Unusual oil temperatures and oil behavior - 08 S65 142K miles / VAC / CSF Rad

[macdude357]

One thing to check is to drive your car until it's fully warmed up then pull over and see if the oil cooler is hot. It should be around the same temp as the oil. If not, then oil isn't flowing through the cooler.

[roastbeef]

yea, your car is running on the warm side dude. i'd ignore the people saying this is normal. while its not harmful (yet), it definitely isn't normal. i like macdude's suggestion of checking the oil cooler. just stick your hand in trough the felt exit and you should be able to feel the back of it pretty easily.

[CTMike]

I ran in to overheating issues when my radiator fan bit the dust. It was intermittent at first and of course traveling at speed it wasn’t really noticeable. Slow cruising or traffic it became a real problem. Ultimately the fan and fan relay were replaced and a wiring contact repaired... no issues since.

[jeremyuhh]

Originally Posted by amrazM

check coolant temps, if coolant is going above 192* during normal operation something is wrong.

Coolant temps were 203F according to Carly app after exiting the freeway. (Not sure how accurate that is) Uphill highway driving, not speeding, not pushing it. All normal driving. 206F when I got to my garage.

I'm guessing a thermostat isn't opening or serious blockage from the ac condenser. It has a new CSF radiator.

And oil temps were high as usual.

[Ervin87]

Thermostat is definitely opening, otherwise car would overheat very quickly.

Your coolant temp sensor seems fine. Temperature will go over 190 depending on conditions, but eventually should come down.

Your temperature is definitely on the hot side, as those are the temps one would see on a track day of a 20 minute high RPM session, but they would come down 30 seconds after a cool down lap.

Have you had a chance to look at the oil cooler and see it's condition?

[jeremyuhh]

Originally Posted by Ervin87

Thermostat is definitely opening, otherwise car would overheat very quickly.

Your coolant temp sensor seems fine. Temperature will go over 190 depending on conditions, but eventually should come down.

Your temperature is definitely on the hot side, as those are the temps one would see on a track day of a 20 minute high RPM session, but they would come down 30 seconds after a cool down lap.

Have you had a chance to look at the oil cooler and see it's condition?

thanks. temps didnt go down after exiting the freeway. it kept going up. about a half mile to my house from the exit, no traffic, had air flow, no crazy acceleration.

right? those were the temps ive seen at the track in my old M3 and it would cool down rather quickly. This M3 is doing the opposite.

The oil cooler has a few fins bent, a small rock stuck in there from what i can see through the grill. Im going to pull the bumper off tonight to install a lip and will inspect and the rads and coolers then.

[jeremyuhh]

Originally Posted by CTMike

I ran in to overheating issues when my radiator fan bit the dust. It was intermittent at first and of course traveling at speed it wasn’t really noticeable. Slow cruising or traffic it became a real problem. Ultimately the fan and fan relay were replaced and a wiring contact repaired... no issues since.

my fan works cause i can hear it with my windows down as im driving through my complex, and it stays blowing at its low setting and sometimes high setting after shutting the car off.

[akkando]

Is it possible the thermostat was replaced with one that opens at a higher temp?

[Helmsman]

Originally Posted by jeremyuhh

Coolant temps were 203F according to Carly app after exiting the freeway. (Not sure how accurate that is) Uphill highway driving, not speeding, not pushing it. All normal driving. 206F when I got to my garage.

I'm guessing a thermostat isn't opening or serious blockage from the ac condenser. It has a new CSF radiator.

And oil temps were high as usual.

Sure coolant temp raise above Tstat (79C) when stand still and stop/go traffic but as soon as you get airflow it should come down to around 80C again. Either Tstat, radiator/air flow (or coolant..?) seems to be failing here.

[amrazM]

that 206*F is way too high on the coolant temp, that is the direct cause of why the oil temp is so high. My guess would be a blockage or lack of flow.

start by pressure testing the cooling system see if it holds pressure, then check operation of the waterpump and the thermostat. something in that cooling system isnt working

[amrazM]

could also be possible the cooling system isnt bled properly as I see you mentioned having replaced the radiatior.

[Ajolives]

Originally Posted by amrazM

could also be possible the cooling system isnt bled properly as I see you mentioned having replaced the radiatior.

I've been told they're self-bleeding, but I still bled mine a couple times after doing my OFHG. Couldn't hurt to bleed.

[amrazM]

Originally Posted by Ajolives

I've been told they're self-bleeding, but I still bled mine a couple times after doing my OFHG. Couldn't hurt to bleed.

no such thing, you still have to belch the cooling system once air gets into it. Im curious to know if these high temps the OP is displaying happened after his new radiator

[jeremyuhh]

Originally Posted by Helmsman

Sure coolant temp raise above Tstat (79C) when stand still and stop/go traffic but as soon as you get airflow it should come down to around 80C again. Either Tstat, radiator/air flow (or coolant..?) seems to be failing here.

Originally Posted by amrazM

that 206*F is way too high on the coolant temp, that is the direct cause of why the oil temp is so high. My guess would be a blockage or lack of flow.

start by pressure testing the cooling system see if it holds pressure, then check operation of the waterpump and the thermostat. something in that cooling system isnt working

Originally Posted by amrazM

could also be possible the cooling system isnt bled properly as I see you mentioned having replaced the radiatior.

Originally Posted by Ajolives

I've been told they're self-bleeding, but I still bled mine a couple times after doing my OFHG. Couldn't hurt to bleed.

copy. it was replaced 3 years ago though. Im sure the previous owner would have caught it if the system wasnt bled properly. But is there a possibility of air seeping in some how ?

i have a coolant temp sensor, temp sensor harness, and thermostat on the way. Havent had a chance to pull off my bumper yet.

Also, how long/quicky does it take your guys cars to hit 210F/operating temp ?
I took a short drive this morning from a dead cold start, about 1.5 miles up hill and my needle was already in between the first dot and 210F, closer to 210F.

Also noticed the car hesitating before firing up. about 2 seconds before it turns on. Thinking this is battery or alternator related.

[Ajolives]

Originally Posted by amrazM

no such thing, you still have to belch the cooling system once air gets into it. Im curious to know if these high temps the OP is displaying happened after his new radiator

Thanks, I thought it was BS too, but this is my first BMW so I wasn't sure.

[Ajolives]

I'd say mine takes a solid 7 minutes or so, roughly 3-5 miles to get up to temp.

In the summer no more than 5 minutes.

[Helmsman]

Originally Posted by jeremyuhh

copy.

Also, how long/quicky does it take your guys cars to hit 210F/operating temp ?
I took a short drive this morning from a dead cold start, about 1.5 miles up hill and my needle was already in between the first dot and 210F, closer to 210F.

Good question. Mine (like most?) doesn't come up to full temp on my 8 miles/12-15min commute to work. I'd say a good 20min regardless of Summer/Winter (and still halt just below mid gaugh/97C isch but that seem to differ between cars).

Even if the Tstat was completey destroyed/closed, I can't see how that would make the engine temp raise that fast. Same thing with the oil cooler/Tstat, even if wrecked, it should't impact the actual warm up pace as its should be closed till it get up there anyway? Sorry, but clueless here mate.

[atopa2002]

Originally Posted by jeremyuhh

copy. it was replaced 3 years ago though. Im sure the previous owner would have caught it if the system wasnt bled properly. But is there a possibility of air seeping in some how ?

i have a coolant temp sensor, temp sensor harness, and thermostat on the way. Havent had a chance to pull off my bumper yet.

Also, how long/quicky does it take your guys cars to hit 210F/operating temp ?
I took a short drive this morning from a dead cold start, about 1.5 miles up hill and my needle was already in between the first dot and 210F, closer to 210F.

Also noticed the car hesitating before firing up. about 2 seconds before it turns on. Thinking this is battery or alternator related.

Change the water pump too.

[Helmsman]

Originally Posted by jeremyuhh

Also noticed the car hesitating before firing up. about 2 seconds before it turns on. Thinking this is battery or alternator related.

Hmm...when I replaced my couple of month ago I forgot to fill up the cooland and tried to start. Engine hesitated (which it never done), and I immediately realized my s-w up. Wondered a little over this but couldn't think of a sensor other then the coolant level that would understand that there was not enough coolant. Your coolant level is obviously in place, there isn't another sensor that understand abour cooland flow, while you have air in the system...? Very long shot without any knowledge behind.

[jeremyuhh]

Originally Posted by Helmsman

Hmm...when I replaced my couple of month ago I forgot to fill up the cooland and tried to start. Engine hesitated (which it never done), and I immediately realized my s-w up. Wondered a little over this but couldn't think of a sensor other then the coolant level that would understand that there was not enough coolant. Your coolant level is obviously in place, there isn't another sensor that understand abour cooland flow, while you have air in the system...? Very long shot without any knowledge behind.

Opened up the reservoir and coolant is at max.

I also spoke to a reputable shop in the San Fernando Valley and was told if im not throwing codes, things should be normal - but theyre not. They also recommended to check to see if there is blockage in any passage. And to also inspect all the radiators and coolers.

[jeremyuhh]

Pulled the bumper off just now and this is the state of my condenser and oil cooler.

How bad does this look and could this be the culprit ? Going to clean and straighten out every fin I can.

[jeremyuhh]

Cleaned and straightened out almost every fin. Took out countless pebbles and debris.

Amazingly, I could see a difference in oil temp behavior just from the gauge. On highway and street driving, the needle would drop down just before 210F while moving and would not go passed 210F. Straightening the fins and clearing the debris made a huge difference...

BUT

before i got on the freeway, i shut the car off just before it got to operating temp, the fan stayed on. (ambient temp was 65F) Which is really strange because it would only stay on, at its fastest setting, after shutting down at high temps before i cleaned and straightened it (~230F)

now, headed home after driving on the freeway and seeing the temps cool as they should... after i exited and was driving at low speed (20 MPH) in about a 1/4 mile, temps slowly creeped above 210F as i approached my complex and crept up even more as i entered my gated community at a speed of 10 MPH...

which leads me to believe something is up with the fan as CTMike mentioned. The fan operates but i think whatever sensor connected to it is acting up.

and another big finding: macdude357 i felt my oil cooler after coming home from about 20 miles of freeway driving and it was stone cold. Any idea where to start checking for blockages ?