So it seems as though I'm caught in a kind of "Catch-22" situation: I need the hydraulic rams to "pop" the outdrive loose, yet the reason I'm trying to get the outdrive off is to access the leaking hydraulic lines behind the gimbal housing!! It appears that the hydraulic fluid leaks out faster than it can generate enough hydraulic pressure to "pop" the outdrive loose.
I've tried trimming the drive all the way down, against the ground, and then cranking the front of the trailer up. But, again, the hydraulic fluid seems to leak out faster than I can crank the trailer up, thereby allowing the outdrive to merely tilt up.
As some of you have suggested, it's entirely possible that the gimbal bearing is corroded to the driveshaft. I am wondering: Would it be reasonable to try to "break" the engine loose first? In other words, using an engine hoist, lift the engine slightly to break the bearing-driveshaft corrosion, then lower the engine back in place so I can use the hydraulic rams to "finish the job?
Another alternative that I'm considering is renting/buying some sort of small hydraulic "pry/spreader" and using that to apply the same force that my rams would normally be able to generate. I'm not specifically aware of such a device, but I assume there may be something out there.
Hope all you dads are having a fantastic Father's Day!!