Oil in exhaust system

[Herb_911_76]

An insane amount of smoke at start up led me discover that oil was collecting in the exhaust part of the left bank heat exchanger. I guess it burns off eventually, because the smoking subsides after a while. With the heat exchanger removed, I can see that the exhaust valve seal of C 2 must be bad as oil squirts on the floor when I crank the engine. I think oil seeps past it when I park it while hot, but stops leaking when cold. I proceeded to remove the the lower valve cover and oil started to pour out by the gallons. I can't imagine that this is normal, on the other hand, the oil tank sits higher and what would keep the oil from flowing from the tank to the lowest point? Any input will be appreciated!

[DRACO A5OG]

Wow, if you are seeing oil squirt out of exhaust ports when you hand crank, it is pretty telling of leaking valve seals or piston rings not sealing due to wear or clogged oil return holes on the pistons

Removing covers will drop about 1.5-1.75 quarts of oil from my last valve check with engine in and oil filled. Gallons? That does not sound right at all since the crank only hold about 4 quarts.

[Herb_911_76]

Thanks for your reply. Yeah definitely more than a couple of quarts, it kept on coming after I cracked the valve cover. Eventually I opened the drain plug on the aux tank and only maybe half a quart was left at that point. If the crank holds a gallon (most of which would still be there as it sits lower than the valve header), then the roughly one gallon drained from the valve header. I guess that's about right, so it wasn't gallons, but it felt like it.

No shavings on the magnetic oil drain plug and oil looked pretty decent, so I am hoping for a valve seal. I am a weekend warrior, so I won't get back to it until Saturday.

I am still trying to figure out what keeps the oil from draining from the tank into the crank and I guess eventually overflow the oil return tubes to fill the valve headers. Is there a check valve in the oil pump or is the pump supposed to be that tight? She has been sitting since last summer since I have been working on interior and now in the process of replacing cracked filterbox.
I feel that the excess oil is something I should not ignore. On the other hand once the motor runs, wouldn't the oil pump take care of excess oil? I know I am rambling, but I have no clue how this is supposed to work or if I even have a problem (apart from valve seals of course).

[Trakrat]

Well... my 2 cents....
I recently discovered I leaked some oil on cylinders 2 and 3 when I would turn the crank.
It was less than a teaspoon in amount really, but nonetheless it came out. But it seems the left side collects more oil in the exhaust ports than the right side, as my right side is completely dry and not black at all (more powder white in color)....

However, I never had any amount of smoke during start up... and no indication of oil being burnt onto the headers... I'm guessing I have a small amount of oil that it would burn up before reaching the headers.

Let me know what you find out and if you DO end up dropping the engine to replace the valves, post up some pics of how it looks or what you find was the cause for the leaky exhaust valves.