"No special tools required, un
"No special tools required, unless you are planning to tear into the upper or lower gear assemblies. You can split them to change the pump impeller without special tools. Removing the gimbal bearing is much easier with a slide hammer.
You can change the U joints with the upper unit assembled, but it is much easier with the input shaft/bearing/gear assembly removed. This does require a special wrench to remove the backing nut, which you can likely borrow from your local friendly boat mechanic. I recommend you procure a spare "C" clip with the new U Joints, as they can break very easily. The voice of sad experience talking.
Note carefully the order of the shims you find where the bearing assembly fits into the housing, and reassemble exactly the same way. Also the backing nut must be torqued exactly to spec to properly preload the bearing pack. This will also give you an opportunity to inspect the drive and driven gears for any kind of strange wear pattern. If it's a 1.62 ratio drive, the gear teeth must be aligned using match marks during reassembly. Other ratios do not need alignment.
You should get the manual for the drive if you don't already have it.
Rod"