Oil temp too high

[Vincent 911]

Today after 5 laps of track (2 mi per lap) my oil temp needle was entering the red section. And I have notice a significant loss of power as well. So I pulled to the pit immediately.
Then on my way back (150 mi) the oil temp was still high but not alarming: 5th gear, 3000 rpm, see the picture.

It is not really warm yet in MI so I am a little bit concerned for this summer.

What should I start to check? My front oil cooler is hot. It is a trombone type. It has a layer of Blackstone on it: would it be my issue? I have cleaned the oil cooler in the engine. When overheating, the engine doesn't not seem to be so hot: I can touch it without burning myself: sensor issue?
I need to check the advance as well.
What is typically your operating temperature range?

Thank you

[vash]

the loss of power makes me think that the gauges are accurate. i think you need a carrera cooler with a fan. on the track, my needles is a bit lower than in your pick. almost, but not quite to 9:00 oclock. driving in the heat,on the hwy, i see 8:00 oclock no matter what.

nice car, btw!

[boyt911sc]

Vincent,

That's exactly what happened to me at the track. The temp. went well over the 10 o'clock mark and encountered significant power loss. The other SC car in the same run had very hot trombome cooler while mine was just 'warm' to the touch. The culprit: auxiliary thermostat was defective.

After replacing the auxliary thermostat and adding a Carrera oil cooler, never again I experience any sign of overheating in the track. Installing an auxiliary cooler whether fender or front mounted is highly recommended for cars doing track events.

Tony

[Chuck Moreland]

Check the on-engine thermostat. They sometimes fail.

[Vincent 911]

Thank you for the precisions.

1- Auxiliary thermostat defective: maybe. My front oil cooler was warm but I didn't burnt myself.
Does it mean it would not fully open? How can I check it? The oil lines are stuck on it: I have tried to remove it but I was not succesful.

2- Engine thermostat: how do I check if it opens correctly? Remove CIS + shroud

I will consider to mount a Carrera oil cooler and make some researchs on this upgrade.

[tcar]

If the trombone was just warm, something is wrong. It should be 'ouch' hot.

Are your oil lines crunched? if they're OK. That happens when a jack is placed under them. Not enough oil gets to the cooler.

Thermostat may not be opening, that could be culprit if lines are OK.

Find out what is wrong before trying to change to a different oil cooler; it won't help.

Why were you trying to remove the cooler?

[boyt911sc]

Vincent,

Removing the thermostat is mandatory if you want to test it. The test is very simple and easy to do. But getting this auxiliary thermostat off from the 4 oil lines sometimes pose the greatest challenge. I would suggest that you drop the complete oil line assembly for the auxiliary thermostat and cooler (trombone). Having this out from the car will give you more leverage in dismantling the oil line connections. Just be aware that you could damage the thread on the thermostat housing if you forcibly remove the flare nut/s. Apply heat and penetrating oil as needed.

A good auxiliary thermostat will start to open around 180°F give or take a few degrees. You could use either a water or oil bath to do this test. I like to use a water bath because it boils at 212°F. If you pull out the thermostat from the boiling water, the aperture opening should be more than 25% (just a guess-timate).

Tony

[JeremyD]

If you got into the red - change your oil - unless you are running a full synthetic - significant oil break down can and will occur above 250 degrees

[patkeefe]

If you search the word "oil" and my username, you will find lots of info on oil temps: the good, the bad and the ugly. I am working on a new front cooler, to go in series with the fender mount cooler. Check your thermostat as suggested, and the trombone is likely not enough for the track.

Track Oil Temps???

Pat

Pat

[Vincent 911]

Thank you for your feedbacks. I will work on the thermostat Saturday. Wish me good luck with the stuck oil lines nuts.

Do you think this kind of oil scoop will help to significantly decrease the oil temp with the trombone?
Have you ever done this upgrade and are your conclusion?
If it works it could be an interesting solution for me because it won't modify the car too much and will be able to come back to the original set up.

[stlrj]

Originally Posted by Vincent 911

Today after 5 laps of track (2 mi per lap) my oil temp needle was entering the red section. And I have notice a significant loss of power as well. So I pulled to the pit immediately.
Then on my way back (150 mi) the oil temp was still high but not alarming: 5th gear, 3000 rpm, see the picture.

It is not really warm yet in MI so I am a little bit concerned for this summer.

What should I start to check? My front oil cooler is hot. It is a trombone type. It has a layer of Blackstone on it: would it be my issue? I have cleaned the oil cooler in the engine. When overheating, the engine doesn't not seem to be so hot: I can touch it without burning myself: sensor issue?
I need to check the advance as well.
What is typically your operating temperature range?

Thank you

How long have you owned it and has it always been this way?

[Deschodt]

All of the above answers are correct, but know that after you fix your thermostat, check your lines for crushed areas, install a carrera cooler, a Fan on the cooler, extra scoops and opening for airflow etc, it will still run pretty hot on track ;-) SCs do that ;-) Just not in the red zone, hopefully !

I'm surprised no-one mentioned the swamp cooler yet ;-) (it works)

[tcar]

Oh, yeah, Grady's Rubbermaid (or was it Tupperware) solution.

[scarceller]

How about a possible lean condition? like a air leak that has come up in the intake?

Do you have a AirFuelRatio meter (Wide Band O2 device) installed?

Lean mixtures will very quickly result in cyl head temps to rise. When the fuel mixture goes lean it causes the flame front to slow and not move as rapidly as it should outward from the spark plug. The end result is heat that does not result in mechanical energy, this extra heat must then be absorbed by the cyl and heads.

Double check you are not running lean on the track, most important your AFR should be down near 13.0:1 in wide open throttle.

The other possibility is a faulty WOT switch if you run the stock motronic system. If the switch is bad you will not get the WOT fuel maps engaged.

[Vincent 911]

An update:

I did have a look to the oil lines: I have 1 crushed main oil line (the one under the right side rocker panel). It looks pretty bad. Therefore I have removed the whole assembly: oil lines + thermostat + trombone.
I have heated and soaked the threaded connections and already loosed pretty easily two of them (main oil lines to thermostat).

Tomorrow I will continue: check thermostat and 'uncrsush' the oil line. I will use the pressure and heat trick. I have plan to get rid of all the Blackstone on the lines as well.

Next step: Carrera oil cooler. I am looking for a used one and oil lines + brackets + stone guard + seal... No fan for the moment. Anybody sell one?

After: adjust timing again. It might have changed during the track session. How can I check if I need to rebuilt my distributor?

For the track: I could remove the right blinker assembly to get more ram air to the oil cooler if I still have some heating issues. What do you think?

My engine is an early 3.0L without O2 sensor. I will still need a mixture adjustment.

Thank you.

[Vincent 911]

Here is how the oil line looks like:

BTW I have a hell of a pain to remove the 4 other oil line nuts. I tried heat + PB Blaster but nothing moves Therefore I cannot check my thermostat because it is still attached to 2 oil lines and I cannot remove the trombonne as well.

Tomorrow I will put pressure in the crushed oil line and heat it and see if cit omes back to its original shape.

[SCWDP911]

ouch! I am not that familiar with this issue and so I am curious to hear those of you in the know whether or not this is crushed enough to cause his high temp...

[scarceller]

Originally Posted by Vincent 911

Here is how the oil line looks like:

BTW I have a hell of a pain to remove the 4 other oil line nuts. I tried heat + PB Blaster but nothing moves Therefore I cannot check my thermostat because it is still attached to 2 oil lines and I cannot remove the trombonne as well.

Tomorrow I will put pressure in the crushed oil line and heat it and see if cit omes back to its original shape.

WOW, I'd say that would restrict oil flow.

This brings up another question: so if the thermostat for the front cooler comes on does it simply try to route all oil fluid to the front cooler? Meaning once it's on it cuts off the bypass side of the thermostat? If this is the case it will certainly raise the oil temp real quick, must faster than if you did not have the cooler at all.

Thoughts?

[patkeefe]

I believe the bypass on the external thermostat has pressure relief to prevent the condition Sal asks about.

[Vincent 911]

An update:

The good: I have removed the 2 connections between the hard oil line and the trombone. So I was able to repare the crushed oil line: 80 psi of pressure with a bike pump + heat with a propane torch. The line looks much better now but not perfect. You can still a crushed area but not as bad on the picture.

The bad: I am still not able to loose the 2 remaining connections on the thermostat. I was starting to use brute force so I decided to stop before braking something. Therefore I cannot check the thermostat but with the heat of my torch on the lines I saw the piston opening. Is it sufficient? I don't know.

Here is what I did after: I put the whole thing back in the car. I have also changed the oil as it was very hot. I am in the process to clean the inside of the distributor as well. I suspect the timing advance changed after my first run on the track. BTW I found a other good thread about this task thanks to the Pelican community.
I hope the thermostat is fine. If the oil temperature is still too high I will get a new thermostatt and 2 new oil lines (the one between the thermostatt and the oil tank & the engine). I am also working on the Carrera oil cooler update.