Clattery when cold
Join Date: Feb 2012
Location: United Kingdom
County: Greater London
The oil consumption thing may not be just luck, but how the engine was treated when new. In the motorcycle world, where specific power outputs are much higher, the conventional wisdom has changed a lot about running in, since whether/how it's done it makes a large difference to the rest of the life of the engine. It used to be that with older, wide-tolerance engineering it was mandatory to run-in progressively, with gradually increasing rev limits over the first 1,000mls. That has changed. Best practice now is (a)to avoid synthetic oils initially, since they actually prevent wearing in of surfaces (b)rev the **** off it pretty much from day#1, although avoid lugging/heavy loads as unkind to bearing shells.
The reasoning behind this is that old school running in, especially with synthetics, encourages the surface of the bore and piston rings to polish each other and quickly become glazed. The result is an engine that forever drinks oil and is somewhat down on power due to blow-by.
Best practice now is fairly hard initial use, with ordinary mineral oils. During this period both bore and rings continuously microweld to each other due to localised friction at high spots, and end up with a permanent slightly rough surface that subsequently retains the oil film much better and seals better, giving more power. Running in is therefore really brief, followed by a change to synthetic once the microscopically rough surfaces have been achieved.
The only downside to this approach is that it may shorten the life of the engine a little, but there are arguments about that.