Here's a cut and past of the relevant posts:
Well, I now have the old IMS bearing. First things first, I am no engineer despite working for an aerospace engineering company! My photos and commentary are merely observations.
For context, and repeated from earlier posts, the car is a 2004 986S with 105k miles. No paperwork but confirmed decent history from OPC with regular servicing. I don't know for sure but I believe the car was a daily commuter although the condition of the interior suggests a car with half the miles and a weekender. I believe the oil changes were all done with 0w40 Mobil 1 (oil change prior to sale was and this spec oil is what OPC use).
The original NSK bearing was replaced with an LN ceramic one as part of a schedule of works including a clutch change.
Russ commented that this was one of the most solid bearings seen. Holding the threaded shaft and wiggling the bearing shows no play at all. Holding the shaft and attempting to spin the bearing by finger then next to noting happens. You have to maintain contact with the bearing outer race and rotate it rather than spin it. Whewn turning it there is no notchiness, the movement is very consistent and smooth. There are no weired noises.
The seals seem completely intact, no pitting or any sign of damage. There is a small indentation on one part of the seal pictured below but I presume this was done at removal or in transit via post. The outer race has some light markings that go round the circumference. Running your nail over them you cannot feel them.
Old bearing:
Marking around circumference:
Indentation on seal:
When I get the chance I will remove the seals and have a look inside.
Here is the next IMS instalment. The seals are now removed. Again, take what I say with a pinch of salt. I don't see many bearings in different states of ab/use.
To remove the seals was reasonably straight forward. The smallest flat blade bit pierces the seal. Trying to lever it out on the outer edge proved pretty hopeless.
Here is one side of the bearing opened up.
Nothing much untoward here:
Back of the seal was pretty clean, no real evidence of any debris:
In this shot I wiped my finger over some of the ball bearings. You can see at the 3pm position the bearing is cleaned of grease/oil and is silver. The bearings are otherwise covered in a light film of grease/oil which has a silver (probably metal) tinge to it.
This shot shows the seals and various finger wipe marks to show the colour of the oil/grease inside the bearing. It seems evident that oil has got past the seal but is generally a golden brown colour and the same sort of colour as a good clean oil. The grey smears are what has come off the face of the ball bearings:
