Cummins ISX 7CEX emits white smoke, smelling coolant, then another day not?

[ichudov]

Rawze, thanks a lot. I will try to open up those things to look for wetness.

Any idea if the fact that it does not emit coolant smoke all the time, is suggestive of any specific hypothesis. I noticed that just after starting cold, it did not seem to smoke white quite as bad. But after I ran it the first day for maybe 20 minutes, and drove it, it smoked white a lot.

The coolant overflow tank also does not bubble.

Also, at least at idle, there is not that much blowby.