I am posting this for my hubby, so bare with me. I might have no idea what I am talking about! I didn't see a V1100 in the options, but our customer has a 1989 V1100. ( Yes ancient and should be replaced). The lift is super large and moves very heavy tanks.

My husband replaced the brakes. Has air side and hydraulic side. He didnt do the hydraulic side, just the air side. The issue it was having before hand was that the brakes were sticking and the lift wouldnt move at all. It had steering and power, just would go anywhere.

Replaced air side as stated. Bled, replaced breather cup, etc. The lift then moved but wouldnt stop (I think). Tested the hydraulic pump- no pressure. Replaced the hydraulic pump.
Now the lift has pressure if the parking brake is ON ( deadman seat brake interlock bypassed years ago by another mechanic), but has no pressure if you take the parking brake off- so basically, you arent going anywhere.

It tries to move, has full power, has steering.
First idea is the brake interlock system- WHERE would this be on this ancient lift, anyone know?
Second, is that the kidney seals blew.

Anyone ever have this happen? ANY ideas at all no matter how small let me know! He is also calling cat and beating the heads of mechanics there to no avail.