Originally Posted by Mr_D
Here's what Cummins said when I sent them an email regarding this:From the perspective of the
Cummins engine it is good to do either one of two things:
1) Start the engine and drive it or 2) do not start the engine.
Our engines do not gain anything by idling. In fact a diesel engine
on low idle will not ever get up to operating temperatures which is
bad for the engine and can cause an increase in soot production.
The other side of the story is that starting the engine and letting it
idle is probably good for other things like air brakes, heating and
cooling, etc. So probably the best answer to try to get both worlds
to meet is to occasionally take the unit out for a drive during times
of prolonged storage."
So Cummins says don't start it unless you plan on driving it like you stole it. I wonder what Onan has to say about this. Conventional wisdom is run the genny, which is also diesel, under load at least monthly thru the cold months. But a genny idles for a living. They never really get much above idle. Hmmmmmm... diesel-diesel, idle/don't idle.. arggghhh