Usage:
HH45 (2JZ),
HH55 (3MZ),
HH65 (4RZ),
HH75 (5WZ) Harvester Heads
Reference: Service Manual Module, RENR3005, Testing and Adjusting, HH45, HH55, HH65 and HH75 Harvester Head; Pages 9-11, "Main Relief Valve - Test and Adjust (Tree Harvester Attachment)". This module is found in Service Manual, RENR3000, HH45, HH55, HH65, and HH75 Harvester Heads.
In Service Manual Module, RENR3005, on Page 10, replace Steps 5-8 with the following:
5. To adjust the main relief valve on an HH45, HH55, or HH65 perform Step 6. To adjust the main relief valve on an HH75 perform Step 7.
6. HH45, HH55, HH65:
Illustration 3. Adjustment Location for the Main Relief Valve (6) Adjustment screw.
a. Turn adjustment screw (6) completely in the clockwise direction in order to adjust the main relief valve to the maximum pressure setting. Do not force the adjustment screw.
b. Install the steering frame lock. Block the wheels. Start the engine. Press the "Terrain/Neutral/Road" switch to activate the "Terrain" mode. Turn the engine speed dial until the engine speed is approximately 1300 rpm. Turn the attachment switch to the ON position.
c. Press and hold the switch to lower the machine. Allow the machine to fully lower. The pump will stroke to the pressure cutoff setting. Hold the switch while the main relief valve and the high pressure cutoff valve are adjusted.
d. Turn the adjustment screw for the high pressure cutoff valve on the implement pump until the pressure gauge indicates 28000 kPa (4000 psi).
NOTE: Lower the pressure setting of the high pressure cutoff valve immediately after setting the pressure of the main relief valve.
e. Turn adjustment screw (6) in the counterclockwise direction until you hear oil flow through the main relief valve. The pressure setting of the main relief valve is now 28000 kPa (4000 psi).
f. Turn the adjustment screw for the high pressure cutoff valve until the pressure gauge indicates 25000 kPa (3625 psi).
g. Release the switch for lowering the machine. Press the "Terrain/Neutral/Road" switch to activate the "Neutral" mode. Turn the attachment switch to the OFF position. Stop the engine.
7. HH75:
Illustration 4.
Section View of the Main Relief Valve
a. Remove plug (7) from the main relief valve with an 8 mm wrench.
Illustration 5.
Section View of the Main Relief Valve
b. With a 3 mm wrench, turn adjustment screw (9) fully in the clockwise direction in order to adjust the main relief valve to the maximum pressure setting. Do not force the adjustment screw.
c. Install the steering frame lock. Block the wheels. Start the engine. Press the "Terrain/Neutral/Road" switch to activate the "Terrain" mode. Turn the engine speed dial until the engine speed is approximately 1300 rpm. Turn the attachment switch to the ON position.
d. Press and hold the switch to lower the machine. Allow the machine to fully lower. The pump will stroke to the pressure cutoff setting. Hold the switch while the main relief valve and the high pressure cutoff valve are adjusted.
e. Turn the adjustment screw for the high pressure cutoff valve on the implement pump until the pressure gauge indicates 28500 kPa (4130 psi).
f. Turn adjustment screw (9) in the counterclockwise direction until you hear oil flow through the main relief valve. Release the switch for lowering the machine.
g. Turn locknut (8) in the clockwise direction until the locknut contacts adjusting screw (9).
h. Tighten adjusting screw (9) in the counterclockwise direction to 3 N·m (27 lb in). The pressure setting of the main relief valve will reduce to 28000 kPa (4060 psi).
I. Install plug (7). Tighten the plug to 35 N·m (26 lb ft).
J. Press the switch in order to lower the machine. The pump will again stroke to the pressure cutoff setting. Turn the adjustment screw for the high pressure cutoff valve until the pressure gauge indicates 25000 kPa (3625 psi).
K . Release the switch for lowering the machine. Press the "Terrain/Neutral/Road" switch to activate the "Neutral" mode. Turn the attachment switch to the OFF position. Stop the engine.
8. Remove the pressure gauge. Remove the adapter (if installed). Reinstall cap (4). Reinstall the valve cover.