal?

[Amos]

Both my oil and water temp climbed slightly past the middle mark while driving in stop and go traffic for an hour. AC on.

I don't recall seeing this before but then again, we haven't really had summers like this before.

Cooling system items replaced in the past 5 years:
Thermostat
Water pump
Temp sensors
A couple coolant hoses, don't remember which
All pulleys, belts, and tensioners
Fan clutch


Normal temp or should I start thinking about a new radiator? A new oil cooler?

I know the manual says it's ok for the water temp to go to the 2nd line but I don't remember my oil temp going past 210 during city driving, even in the heat.

[Cronenberged]

When was the last time you performed a coolant flush? The combination of stop-and-go traffic, heat radiating from the concrete, and the exhaust of nearby cars can lead to increased temperatures. While I only have a puller fan, I recently conducted a coolant flush. During a standstill traffic situation, after around 15 minutes, my temperature gauge gradually moved above the center mark. This occurred on a day with high temperatures in the 90s, along with 100% humidity. My car features an OE radiator. In the maintenance thread, Obidian pointed out that our vehicle significantly benefits from a brake and coolant flush every 2 years.

[eacmen]

I don't get concerned about oil temp until it his the 3/4 mark on the gauge.

[Amos]

When was the last time you performed a coolant flush? The combination of stop-and-go traffic, heat radiating from the concrete, and the exhaust of nearby cars can lead to increased temperatures. While I only have a puller fan, I recently conducted a coolant flush. During a standstill traffic situation, after around 15 minutes, my temperature gauge gradually moved above the center mark. This occurred on a day with high temperatures in the 90s, along with 100% humidity. My car features an OE radiator. In the maintenance thread, Obidian pointed out that our vehicle significantly benefits from a brake and coolant flush every 2 years.

4 years since coolant drain and fill, I've never done a flush though. I should probably do that

[cobra]

Mine will go up there on real hot days when climbing a hill. As long as it doesn't keep going up...

[Arith2]

What concentration of coolant did you use and was it BMW coolant? While I'm inclined to say this is not an issue, it may be time to preventatively replace that 220k radiator. Do you have all your fan shroud parts intact? What condition are your underbody panels in?

[Amos]

What concentration of coolant did you use and was it BMW coolant? While I'm inclined to say this is not an issue, it may be time to preventatively replace that 220k radiator. Do you have all your fan shroud parts intact? What condition are your underbody panels in?

It was the OE BMW coolant, mixed 50/50 with distilled water.

The fan shroud is perfect, the plastic skid panel below is a bit mangled, I'm actually replacing it with an aluminum piece

[S54330Ci]

After hard 20-minute track sessions my oil temp is in the same place (all stock cooling components). Perfectly normal. I'd be concerned when the needle moves past the first dot to the right of center. Just make sure you are using a high-quality motor oil (Liqui Moly) and change it often.

[bigjae46]

4 years since coolant drain and fill, I've never done a flush though. I should probably do that

Drain and fill every 2 years.

[jayjaya29]

Normal. Modern oil is good up to 275F (135C).

[terra]

That oil temeprature seems pretty normal to me for those conditions. But in general if oil is running significantly hotter under the same conditions than before, that could be a sign that there's some extra friction (i.e rod bearings).

[eacmen]

While we're on the subject. I'm curious if anyone knows how much does coolant temp really affect oil temp and visa versa?

[0-60motorsports]

LOL yes very normal. You should clean the radiator, condensor and oil cooler from the back and front and then check if you notice any difference. Also do a coolant flush and check the other items like Aux fan and Fan clutch.

[bigjae46]

While we're on the subject. I'm curious if anyone knows how much does coolant temp really affect oil temp and visa versa?

I used to think that but I don't think there's a direct correlation for small increases. If the coolant system is not working well then I'm sure it results in some extra heat into the oil.

What I've learned about cooling is aerodynamics plays a massive role in cooling performance. Its about getting air to flow through the cooler and the backside flow is probably more important. If the oil cooler was ducted out of the bottom like the E9X M3 then you should see some pretty good cooling gains.

I've been thinking about a duct behind the radiator through the hood. Then I can mount an oil cooler on the back of the radiator, eliminate the external oil thermostat and better control oil temps (cooling AND warming). So in that case, coolant system performance should affect oil cooling.