Hey Andrew D
In order to do a "strip down" inspection the turbo needs to be completely removed, without complete removal there is nothing that you can do.
Once you have completely removed the turbo, the compressor housing (that's the silver coloured cover) can be unbolted (6 x 10mm headed bolts).
Once this is done the nut on the end of the intake impellor shaft is undone and the compressor turbine can be removed, this normally means VERY GENTLY tapping the turbine shaft all the way through the bearing housing using a brass punch (very thin), the exhaust turbine is part of the impellor shaft so they come out together from the exhaust housing side. You need to remove the oil feed housing, normally four bolts with locking tabs on them, once the oil feed housing is removed from the main body, you have access to the turbine bearings, these are held in place by circlips, when removed the bearings can be taken out. Inspection of all components is about wear, and free play, so access to manufacturers tolerances for the turbo would be a good idea. Make sure you get a turbo seal set organised before you start as all "O" rings and gaskets must be replaced during re-assembly, and whilst you have it in bits new bearings are a good idea too.
Cleanliness is essential once you have it on the bench and ideally stripping and assembly should be done in a dust/grit free environment, (I used to strip them for test examination in a "clean room"), the kitchen table is quite a good place too!!
Measuring axial play, end float, and preloading of the bearings is VERY important too, reassembly of the shaft is critical, too tight and the turbine will bind on the bearing housing, too loose and excessive axial play and the impellors will rub on the compressor and exhaust housing which will cause damage the internal faces of the housings and allow the swarf (on the inlet side) to enter the engine through the air intake and then it's all over!!
And just as important as all of the rest of it, is, make sure you prime the turbo with engine oil as you build it and prior to firing the engine up, the bearing don't last long without oil!!
Unless you are a competent mechanic (I'm sorry I don't know what your experience is) with experience of turbo's and a good set of tools, I wouldn't touch it, most dealer workshops either replace them as a unit, or send them away to a specialist.
Having said all that, if you are able to do it, there is nothing more satisfying that rebuilding something for yourself and seeing it work perfectly. Good luck.
MAP
