I have two diesels. When I start either of them the volt meter reads 12.x volts. then some time after ideling the engine makes some sounds like it is doing something and the volt meter reads 14.x. My powerstroke actually chokes and dies some times during this change over. It seemes to me like the alternater turns on after a warm up period.

Can someone tell me what the engine is doing?

 

the altenator is running at all times the engine is running I suspect that the glow plugs a cycling until there is sufficent heat in the engine as mine does the glow plugs pull alot of volts during this process

 

I thought the glowplugs were only on during the initial firing up of the engine and only for a few seconds at that. That once the engine was going, cold hot or otherwise, the glow plugs shut off. Was I wrong?

 

If the diesel is "cold" then the glow plugs with flicker on/off to keep engine running, mine does it all the time.