3.2 carrera operating temp

[parmenide]

I've had my '89 Carrera Targa for about a year, 43k+ on the clock.. SW chip, bypass, diff, muffler, and a boatload of suspension work.

I should know the answer to this basic question but here it is -- what should the operating temperature be during idling after a driving the car for a while? This morning I went on a 40 minute drive in probably 80 degree weather, fairly humid. During the drive the temp was at 8 o'clock position, maybe a bit less. When I got home I decided to check the oil (and added some) and while the car was idling (5-10) I noticed the temp climbed to the 9 o'clock position, and I've seen it a touch over 9 on another occasion while idling after a hard run. Is this normal? I am wondering if there might something going on in the oil cooler.

[86 911 Targa]

Originally Posted by parmenide

I've had my '89 Carrera Targa for about a year, 43k+ on the clock.. SW chip, bypass, diff, muffler, and a boatload of suspension work.

I should know the answer to this basic question but here it is -- what should the operating temperature be during idling after a driving the car for a while? This morning I went on a 40 minute drive in probably 80 degree weather, fairly humid. During the drive the temp was at 8 o'clock position, maybe a bit less. When I got home I decided to check the oil (and added some) and while the car was idling (5-10) I noticed the temp climbed to the 9 o'clock position, and I've seen it a touch over 9 on another occasion while idling after a hard run. Is this normal? I am wondering if there might something going on in the oil cooler.

Your '89 should have an oil temp fan on/off sensor located on the top of the front oil cooler.

Unfortunately, this sensor does not activate the fan until the oil temp reaches 246f.

Ouch!!!!!



^^^^^
My fix for this.

https://www.nasonptc.com/

The sensors can be ordered for a on/off temps as needed.

Ours is:

ON: 205f.

OFF: 197f.

Also, replaced the red/white gauge insert with a numbered insert.

Best,

Gerry

[kanadary]

Mine no mods at all other than Euro height which I don’t think makes any difference. Oh it does have that air scoop thing that pelican sells for the fender cooler but not sure that is effective. Anyways it runs just below the midpoint on the temp gauge

[VMAX1]

Take a flashlight and look into the far left side of the gauge, the temp marks are there. I replaced the oil thermostat for the front oil cooler, inside the right rear wheel, and stays below the 9 o'clock mark and would tick above the 10 o'clock before replacing. 43K miles is low, but a lot of years on her. I installed a switch to turn on the fan for the oil cooler, behind front right wheel.

[spuggy]

Originally Posted by parmenide

while the car was idling (5-10) I noticed the temp climbed to the 9 o'clock position, and I've seen it a touch over 9 on another occasion while idling after a hard run. Is this normal? I am wondering if there might something going on in the oil cooler.

Sounds perfectly normal to me.

The design uses two things for cooling; air and oil. The car can cool itself perfectly well cruising on the freeway unless ambient temp is insanely high; because once it makes enough RPM to have good air/oil flow it's fine. And moving down the road doesn't hurt either.

At idle, oil flow is at the minimum. And so is the oil pressure. At least the oil isn't thick and sluggish - that's why the owner's manual says start it and drive away immediately from cold; don't idle it.

The 245mm 930 fan apparently moves 1500 litres/sec @ 6000 RPM with a 1.68:1 pulley. At idle? Yeh, uh, not so much...

There's no airflow from moving - so your front scoop does nothing. If you're not moving and the cooler fan isn't running, the cooler can't radiate heat away anything like as efficiently as it can shed heat with airflow.

When the car is already at a normal operating temperature and you simply idle, the heat generated by running exceeds the minimal capacity of the cooling system with no meaningful RPM/airflow. Temperatures rise. Quite rapidly.

I have a FMOC; gauge in the car reads 175F unless I pull boost. Then it may read as high as 210F briefly. If I get stuck in traffic for prolonged periods, temperatures get hotter than that. To the point where I start thinking about localized hot spots, oil breakdown temperatures (115C, BTW) - and might resort to holding 2000 RPM to get more air over the engine oil cooler and through the shroud...

So let's put that another way; car gets hotter idling in traffic than running around the track. It doesn't hurt that moving large amounts of air through the engine bay keeps that around ambient. But the bay will heat soak at idle, or once the motor is stopped; my intercooler IAT spikes 25-30C over ambient if I stop for 3 minutes to buy smokes.

Last log when I futzed with the Motec idle, CHT rises ~45C (from 123C to 168C) and the chaincase oil sensor rises from 67C to 85C. In not quite 3 minutes.

There's a 195F thermoswitch (from a BMW, I think) you can fit to the Carrera cooler, which may help get in front of oil temperatures somewhat. But that will do nothing for cylinder head temperatures - they need oil and air flow.

[ganun]

Gerry has good advice. Did it on my 87 and it keeps it at 8 o'clock.
That is if the thermostat is operating properly
Both lines under the front right fender going to the cooler should be too hot to touch

[parmenide]

Thanks for the thoughtful and detailed responses and advice guys!! I figured it needs air flow to keep it cool, but I had a 964 a long time ago and don't remember it ever running very hot even when idling. When I get to may next round of change to the car, I will look into a different sensor.

I'll be bugging you all regarding oil consumption at some point..

[adias]

PAG says that 220F is perfectly normal wig excursions to 250F. These engines run hot.

[stlrj]

I'm assuming you had the SW chip done while you owned the car. Did you notice any temperature difference after the install?