Background:

I recently purchased a 1989 760 Turbo wagon (120,000 km) which had had a new Mitsubishi turbocharger installed to cure a severe oil burning problem (this did in fact solve the problem). Since then, the engine has sprung a couple of oil leaks. The first one was due to a bent flange on the turbo oil return pipe (this has been fixed). The second appears to be leaking from the area of the rear camshaft seal between the distributor and the head. I'm a little concerned now that the crankcase ventilation system may be allowing positive pressure to build in the case.

Questions:

1. How does the crankcase ventilation system work on the B230FT?

2. How can I diagnose whether the system is working or not? - do I simply remove and check the contents of the plastic box attached to the engine block under the intake manifold for fouling?

3. Can anyone recommend a good shop manual for this car? This is the first car I've owned which does not have a readily available factory repair manual.

Any assistance would be greatly appreciated.