I usually leave the boat with the outdrive up, but lately have returned after a few days to find it down. It must be a leakback problem of some sort. I looked up the problem in the repair manuals and it seems like a pain in the *** project to mess with it. I sounds like the procedure calls for the boat to be out of the water and system drained and then a lot of springs, balls and valves. I'm wondering if a pump replacement makes more sense. Basically, I'm also wondering if anyone out there ever had this problem, whatr they did and what they recommend.