I have a big blue 300 with a three cyl Cat that won't start without the glow plugs below 70 degrees. It only has 600 hours on it.

Agreed.  The old  v-12's would pur right along.  I have always been partial to the water cooled gas engines in the older machines, probalbly just a bias I picked up from an old timer that took time to do a lot of teaching.  That being said I have always preferred a diesel in my trucks.

Yes, I worked on a German one recently, it ran fine but wouldn't want to own it. Has a convoluted Bosch electric system I would have been tempted to scrap, a bushel of extra junk, several relays, probably fine when new but these just don't need it.
  The dozer is all USA all super simple. Only thing that would have been better was the C model with wet steer clutches and if I was going to work the crap out of it the 450 which has bigger 4 cyl.
  On some of our tractors I finally throw it all in the dumpster, put on new Nippon 12v starters, delco alt and the 5 wires or so it really needs and done with it. World of difference, night and day, all simple stock stuff.