My hydraulic pump was leaking oil from the gear/engine-drive connection, so I decided to remove the pump. PO failed to install any gasket there at all so it was an easy fix, but the prime was lost in the pump when it was reinstalled and on reading the archives I tried to fiddle with the pipe-plug on top and blow air into the dipstick hole---both of which only got the pump to judder the lift slowly up. The real fix came by jacking up the rear end high---so that it was above the front, and running it for awhile while I raised and lowered the lift---after about 10 minutes it was smooth as silk. Question: what's happening inside that's priming the pump?
Just curious...