Re: how long to crank.

I am coming from a W123, but I have cranked it for more than 15 seconds before in the cold (on 3 of 4 GP's) and it started.
I am at the point where I can listed to the noise it makes while turning over to see if its worth continuing. Listen to the sound the engine makes if you hit the starter without letting it glow. Then listen to the engine after a good glow time - the engine sounds "smoother" (like the cylinder is firing but not hard enough to push the engine on its own). If starting is questionable, let it turn over for 5 or 10 seconds, see if the noise it makes changes, if not, then give up, it it starts turning over faster/smoother then keep the starter turning.

You 603 starter may not like this (most people with 240D's put 5cyl starters in them anyway...), but there is a sound that it makes.

I thought that Brian Carleton or someone put up instructions on how to start your diesel in cold weather/low battery/bad GP's and it went something like this-
2 glow cycles, (I do 3 if its quesitonable)
leave the starter turning until the battery dies or the engine starts- once you let up that GP heat has more chance to leave the engine where it is needed.

This is just what I've seen, on an older and smaller motor with fewer cylinders.

-John

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