Historically, the rear main bearing oil seal has always been a challenge for the engine designer. Ask any modern competitor of a classic or vintage racecar when apart from getting the engine started in the first place, the second most important quest is to keep the oil where it belongs - in the sump and not on the garage floor! Hidden out of sight somewhere between the rearmost main bearing on the crankshaft and the engine flywheel, the zone is rarely awash with oil but neither is it...

In the world of automotive engineering there is a strong belief that unreliability creeps in when humans interfere. Take servicing the engine oil system, for instance. Consisting of a pump, a filter, some bearings and one or two other components - not forgetting, of course, the oil - when assembled under the cleanest of conditions and serviced regularly to the same standards, we can expect the engine to last for the full design life (generally at least 150,000 miles, or 240,000 km) and...