I have a gravely zt2760 HD zero turn with a zt 2800 hydro Axle, recently I replaced both charge pump o rings because they were both leaking. After I replaced the o rings the right side worked fine but the left side had zero power. I tried purging it with the bypass valve (I think it's the lever that let's you move it without power), I see bubbles coming out of the left side of the reservoir. But I'm still getting no power. Is there any reason why this is happening? It was working fine before.
On the unit that is not working I suspect that you have the charge pump cover rotated 180 degrees from how it was previously installed. Remove the mounting screws and turn the cover half of a turn and see what happens.
before you rip it apart again lift the wheel off the ground
Set the engine to the lowest speed it will run and do your purging again
Air compresses so if there is a load on the wheel then the pistons can just compress the air and not pump it out .
