bearfoil - I choose my words carefully, and I try not to give offence and avoid sarcasm. Also I try not to be light hearted but it's a bit difficult when faced with some posts.
But to get to your point.
No, I don't think the offset counterbore is wear, the surface is too uniform. It appears to be a false cut during manufacture.
I do not understand the geometry of the component as depicted in the photo, and I have no idea of the mating parts and surrounding scenery. Hence I find myself unable to comment.
Oh, all right, then, the stub pipe could be an integral part of a housing casting, in which case the counterbore could have been done on a boring machine. An accidental offset of the spindle would have done the trick.
I honestly think we need more information such as a detailed GA or the relevant pages of the Overhaul Manual before we can get down to informed speculation.
I do not believe there is any fancy aspirator type device involved. The counterbore looks tailor made for a pair of O rings. I would not expect lubrication to be by means of a mist. Oil jets more likely.
As Iomapaseo often says, we should leave the real professionals, Investigators, RR and so on to get on with the job. I have no doubt that they will do a terrific job.
Trouble is, I find it impossible not to respond to some of the more extreme imaginings found on here.
Oh, and can we be a bit more careful with the vocabulary please, and only use terms that are recognised in the Trade.
Last edited by CAAAD; 5th Dec 2010 at 18:17.
Reason: comedian