engine problem 1940 110

Posted by John Miller On 2010/9/26 18:14:31

I am reviving a 1940 110 that was parked for 20 years. The problem that has developed is after 200 miles of driving is that it blows blue smoke when accelerating and when it idles for along time. I have taken the head off and decarbonized the top end. the cylinder walls and pistons look new, the valves look fine. Took of the pan and the bottom is the same, clean!
So that leaves a broken ring, a stuck ring, or a valve not seating.
I think!
Does some one have an idea to isolate the problem before I start to rebuild what appears to be a perfect engine?
The car has 71,000 original miles.
Thanks
John