Start after rebuild- Lots of white smoke HELP!!

[mmasse]

I just finish the rebuil and started the engine following the procedure on Wayne's book

The plan was to let it idle at 2000RPM for 20 min, but there is a LOT of white smoke coming of the exhaust, so I turned it off after 5 min

Is this normal or is there a major screw up somewhere?...

Thanks in advance for ypu help on this

[E Sully]

Mine smoked a lot on the 20 minute run. It started as the exhaust heated up and the old oil in the exhaust started to burn off. It cleared up a lot towards the end of the run. The engine was tight as a drum after I finished breaking it in.
Check over the engine, pull the plugs to see if all the cylinders are running clean, then run it again. If it doesn't clear up a lot by the end of the run you could do a leak down test to see if the rings are seating.

And always have fire extinguishers.

[mmasse]

Ok, I let it run for 20 min, and I had the impression the amount of white smoke had gone down significantly. So I changed the oil and got ready to go for the first drive, as per Waynes book instructions. But, the engine started throwing a lot of white smoke again. I run it a couple of blocks and back home. Let it idle at 2000RPM for 5 more minutes and the white smoke would not stop.

I took the exhaust and headers out and it looks that Cyl 6 is the one throwing oil. So, I decided to perform a leak down test.
I tested the three cylinders on bank 2 (cyl 4-6). I got pretty consistent leak numbers. 18% on cyl 1; 15% on Cyl 5 and 19% on Cyl 6. On all of them you can hear a bit of air going to the crankcase. No noise on the intake of exhaust sides.
I was surprised to see such high numbers on an engine with new rings, but I thought it might be that the rings are not seated yet.
What confussed me is that Cyl 6 which is the one which seems to be throwing oil (wet exhaust oulet and manifold) did not show any difference with the other cylinders.

Can anyone suggest how to go from here, before the obvious "take everything apart again!!" ?

thanks in advance

[gsxrken]

Did you make sure to stagger your ring gaps on each cylinder?

[mmasse]

Yes, i did.
I pointed the gap of the oil scraper ring towards the top of the cylinder and each of the other ring gaps opposite to each other

[Ronnie's.930]

If it were mine, I would go out and drive the thing at varying RPMs and loads and see what happens regarding the smoke . . . 25 mins of no-load run time is not going to seat the rings.

[JFairman]

..and you can do that at night so the smoke cloud isn't as embarressing.

[E Sully]

What kind of cylinder prep did you do for the new rings? Were the factory honing marks visible?

[mmasse]

here you can see a video of the engine running. You will notice at there is no smoke coming initialy, but after 25-30 second is starts coming out.

http://youtu.be/j2IGW0uM-T0

Let me know what you think

Thanks

[Ronnie's.930]

The youtube link you posted goes to a login page . . .

[mmasse]

link fixed...Sorry!!

Porsche 911 Start up after rebuild - YouTube