Smoke

Blue smoke or black smoke?

Our 85 765T was doing that sort of thing, but worse. After a few seconds of idling it smoked (blue smoke) and it continued until I had been moving about half a minute. The crankcase ventilation was at fault - crankcase pressure was building up at idle and causing oil to back up in the turbo drain, which spilled over into the exhaust. It must have been pooling there, which would explain why it took a while to stop smoking once I got moving. It would also explain the huge puff of smoke. That would be unusual if it were valve seals, because the hotter manifold area wouldn't allow much pooling. Valve seal smoking tends to be immediate; they don't fit the "smoke at prolonged idle, clears when moving" pattern very well.

Cleaning the crankcase ventilation system - I had to replace one hose that was packed with deposits, and wished I had a replacement oil separator available - cured the smoking.

But now you have a nice, new turbo - 300000km is a full life for any turbo.

Mike

Its blue almost white...

I **suggest** that valve guide seals **might** be the problem. A