Port relief......................................................................5

Adjustment procedures ___________________________________________

Port relief valve adjustment

Port relief valves are functional when operating the circuit in which they are installed. As the particular function is activated and the pressure reaches the adjusted setting, the port relief will relieve excessive pressure to the tank cavity within the valve bank, preventing damage to the circuit.

WARNING! Always allow function to bottom out and stop moving before adjusting any pressure.

If the correct pressure reading is not obtained as noted in Items 1 through 5 below, the port relief for that function must be adjusted. The adjustment procedure for each port relief is the same and is:

 Remove the protective cap on the port relief and loosen the nut on the adjusting screw.

 Turn the port relief screw in (clockwise) to increase pressure and out (counter-clockwise) to decrease pressure.

 Once the correct pressure reading is obtained, return the function to the neutral position, hold the screw in place, and tighten the lock nut. Check the pressure reading to ensure that the screw did not turn while the lock nut was being tightened.

Pressure readings:

1. Stabilizer shoe port relief

 Activate the stabilizer shoe raise circuit to fully raise the stabilizer shoe. The main control valve pressure gauge should read 1,200 psi.

 Activate the stabilizer shoe lower circuit to fully lower the stabilizer shoe. The main control valve pressure gauge should read 2,500 psi.

2. Cutter head port relief

 Activate the cutter head raise circuit to fully raise the cutter head. The main control pressure gauge should read 2,800 psi.

 Activate the cutter head lower circuit to fully lower the cutter head and raise the front of the machine off the ground. The main control pressure gauge should read 2,800 psi. Note that you must push in on the selector valve of the anti-chatter/ maintenance valve to get full reading.

WARNING! Keep body parts clear of machine while in raised position or serious injury could result.

___________________________________________Adjustment procedures

3. Conveyor raise/lower port relief

 Activate the conveyor raise circuit to fully raise the conveyor. The main control valve pressure gauge should read 1,800 psi.

 Activate the conveyor lower circuit to fully lower the conveyor. The main control valve pressure gauge should read 1,400 psi.

Note: Be sure that the ball valve is closed on the tank oil fill part of this circuit.

4. Conveyor swing port relief

 Activate the conveyor swing left circuit to fully swing the conveyor to the left. The main control valve pressure gauge should read 1,800 psi.

 Activate the conveyor swing right circuit to fully swing the conveyor to the right. The main control valve pressure gauge should read 1,800 psi.

5. Gathering head port relief

 Activate the gathering head raise circuit to fully raise the gathering head. The main control valve pressure gauge should read 1,700 psi.

 If 1,700 psi is not obtainable, check that the relief in the gathering head float valve that is stamped “CR” is set to 1,800 psi (see Gathering head raise/hold/float-lower circuit in the Hydraulic section of this chapter).