Dave
Have you tried looking at the plugs to see if there is evidence of any specific cylinders oiling more then others? (
With them all blowing 20-25% it seems likely they are all oiling somewhat evenly...) It seems really odd that everything has started to go at once.
The only things that I can think of that would cause a failure across all the cylinders is:
- 'Old age' (which doesn't seem likely unless the parts were used)
- Bad air filtration (which will kill an engine in a hurry)
- A carbon build up problem
- Defective/substandard parts.
- Bad valve seals (or guides)
If there was a sizable leak in the air cleaners it could wear out the rings, cylinders, and pistons in a hurry. I've seen how you maintain your car so I could only imagine this as a possibility if the air cleaner housings fit badly and you didn't realize it. I would also expect it to be worse on one side of another because of the separate air filters. (Check the plugs, but you said 20-25% so I'm assuming that it is all of them)
Carbon could mess up the ring's seal in the piston and that would cause all sorts of oiling problems. The rings actually seal by having the combustion pressure push down on the top of them so the bottom of the ring is sealed to the bottom of the ring groove. This allows the pressure from above to go into the groove across the top of the ring to the back of the groove behind the ring and press on the back side of the ring. This pressure causes the ring to seal against the cylinder wall. The addition of carbon buildup can cause this interaction to fail and this could definitely cause oiling and blowby.
I'm not sure of any methods to check this or remove this kind of carbon buildup. The 'coke bottle full of water' trick is meant to deal with carbon in the combustion chamber so I don't think it would work here. I wonder if an old fashioned water injection kit would help clear up this kind of problem...
Defective parts really means the same thing as old worn out parts. You have to tear it down to see and the only solution is replacing them. It would be nice to know before you do something drastic though.
I can't see it as a valve guide problem with the leakdown evidence you have but if it isn't a cylinder problem perhaps there is a valve seal problem. The smoke seems to really only come when you are running steady state which can build a little vacuum while throwing oil around a bit more vigorously around the valves. This would have to be an intake valve problem so I would also expect to see a consistent puff of smoke on startup after sitting for a bit.
Having followed you down the freeway it would be real nice if you could knock this problem down. It can get a bit hard on the lungs behind you.
