Oil rings generally do not crack, but they sure are known for sticking due to deposits...but not suddenly. Oil in the cylinders, no matter how it got there, will cover up leaky compression rings. In fact, wetting the cylinders and rechecking a low cylinder is a common method for determining whether loss was through rings, or otherwise (valves or head gasket).

Assuming no blocked oil return holes in the head - have you checked to be sure that the crankcase is not overfilled? After that, disconnect the breather and plug the intake and see if there is blowby or oil droplets. That should give enough info to decide if it is crankcase related or internal.

If it seems more likely to be internal, that one cylinder you said runs wettest is probably the source.

I wouldn't think there's any way oil could get into your intake system in a non turbo engine unless it's coming up through the pollution control system. Check the hose fittings on the intake manifold. They get plugged after a while. Maybe disconnect the pollution control tubes while the engine is running to see if alot of oil fumes are coming out. You can try putting a vacuum gauge on the intake manifold to see if the reading is steady. I believe if it jumps aroud alot it would indicate a valve seal problem as one of the reasons. Although it's not the only one.

This sounds like a broken ring. Has the engine overheated recently? It might also be due to incredibly worn intake valve stem seals.
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See the 700/900 FAQ under 'Select Link' button on the top right.

Hello:

It seems like you should do a compression test-- how many km on the engine? How many liters of oil do you need to add between oil changes?

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Herb Goltz, Aurora, Ontario, Canada '92 245 w/130K mi, '92 945T w/200K mi