@margallar correct me if am wrong..
I think you u should go for a compression test. Perform it, and check whether its only seals or there is some issue with Rings.
Mainly start up smoke is due to Valve Seals. But in my case, start up smoke was there. When i went for compression i got to know that rings are also worn out.(no blue smoke from tail pipe)......
So, its better to check engine thoroughly.