This has been happening for a long time, but seems to be getting worse. Factory -6, while it is running and for several days sitting there is no oil leakage (OK, maybe a few drops). Anything longer and I start to get a puddle under the passenger side of the engine to the point that I place a large foil pan under the car if I won't be starting/driving it for a while. After a couple months I might have 4 quarts of oil in the pan. I know it is from the dry sump backflowing into the engine, but I can't tell where it is leaking. It is missing the heat exchanger because I don't get the burnt oil smell when starting the car.
Thoughts on where might it be leaking and can it be fixed without pulling the engine?
I was thinking about one/both of the oil return tubes, but figured they would leak while it was running.

Rear main seal comes to mind.

I would lift the car off the ground enough to allow you to inspect the area in question. This is where having a lift really is a blessing.

Wipe everything you can reach to get it as clean as possible ... then watch to see where your leak is coming from.

To keep from wasting a lot of time laying under the car, having a good light source and a video camera that has an adjustable rate time-lapse mode aimed at where you think the leak may be coming from would be nice ... then you could review the 'footage' on your PC/laptop, etc. If not successful on the first go-around, you may need to move the camera around to record different areas, or at different angles, to really nail down the actual source.

Good luck

I think that if the oil return tubes were the source, they would leak onto the heat exchangers. I have seen 911’s wet sump past the pulley end crankshaft seal. I have had good luck with the dealer supplied oil filter with the correct check valve not wet sumping.

Charlie

Another place to check would be the oil cooler seals. One of my old 911s developed a bad leak from there, but it was pretty much while the engine was running.

Valve cover? There is an anti siphon valve made to prevent tank from draining but I've never had an issue with my sixes doing what your describing.

Thanks all. I'll poke around some more and see if I can spot something.
Lift? Yeah, it would be nice, but I'll settle for a heated garage right now...

Where might this anti-siphon valve be??

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