I tried starting my 3GM30F a few times over past couple of weeks and it would not start. The weather has been cold. As far as I can tell, this engine does not have glow plugs or pre-heater (if that is the right term); there is no switch or counter-clockwise movement of ignition key. Batteries tested at just above 12V and I also tried after charging to greater than 12.3V as well as using 'start/50amp' position on charger. Starter was rebuilt about 2 months ago. When I turn key, engine does a turn or two then nothing. Am I out of luck on cold mornings, am I missing something or is there something wrong? thank you, Bob Pilgrim