The oil in my /6 has less than an hour of running time. I need to readjust the valves.

Can I pull the lower valve covers without draining the oil? I'd hate to waste perfectly good oil? Not being cheap, just hate to create more contaminated oil.

-Rusty

keep telling yourself that like a few quarts matter in the world

Yes you can.

Put a rag on top of the heater boxes to catch dripping oil and don't waste any time adjusting them. It will slowly drain about 3-4 quarts over time. But, if you start the job to finish it, shouldn't do anything more than soak up a couple of rags a bit. You won't need to worry about the top of course.

If you tilt the car you can get away with it. It probably
varies based on how much oil has drained from the tank
to the sump, which takes a long time.

Thanks, Dan. I guess I might as well just drain it, rather than deal with the mess of 3 quarts on the ground.

-Rusty

Yeah, I remember one time I pulled the covers without draining the oil and walked away because no oil was dripping. BIG mistake. I came back about an hour later to find some 4 quarts of oil all over the garage floor!

If you jack up th car really high on the side you are working on you can do it without too much mess at all. Try wrapping aluminum foil all over the exhaust to keep the oil off of them.
i haven't adjusted valves without draining the oil but i replaced a valve cover gasket with oil in ther engine and only lost a few ounces.

Like root says, oil will gradually flow from the tank to the engine sump over time and can make a mess.
I once pulled a return tube off with the car jacked up on that side. It dripped for a few minutes and then stopped. I watched it for about 10 minutes and decided it was cool.
The next morning I had several quarts on the floor. bad deal. At least my concrete will never rust

You could always drain the oil in to something ultra clean and then pour it back in.