targa996

Did oil change today (1 year 4500 miles on oil - 62K on car) - 8.5qt Mobil 1 0W40, Hengst Filter. WHile I was under the car I noticed a oily area just behind the oil filter. Mostly dried on / dirt - but there was one small moist drop (I didn;t notice any oil drops on garage floor yet. Is this RMS area ? Do I need to take care of this right away or it is OK to wait until it gets worse (and/or I do the clutch anyway).

(Wiped dirt/oil from area indicated by red arrow - picture is taken from oil filter area looking towards driver side of car). There is quite a lot of oily residue around back of transmission area - not sure how long it has been there - perhaps since PO - RMS was done in 2006.

No metal on mag drain plug and I pulled apart the old filter element and it looked clean (on metal flakes). Will send sample to Blackstone for report.

Also noticed coolant level was slightly below minimum mark on the expansion tank. I added 1 pint of Pentosin SF (50/50 distilled water) and the level was still only on the min mark (cold). Is that normal ? Coolant level has been close to min mark since I got the car and I never worried to add before - seems like a pint is a lot to add for only moving less than 1/2 inch or so up the expansion tank ? I don;t see any obvious sign of leaks or water staining - but could be due to water pump soon. That is probably my next DIY.

fpb111

That appears to be where the RMS and/or IMSB leaks show up. Oil "leak" not enough to worry about.

Keep an eye on the coolant. The Min mark is for cold, Max hot. If you fill to max cold it will vent out when it gets hot and expands. Then you will have a coolant "LEAK" to worry about.

TomF

Could be that your AOS bellows is failing. It can cause a really oily mess all over... At 62k and the age of your car, it could be suspect..

Cheers,
TomF

KrazyK

If you would clean everything first, it can help you pinpoint any leaks. Thats quite the mess under your car and may make it very hard to locate the source. It should look like this:

targa996

Yeah - maybe failing AOS explains high oil consumption ? That is also a job to do when I need clutch - unless things get worse before then. KrazyK - how did you clean under there - steam ? or spray on engine degreaser ? Thanks

TomF

Keep in mind that coolant loss can also be caused by a cracked AOS. That was happening on my car. One of the coolant attachments had cracked and was leaking a bit.

Best,
TomF

KrazyK

It wasnt bad because I dont have any leaks. I hand spray degreaser or brake cleaner (with mask of course) then scrub with different size brushes.

It will be much easier to see any leaks when you are done. Thankfully mine remains this clean (so far).

perryinva

Could also be the O-rings on the oil cooler, as it is coolant cooled. It is located right over the top of where the oil filter is and was the source of a similar mess on my car. Pics in this thread: https://rennlist.com/forums/996-foru...orth-it-2.html

Which started and ended as a motor mount thread, but got side tracked in the middle. My AOS, which I also replaced at the time, was also blowing a little oily mess through the o-ring, which looked as if when it was installed, the o-ring was damaged. But that is on the other side of the engine, not near the oil filter.

The oil cooler leaks (on my car) were very slow, likely only happening when the cooling system was under full pressure, causing a slow loss of coolant, which replacing the o-rings has stopped completely. There appeared to be no oil leaks from the o-rings, but it was only a matter of time, IMHO.