:thumbup: keep up the good work billie bob , it`s highly entertaining .

FWIW, If the valve stem seals are shot a crankcase vent catch can will do nothing toward resolving an oil burn issue.

Sorry I missed all the fun - went to a wedding.
- I would repost my originals but I don't want to take up room on the forum. I think we're already on page 9.
- You have opened my mind to thinking "root cause" and how would I state my case to a panel of engineers, so I'll use my situation to re-evaluate and try to timeline.
- The carbon on the pistons tops (photos taken) I believe was a result of my not taking preventative measures for: (1) fuels - as indicated in BMW TSBs - SI B13 05 06 & SI B13 05 06 (2) The CCV (PCV) system causing oil vapors introduced to the intake air - This issue is well documented on all forums & oil vapor coating the inside of the intake manifold was said to be normal by both BMW & independent repair facilities (which I didn't agree with). It was also said to be normal that these vehicles use oil at a rate of approximately 1 qt. per 1000 miles (again I didn't agree). What is unknown is what effect this carbon may have had on the piston rings.

The Smog Inspection had clues - The HCs were more then double - The visual tail pipe smoke - And the fact that I did not have a check engine light on - In addition, I was producing alot of nice clean water out the tail pipe. Why the plugs did not show signs of carbon but the combustion chamber was loaded with it - I do not know.

My bandaid (as you call it) is no more then what was utilized on the breathers of the old Chevy systems. As you recall, there was a piece of a pad resting in a plastic holder fastened within the air cleaner to filter crankcase gases being recirculated. That plastic holder was actually cupped to hold any oil caught so it may gravity feed back to the valve cover. As long as I have the correct vacuum when my dipstick is pulled - what is the harm?

Why would Corvette spend time and money re-engineering their PCV system if there wasn't a problem?

I also spoke with several professionals at the machine shops who locally perform the cylinder head repairs for our BMW dealers and BMW repair independents. They even had N62 heads on hand. They indicated the older N62s were most often needing guides - If the guides are good (on any head) it still would take a hell of a lot to get a noticeable amount of oil to burn within a combustion chamber. They noted that although it was not a good idea, remember when the old Chevy's used an o-ring as a stem seal?

In my situation - My car quit smoking, passed smog, the HCs moved below Max. allowable, there is ample vacuum when the dipstick is pulled and I don't use excessive oil. And it has never run better.

As for engineers - I have friends, customers and a relative that designs drone plane parts. I should not have profiled the profession as negative - sorry.

I also have water dripping from the tail pipe. What's your explanation for this?

And in your opinion, is it necessary to do the seafoam treatment as you described, or could one get the same results with fuel treatment designed for cleaning carbon from the combustion chamber? I realize it might take several fill ups with several bottles of treatment. But over time could you get the same results?

It's all good.

The water from the exhaust is normal on any vehicle with cats. Its caused by the oxidation of of hydrocarbons into carbon dioxide and water.

Good question. In my opinion (and I don't work for Chev or BMW) all manufacturers are being driven to reduce emissions, as measured over an extended vehicle life (ie, not just at time of sale). This is a good thing. But then, I don't consider the phrase tree-hugger an insult. I think we should leave a better world for our children, and god knows we are screwing it up fast enough.

BMW accomplished this goal with respect to the PCV, and achieved low emissions vehicle ratings, for these engines. At least one of their solutions used a cyclone separator so as to reduce the amount of oil being returned to the intake tract. It worked fine, in general, as long as the vehicle was driven as the BMW engineers anticipated. That meant limited number of short trips, getting the engine hot enough to burn off the condensation every time, etc,. If owners didn't use their vehicles that way, they tended to get plugged CCV systems, and ensuing problems. You can call it a design problem, or a disconnect between the requirements document and customer's expectations, or whatever.

With Chevrolet, I imagine it is exactly the same. They want to reduce the amount of oil going into the intake tract, thus lowering lifecycle emissions. They likely have additional challenges relating to a very high performance engine, with a non-typical duty cycle (lots of them will get low mileage, occasional use, etc). So, they will continue to try new solutions. Good for them.

Sure, we could go back to a simple PCV, and roll back all of our emissions legislation. Why stop there? We could get rid of fuel injection and go back to carburetors. We could bring back distributor caps, rotors, points, and condensors. We could go back to recurving distributors and replacing vacuum advances. We could even get rid of automatic chokes, because ones with cables worked better than the first generation of automatic chokes. So why not throw away PCVs, install a road draft tube, and just spray the oily fumes on the road? Because it is a significant step backwards. Yes, vehicles are more complicated. They are harder to repair. But they are also doing much more than we asked vehicles to do years ago. It is part of the evolution of the automobile. While we marvel at 100 hp per litre, in a reliable engine that is affordable, relatively economical, doesn't require any significant routine maintenance compared to engines of old, etc, we shouldn't be surprised that there are still areas to improve. On this forum, there is so little discussion of annual maintenance and repairs, that if we didn't have the wide tires, tinted windows, and upgraded stereo threads, there would be little to talk about.

Just my $0.02

Agreed, but I would add to this. When the vehicle is warm, it comes out as steam (vapour). When the vehicle is cold, used primarily for short trips, etc, that steam condenses inside the exhaust system, into liquid. Then, when you start it up the next time, it drips out the back. Entirely normal, but it illustrates why vehicles work better when they regularly get good and hot (which gets rid of the liquid), because that condensation that you see out the exhaust (the drips) is the same inside the engine, where it emulsifies with oil and forms a white paste (which is famous for clogging up CCV systems).

Please read my original problem post. I'm not talking the little condensation you would normally see. I'm saying almost enough for a cup of coffee in a 1 hr. period. I don't understand the cold engine, HCs, COs, CO2s, the effects of fuel soaked carbon build up, etc. etc. But remember I live in San Diego - It's like summer year round. Now that my car is "fixed" - I see very little condensation.

The first thing I will do when I run across this problem again in any vehicle:
- Pull spark plugs & look at piston carbon
- If excessive carbon - I'd spray/soak with Sea Foam (because I'm happy with my Sea Foam experience - but use whatever you want - It's your engine)
- I will probably use the Chevron product in my fuel tank from now on with all my vehicles.
- I would spray it thru the intake to clean intake ports/valves

If you're not experiencing any problems - Just use the fuel tank treatment as the BMW SIB indicates and see what happens.

I found an interesting notation while reading the BMW N63 Engine - Technical Training Workbook (Page 20)

Note: If the exhaust system produces blue smoke, it is necessary to check whether the engine is also drawing oil into the combustion chamber through the crankcase breather, which suggest that there is a fault in the area of the crankcase breather. A clear sign of a problem is an oiled up clean-air pipe.