CARRIER 4912729 - Caterpillar

Engage the parking brake, stop the engine and release all hydraulic pressure from the machine. Slowly, lower the bucket to the ground. Move the hydraulic control levers back and forth. Engage the brake pedal again and again to release the pressure in the accumulator.
1. Put marks of identification on the hose assembly connections at the pressure reducing valve (1).2. Disconnect the hose assemblies at valve (1). Put covers for protection in the fitting openings.3. Remove valve (1) from the bracket.4. Install valve (1) on the bracket.5. Remove the covers for protection and connect the hose assemblies to valve (1).6. Make adjustment to valve (1) as given in TESTING AND ADJUSTING.Disassemble Pressure Reducing Valve
Start By:a. remove pressure reducing valve 1. Remove plug (1). Remove O-ring seal (5) from the plug. Remove ball (2), spring retainer (6), spring (3), spring retainer (4) and ball (7) from the valve body. 2. Remove valve spool (8) and spring (9) from the valve body.Assemble Pressure Reducing Valve
1. Install spring (1) and valve spool (2) in the valve body. 2. Install ball (3), spring retainer (6), spring (4), spring retainer (7) and ball (5) in the valve body.3. Install a new O-ring seal (8) on plug (9), then install the plug in the valve body.End By:a. install pressure reducing valve