[Egon]

Then there are those who say the most engine wear occurs at start up?

Me, In don't know?

The construction company I used to work for left the equipment running 24/7. The only time it was shut off was for mechanical or specific service work which was scheduled by engine hours. This was on a jobsite that had two ten hour shifts. The company had lots of data and also had good communication with the Caterpillar company!

Me; I don't know. I'm not in access mode to proper data at the moment!

Of course very cold weather operation could be a different animal. Shut the stuff off and it may not start! This is also where Rad shutters and idle speed control come into play.