Smoky Detroit Diesel

[Hatteras 1]

I have two 6/71 N's in my Hatteras 43. The Stb. motor blows a fair amount of blue/grey smoke on starting up, if I rev it at about 1000 rpm for about 3 to 5 minutes or until it is warm it comes good.

The Port motor is fine and our temperature here in winter does not get below about 10C or 50F, in winter they are both slow starters but in summer you only have to point the key at them. Any clue's?

[saltshaker]

try moving this to the tech section

[robymayway]

I have the same problem here in Italy when temperature arrived under 10 ° centigrade ( I dont' know How many F° )
after 1 minutes all is clear .
When I go out at 2000rpm there are no smoke.

[Jaxfishgyd]

DieselKleen fixed my problem. Both 6-71N's would smoke in the winter time (for here, anything under 60 is winter). Both would smoke HEAVY for about 2 mins.

I added DieselKleen and now it's under 15 secs...And not a heavy smoke at that....