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VW ALH : Extreme smoke... on new rebuild

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Faztco:
Hello again: heres my second big problem( besides Glow Plug system): 2001 ALH, full modified rebuild , Bored .5mm , new everything. When start the engine - to me, it smokes far too much for a fresh rebuild. I mean it clouds out the car.. kinda bluish white. The Turbo is fresh and is not internally leaking, engine is not using coolant. I only have about 100 KM driving time, and after engine is intermittantly loaded up on the highway, it doesnt seem to smoke anymore. Yet the next morning I start the engine and again tons of smoke. Am I just not allowing enough Break in time?, I have heard it takes up to 1000 K to Break in these motors. Reason I am alittle worried is because years ago I helped my brother rebuild a 1.6 TD in his Jetta. We fitted the oversize pistons in the newly bored block and they were VERY tight... I mean a thou or two clearance. Fast forward to my rebuild:IGet the block back with overbore and too me the pistons went in with too much clearance... thus the smoke problems I see now. I bet you there was 4-5 Thou on this 1.9 ALH. when the engine is running, it sounds good and there is lots of power on the Highway at 25 Lbs boost. Somebody tell me I`m freaking out for no reason. Car is off the road till the weather gets warmer, and I have a spare Block incase the worst senario - The machine shop Bored the cylinders too large.

libbydiesel:
The spec is 0.001" piston to bore clearance.  You say you got the block bored for your oversize pistons, did you measure the bores afterward?  If there was any doubt about the clearance, that was the time to do it. 

Do you have clear fuel lines before and after the injection pump?  Any air getting into the fuel?  Air in the fuel will cause the exact symptoms you describe and is a lot easier to solve than incorrect bore.  I assume you timed the injection pump using vag-com correct? 

Faztco:
Yes Sir ; I timed with my Vagcom... towards the upper end of the advance scale on the graph . When I brought the Block + box of pistons to the machine shop, unfortunately I didnt check bore size because I trusted the machinest.... after he said that he had to make a call to check Bore. I am SURE that the pistons had far more than .001 Clearance. I guess that I will start stripping down my spare block soon and prepare to have it overbored. Thank you for your help.

Faztco:
...Also: GOOD idea about the Clear Fuel lines, I just ordered some, will post results.... Thank you Sir.

libbydiesel:
I can understand wanting to trust a machinist, but I don't understand installing the pistons, noticing that the clearance is larger than your prior VW diesel rebuild experience, and then simply continuing to finish the build.  I misspoke before - spec for ALH piston to bore clearance is 0.0015.

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