I picked up a scat trak 520v thats been passed from a few owners due to parts available. I got it home after i made sure it ran and had hydraulic pressure. The swing motor and boom cylinder were missing. After a 6month wait i finally got a swing motor from italy. I havent installed it yet because i need to track down another fitting for it. I have all the lines capped off. It tracks and steers, and the dozer blade works flawlessly, however i have no working cylinders on the boom. I pulled the lines off while its running and its getting hydraulic fluid without engaging the joysticks. Do they work as shut offs? So killing flow in either direction lets them operate?