When the knurled screw is screwed in, the valve opens and oil can flow. To lower
the tail lift the knurled screws are screwed in and the tail lift will drop on its own, i.e.
oil flows out of the cylinder.
Both knurled screws have to be turned at the same time or else the entire load will be
taken by one cylinder. If the platform is empty this is not a problem, but it should be
To stop the lowering process screw the knurled screws back out.
Stop turning the knurled screws out when a light resistance on the screw is felt. The
knurled screws can be screwed all the way out if personnel are not careful.
To extend any pair of cylinders, check none of the knurled screws are screwed in,
operate the correct mushroom button on the tail lift manifold and slowly screw in the
knurled screws on the required left and right cylinders of the tail lift.
If the mushroom button on SV30a or b is RELEASED with the valves screwed in, the tail lift
To stop the cylinders extending screw both the knurled screws out in unison until a
light resistance is felt.
Once complete ensure all knurled screws are screwed out until slight resistance is