Just picked up a used Advantage 29 footer with the 525 Mercury Racing engine. Took it out for a spin today. When I got back from a run of about 1/2 hour I opened up the engine hatch and found the drive oil reservoir almost completely empty with drive oil all over the engine and the whole back of the transom. I feel if I had run the engine for another 15 minutes my low oil drive reservoir warning alarm would have gone off. Before taking the boat out I actually topped off the drive oil up to the top level line on the reservoir so what could have caused all the drive oil to be all over the engine compartment? I believe the oil reservoir is a gravity fed system. Please correct me if this is not the case. It almost looks like the tube feeding the outdrive started to reverse flow the drive oil right out of the top of the drive oil reservoir. If this is true what would cause that? I did check and the cap on the top of the reservoir was tight.