Engine has around 10 hours and last year over a two week period the oil tank emtptied into the engine. I installed a cut off valve but seems to me that is a pretty bad leak. Short of the crank seals can any other seals cause this?
My cousin's RFI has a inner lip seal leak and it must be pretty bad. I installed a single cut off valve like I usually do and the generally solves the problem. However a single valve did not prevent his ski from locking up after the ski sat for a month or so. I ended up installing a second valve on the return line. That seems to be working. The ski runs great and I'm not about to advocate rebuilding a good engine. My wife's ski has an inner seal leak and after sitting for 10 days it will hydrolock. I installed a valve 4 years ago. That ski sits for a year at a time and starts right up. Smokes a bit much on start up and settles down quickly. I don't have to worry about the bearings not getting enough oil. LOL Good Luck !!
On a side note that was the first engine I rebuilt. I don't think the seals are leaking around the shaft. I didn't use sealant on the perimiter of the seals. That's where I think the leak is. My reason for not using the sealant was that is set up pretty quick and I thought it would be a problem when putting the engine together. I use 518 for that now. I am a firm believer in putting sealant around the outside of the seals.