My friend took her 02 reg Volvo V50 turbo diesel into a branch of a national chain of repairers for a service. It was booked in over the Internet and included, as a special offer, an engine flush. The car has covered 80k miles and has not had a replacement turbo during the time my friend has owned the vehicle, i.e. the last 30k miles, if at all. The car was largely used on short runs with only the occasional motorway trip so sludge build-up was a certainty. Apparently, the engine, after being flushed and filled with new oil, started to rev at high speed and "filled the repairers garage with smoke". The technicians stopped the engine by putting it in gear (it is a manual gearbox), but the turbo has "broken". The issue of overfilling diesels with oil and the implications thereof was discussed with the garage but, although they are prepared to be helpful, they do not consider it to be their liability. They state that the sump oil was added using some technology that I cannot recall and that the level was checked before the engine was started. That the sump oil was drawn into the engine combustion chambers is beyond doubt. Whether worn/aged oil seals broke down once the sludge of 80k miles was removed is a possibility. There is no loss of coolant or any other indication to suggest that the head gasket has blown. At this stage, the injectors have not been removed so a compression test has not been done. Have you any other ideas as to cause and culpability?