Performance Tests
Personal injury can result from hydraulic oil pressure and hot oil. Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system. Make sure all of the attachments have been lowered, oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand. |
The travel pedals control the direction of travel of the machine and the speed of the machine. The IQAN uses electrical input from the pedals in order to control the hydrostatic drive system. Hydraulic fluid activates the swashplate of the power train pump. The angle of the swashplate controls the volume and direction of fluid displaced into the system. The servo piston controls the angle of the swashplate. The pump control, by varying the pressure at the servo piston, controls the position of the piston. An electric signal to the control coils transmits the command from the operator to the pump. Mechanical feedback of the swashplate position to the control through the feedback pins allows for precise displacement control and increases overall system stability
The power train pump is equipped with a charge pump. The charge pump has a relief valve. If the relief valve pressure setting is too low, the performance of the machine will decrease. If the relief valve pressure setting is too high, the life of the hoses and the components will decrease. Performance problems can also result if the relief valve pressure setting is too high.
Problem:
The hydrostatic pumps make noise. The machine does not move smoothly and there are air bubbles in the oil.
Possible Causes:
- The hydraulic oil level is low.
- The viscosity of the hydraulic oil is incorrect.
- There is an air leak on the suction side of the pump.
Problem:
The output of the hydrostatic drive pump is low.
Possible Causes:
- The oil level is low.
- The viscosity of the hydraulic oil is incorrect.
- The charge relief valve to the power train pump is not set to the correct specifications.
- There is a malfunction in the valve for the travel control valve.
- The power train pump has too much wear.
- The propel pump crossover relief valves may not be properly tightened to specification.
Problem:
The machine will not move.
Possible Causes:
- The hydraulic tank is low on oil.
- An electrical system problem may exist. Check the IQAN Monitoring System for any fault codes.
- Check the drive coupling for the power train pump.
- The system is over the normal voltage. The voltage of the system is above 32 V. The system turns off all directional solenoids.
- The system voltage is below 21 V. If the voltage is below 21 V, the ECM will maintain any directional solenoid in ON position. If a new solenoid is turned on, all directional solenoids will be turned off.
- The switch for the parking brake failed.
Problem:
The machine will not start to move until the engine speed is high.
Possible Causes:
- The charge relief valve to the power train pump is not set to the correct specifications.
Problem:
The machine has low performance.
Possible Causes:
- The high idle of the engine is not set to the correct specifications.
- Engine power is low.
- The viscosity of the hydraulic oil is incorrect.
- The specification for the motor displacement is not set correctly.
- There are fluctuations in the drive pressure.
Problem:
The machine does not attain the maximum speed.
Possible Causes:
- The parking brake is misadjusted.
- The adjustment for the minimum displacement on the motors is not set to the correct specifications.
- There is excessive resistance in the final drives.
- The motor displacement control is faulty.
- Low machine voltage. The alternator strap has a poor ground.
Problem:
The machine cannot achieve maximum runout speed in the slow speed.
Possible Causes:
- The maximum displacement control adjustment screw for the stop of the motor is incorrectly adjusted.
- The motor displacement control is faulty.
- The pin with the throttling slots for the motor is damaged or the pin is incorrectly assembled.
Problem:
The performance of the machine is off in one direction only.
Possible Causes:
- The propel pump hydraulic zero setting is incorrectly adjusted.
- The pressure override adjustment that is on the propel pump may be incorrectly adjusted.
- The sleeve of the hydrostatic pump is worn.