one for james

300 tdi, 154k,since i got it 2 years ago it has belched out tons of blue smoke in the morning and runs rough initially but clears if you rev it hard,does not smoke for the rest of the day if the engines warmed up,i assumed it was the valve stem seals,now i changed the head on sunday for one that did not smoke before i fitted it to mine,so thinking its bore wear,there was light misting on top of the pistons if its not bore wear or stem seals cant think what else would cause it to burn oil,i am not overly concerned but would like to fix this issue if possible

Could it be the engine timing when starting from cold. Mine did something similar (got a vid somewhere) the timing was slightly out. But before I checked it, I changed valve stems seals, skimmed cylinder head, ground the valves, still a load of smoke then check the timing wish I'd done that first.

But I'm not very mechanically minded so you may choose to ignore what i have just wrote.

Did you not see any bore wear while the head was off? Or were you concentrating on the valve stems!

try it with hose off inlet manifold, does it start immediately,as previous said check timing

jamesmartin said:

try it with hose off inlet manifold, does it start immediately,as previous said check timing

Click to expand...

will try that tomorrow,cheers james