Re: 1965 merc lower unit help!!! Pics
Please clarify, you took the drain plug off the gearcase and no oil came out? The oil is should be in the large buldge around the propshaft where the gears are.
Can you turn the prop shaft at all?
There is quite a few parts inside the gearcase (see pic), and certainly they are prone to seizing if left stored for long periods without lubrication.
The fact that you need to 'pull up' on the driveshaft to turn it, sounds like perhaps the propshaft/bearings are seized or damaged.
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