Hi Folks

Could anyone help me with this first analysis at 55400KM - 3800km on the oil including a few track days.

Reason I ask is that I had a lot of gritty friable carbon deposits in the oil filter and I am having reduced oil pressure levels at idle when hot and hotter oil temps on track, up to 248F lately (at 50F ambient). The oil temps at successive track days have been getting hotter and hotter for some reason.

I'm wondering if the oil cooler is partially blocked with carbon deposits, giving the hotter temps and the carbon deposits in the filter (which I didn't see at the last oil change). I might put a flush through next time? Servicing looks like it's been done properly in the past, But I suspect only at the factory intervals which are way way too high. Oil is Castrol Edge with Titanium 0W-40. The report didn't flag anything as a problem.

Manual car without 3rd rad and normal thermostat.
A130901206_MATT BURTON - AGIP_0 (2).pdf

 

You had an oil test done and it reads no action necessary. What do they say about the carbon deposits? Scope the top end for carbon buildup or cylinder scoring /blowby. Did this start with your choice of oil? How much hotter is motor running? Don't know that 250 is that unusual at track. I would also look elsewhere for the overheating problem if there is one. Water pump, cooling system, radiators etc. Low oil pressure at idle, why? Oil pump ok? Switch oil to Motul? Find a 10-50 wt. Add the radiator? Some report lower running temps w 160 thermostat. I'm not sure why you are asking for help with the oil analysis. Overheating 05 is not a good thing for sure and there are a lot of questions for a good tech to address.

 

They didn't make any mention of the carbon deposits, and the soot levels in the oil were low, so it's been loosened from some where else I guess. I've been running this oil all the time, and previous owners the same. I don't have any other overheating issues and the oil cools down well enough on the cool down lap.
Lower oil pressure - don't know. Used to be 1.5-3 at hot idle, now 1-2 at hot idle. Doesn't use any oil. Oil pump OK? who knows. Pressure at 3-4K rpm seems fine.

 

Castrol doesn't list a 0w-40 with "titanium". You sure you are not running a 0w-30 or something similar? I see several lighter viscosity grades listed "with Titanium".

Castrol does offer a 0w-40 that is Porsche approved (has the A40 on the bottle label).

If the oil pressure is ok the cooler is not blocked with carbon deposits. Hard to create carbon deposits in the oiling system.

The material you are taking for carbon is I suspect something else. If it is hard it could be the composite plastic that covers some chain guide rails. In the 996 I've seen two colors: a medium caramel and a dark -- almost black -- caramel color.

Other hard and dark plastic bits can be the iMS bearing seal material and perhaps even the bearing cage material.

Soft black bits can be camshaft cover sealant or sealant used to seal say the oil sump plate.

250F oil temps on the track is not that excessive. However, I would probably if I were you renew the oil more often than 3800km if you are tracking the car.

The drop off in idle oil pressure can be explained by the oil being overly contaminated and losing some viscosity. As a result oil pressure when hot drops.

Also, the in-dash oil pressure gage is not the most accurate gage around and the variability could be all in the gage.

Last but not least, I would not switch to a 10w-xx oil as none of these oils meet Porsche requirements. There is an approved 5w-50 oil (Mobil 1) that if you can find it in your area might be worth trying at least during the hottest time of the year or during track season, just make sure you give the engine plenty of time to get fully up to temperature.

 

Yes it is Castrol edge 0w-40 (I might be thinking of the 10w-60 for the titanium). I will be going to mobil 1 5w-50 next time or motul etc. The deposits are black in colour, very friable (crumbly) and definitely do not have the consistency of any plastic. Almost crumbles down to a soot in between the fingers, but more gritty than that - but the gritty bits can be further crumbled down.

 

I would reinforce the caveat that if you are finding contamination in the filter there may be a problem with the motor. An idling oil pressure HOT of 1-1.5 is not a problem. A running temp approaching 250 during tracking is not necessarily an issue. But I would be concerned about the filter. Here's a suggestion: run the motor, change the oil and filter again and see if the filter still is still catching debris from the oil. If this has not decreased significantly go to your nearest service shop asap for a diagnostic. Something in the engine is deteriorating/failing. Macster is on the money regarding seals and guides and the IMS bearing. If the oil shows signs of cleaning up significantly perhaps the previous owner was not diligent about the service routine. That and more frequent oil/filter changes would be the best case scenario here imo. By the way this months Excellence suggests that you pull the filter and check inside the oil intake tube from filter to motor to see if anything is getting past the filter. If you find debris has gotten past the filter there is a poor prognosis for your motor. Since the oil anaysis has nothing to report this may not be a problem.