I know there could be a release lever, but not that I am aware of. My assumption is that since it has a hi/low/neutral range, that neutral is used as a release lever. The thought that this could be broken crossed my mind, but externally the gear selector is working fine and I can tell the difference between neutral and putting it in gear.
There is a relief valve it seems. Looking at the manual it is internal in the Hydro, so not easily accessible. It consists of a ball and a spring, held in place by a screw in plug or set screw. Seems hard to imagine that coming out but anything is possible.
There is a relief valve it seems. Looking at the manual it is internal in the Hydro, so not easily accessible. It consists of a ball and a spring, held in place by a screw in plug or set screw. Seems hard to imagine that coming out but anything is possible.