20539676 Volvo.Penta Pipe, air venting

Sudden movement of the machine or release of oil under pressure could cause injury to persons on or near the machine. To prevent possible injury, do the procedure that follows before testing and adjusting the hydraulic system.
1. Move the machine to a smooth horizontal location. Move away from working machines and personnel. Raise the mainframe. Position the leg safety struts, and lower the mainframe and conveyor to relieve hydraulic pressure in the system.2. Permit only one operator on the machine. Keep all other personnel either away from the machine or in view of the operator.3. Activate the parking brake.4. Stop the engine.5. Move the hydraulic control lever to all positions to release the pressure in the hydraulic system.6. Carefully loosen the filter/breather on the hydraulic tank to release the pressure in the tank.7. Make sure all the hydraulic pressure is released before any fitting, hose or component is loosened, tightened, removed or adjusted.8. Tighten the filter/breather on the hydraulic tank.9. The pressure in the system has now been released and lines or components can be removed.During a diagnosis of the hydraulic system, remember that correct oil flow and pressure are necessary for correct operation. The output of the pump (oil flow) increases with an increase in engine speed (rpm) and decreases when engine speed (rpm) is decreased. Oil pressure is caused by resistance to the flow of oil.Visual checks and measurements are the first step when troubleshooting a possible problem.Visual Checks
A visual inspection of the hydraulic system and its components is the first step when a diagnosis of a problem is made. Make the inspection with the engine off and all hydraulic cylinders lowered to the ground and the parking brake engaged.
Do not check for leaks with your hands. Pin hole (very small) leaks can result in a high velocity oil stream that will be invisible close to the hose. This oil could penetrate the skin and cause personal injury. Use cardboard or paper to locate pin hole leaks.
1. Check the oil level in the hydraulic tank.2. Remove the filter element and check it for material that would give an indication of damage to a component.3. Inspect all lines and connections for damage or leaks.4. Inspect all control linkage for bent, broken or damaged components.Checks During Operation
The checks during operation can be used to find a valve or pump that is not working correctly. The speed of rod movement or the torque on a motor can be used to check the condition of the cylinders, motors and the pumps.1. Feel the cylinders as they extend and retract. Movement must be smooth and regular.2. Listen for noise from the pumps.3. Listen for the sound of the relief valves when they open. Relief pressures that are too low will cause reduced force of all functions and will cause an increase in the operating cycle time of the functions. Opening pressures that are too high will cause a decrease in the service life of hoses, components and structures.4. Be aware of drift rate in machine functions caused by cylinder leakage, control valve O-rings, or valves that do not seat properly.Power Take-Off Clutch Alignment
Make reference to Warning on first page of Troubleshooting.
The power take-off clutch alignment should be checked when the power take-off is first installed, before the power take-off belt bands are installed and the air hose connected. If the alignment of a power take-off clutch already in service must be checked, the power take-off belt bands must be removed to allow free turning of the power take-off shaft.
Checking Parallel Alignment
(1) Drive ring. (2) Flywheel. (3) Power take-off clutch. (4) Dial indicator.1. Check the parallel misalignment between engine flywheel (2) and power take-off clutch (3) by locating dial indicator (4) as shown on power take off clutch (3) and on the outside diameter of drive ring (1).2. Rotate the power take-off shaft through one complete revolution. The dial indicator reading should not exceed 0.23 mm (0.009 in).
Checking Angular Alignment
(1) Drive ring. (2) Flywheel. (3) Power take-off clutch. (4) Dial indicator.1. Check the angular misalignment between engine flywheel (2) and power take-off clutch (3) by locating dial indicator (4) as shown on power take off clutch (3) and on the face of drive ring (1).2. Rotate the power take-off shaft through one complete revolution. The dial indicator reading should not exceed 0.23 mm (0.009 in).Power Take-Off Clutch Clearance
Make reference to Warning on first page of Troubleshooting.
Engagement of the rotor could cause personal injury. Stop the rotor engine (engine A), remove the engine start key for the rotor engine (engine A) and attach a DO NOT OPERATE tag to the control.
The power take-off clutch clearance is the axial distance the pressure plate moves along the output shaft when air pressure is applied to the air tube.
Power Take-Off Clutch Clearance
(1) Drive ring. (2) Clutch pressure plate.1. Remove the inspection cover from the housing. Measure distance (A) between drive ring (1) and clutch pressure plate (2). Record this measurement.2. Check for at least 620 kPa (90 psi) of air pressure. Move the rotor switch to the ON position.3. Measure distance (A) between drive ring (1) and clutch pressure plate (2). Record this measurement.4. Move the rotor switch to the OFF position.5. Subtract the second measurement (step 4) from the first measurement (step 1).6. If the power take-off clearance is 12.70 mm (.500 in) or more, replacement of the clutch friction discs is necessary.7. Install the inspection cover.