GregH said:
Main reason being, at idle a diesel burns very little fuel and the engine temps drop below the optimum point. This causes unburned fuel to puddle in the crankcase and contaminate the oil. THis in turn accelerates wear.
When the major makers speak, we should listen.
GregH
Someone should tell this to the applejacks that sit with their diesel idling in front of the doors to the store, while their family shops for 30 mnutes.
I have to wonder about this, Trucks are often left idle overnight, construction equipment often is idle for hours. I worked at the airport when I was young, the diesel equipment was never turned off in the winter, (left idle all night, every night).
Clearly a running engine will wear faster than one that is not running. I'm just wondering about how big a deal is the accelerated wear aspect. Does that mean the engine will only last 300k miles instead of 350k?
There is also a certain amount of wear from a cold start to factor in.
I have an engineer friend, (which is odd because I dislike engineers
), who worked at TRW, on failure analysis of engines. His wife is also a retired petroleum chemist. I am going to see them today, so I will get their opinion on this.
I let my tractor run at idle for 5 minutes to cool down after working it, then I shut it off.