Question: Dear Flying Spares team, In order to get rid of occational clouds of blue smoke particularly after warm start of the engine of my Silver Shadow 2 I recently replaced the valve stem seals. When I ran the engine for the first time with the new seals it continuously emitted blue smoke which did not improve even after 10min idle running. It is definitely worse than before.
I purchased the traditional wound, waxed seals from you. I also carefully followed the procedure described in the workshop manual, soaking the grommets in oil before assembly and finally degreasing and sealing the collets with Loctite RTV.
Do these seals require some driving before they develop their full sealing performance?
Is their anything else I could have done wrong when installing the seals?
Should I better have upgraded to the modern rubber spring supported oil seals? 
Thanks for advice and best regards

Answer: Many thanks for your post. I have spoken to our mechanic and the following is what he has said.
As long as these have been fitted properly they should be fine. The later type have less margin for error. There may be some oil that has leaked into the cylinders, this may take time to clear. Run the car for a while keeping an eye on oil pressure. Hopefully this should clear in time. Monitor oil level, if the engine is using oil then a seal may be faulting.

Question: How many hours should be expected for labor when replacing valve stem seals on a 1976 SS? How common is it to have to replace the valves also due to wear (engine had 32,000 miles)? I'm getting smoke after warm start up and sometimes while driving or sitting at a stop light and pulling away.

Answer: As regards the Valve stem seals,they do say approximately 16 hours to replace these. I Have been told that these can fail due to lack of use. As regards the smoke with the car if it is white then this could be a possible head gasket failure.

Question: After several month and about 2000 miles I have to admit that there was no reason to panic.
The traditional seals do a great job. It took about 20 miles of driving until the oil cloud from the exhaust abated visibly and finally disappeared completely. 
Since then there was no oil smoke any more under any conditions.
Also the previously significant oil consumption dropped to unmeasurable.

Answer: I'm glad to hear that you have sorted it.