Troubleshooting Marklift 15 Lift That Won’t Go Up

[MikePhua]

The Marklift 15 is a versatile and commonly used aerial lift that provides easy access to high places for a wide range of tasks, from construction to maintenance. However, like any piece of equipment, it can encounter issues over time. One such issue that operators may face is when the Marklift 15 won’t go up, meaning the lift is unable to raise the platform to its full height. This can be frustrating, especially if the lift is needed to reach elevated work areas. Understanding the potential causes of this issue and the steps to resolve it is crucial for maintaining productivity and ensuring the safety of the operator and those around them.
Understanding the Marklift 15
The Marklift 15, manufactured by Marklift (a subsidiary of Terex), is a popular machine in the aerial work platform category, typically used in industrial, construction, and maintenance applications. It is designed to offer a reliable method of reaching heights of around 15 meters (about 49 feet) with a platform that can carry personnel and tools. These lifts are known for their compact size, making them suitable for navigating narrow spaces and tight job sites.
Equipped with hydraulic systems, the Marklift 15 is capable of vertical movement and rotation for increased versatility. The machine’s lifting mechanism is powered by hydraulic fluid that is controlled through valves and pistons to raise and lower the platform. The machine's functionality relies heavily on the hydraulic system, electrical components, and mechanical parts.
Common Causes of Marklift 15 Not Going Up
If the Marklift 15 lift isn’t going up, it’s often related to one or more of the following issues:

1. Hydraulic System Failure
   The most common reason for a lift not raising is a failure or malfunction within the hydraulic system. This system uses hydraulic fluid to power pistons, which in turn lift the platform. Common issues within the hydraulic system include:
   • Low Hydraulic Fluid: If the hydraulic fluid levels are too low, there won’t be enough pressure to power the lift mechanism.
     
   • Air in the Hydraulic System: Air bubbles in the hydraulic fluid can cause the system to lose its ability to build pressure.
     
   • Damaged Hydraulic Hoses or Leaks: Leaking hydraulic lines or hoses can result in a loss of fluid pressure, preventing the lift from working.
     
   • Faulty Hydraulic Pump: The hydraulic pump is responsible for circulating the fluid under pressure. If it’s malfunctioning, the lift won’t operate properly.
     
   • Blocked or Damaged Valves: The valves that control the flow of hydraulic fluid may become blocked or malfunction, restricting the movement of the platform.
     
2. Electrical System Problems
   A significant portion of the Marklift 15's operation is controlled by electrical components. If there is an issue with the electrical system, it could prevent the lift from raising:
   • Battery Issues: A weak or dead battery may not provide enough power to operate the lift.
     
   • Wiring Problems: Loose or frayed wiring could interrupt the power supply to critical components.
     
   • Faulty Relay or Switches: If the control switch or relay is malfunctioning, it might prevent the lift from responding to user inputs.
     
   • Blown Fuses: Electrical fuses protect circuits from overloading. A blown fuse could stop the lift from working.
     
3. Safety Interlock System
   The Marklift 15 is equipped with safety features designed to protect the operator and machine. If any of these safety systems detect a problem, they will prevent the lift from operating:
   • Emergency Stop Activated: If the emergency stop button has been pressed or activated, the lift will not go up until it is reset.
     
   • Out of Level Warning: Some lifts have an out-of-level safety feature, which prevents the lift from operating if the machine is on uneven ground.
     
   • Operator Presence Detection: Some models have systems that detect the presence of an operator in the basket. If the system does not detect the operator correctly, it might stop the lift from raising.
     
4. Mechanical Problems
   Mechanical failure can also be a contributing factor. Issues with the lifting mechanism, such as a broken or jammed cable, worn-out components, or malfunctioning motors, could prevent the lift from going up:
   • Damaged Lift Arm or Cylinder: If the lifting arm or hydraulic cylinders are damaged, they won’t be able to move the platform.
     
   • Worn Out Bearings or Joints: Over time, bearings or joints in the lift's arm mechanism can wear out, causing movement to become restricted.
     

Steps to Troubleshoot and Resolve the Issue
If your Marklift 15 lift isn’t going up, follow these troubleshooting steps to identify and resolve the problem:

1. Check Hydraulic Fluid Levels
   Start by checking the hydraulic fluid levels. If the fluid is low, top it up with the correct type of hydraulic oil as recommended by the manufacturer. Be sure to inspect for any signs of leaks in the hydraulic hoses or connections. If you find a leak, it will need to be repaired before the lift can operate correctly.
   
2. Inspect for Air in the System
   If there is air in the hydraulic system, it can prevent the lift from raising properly. Bleeding the system may be necessary. This involves opening specific valves and allowing the air to escape while fluid is added. If you are unsure how to perform this, refer to the operator’s manual or contact a professional technician.
   
3. Examine Electrical Components
   • Battery Check: Ensure that the battery is fully charged. If it is low, charge or replace the battery as needed.
     
   • Inspect Wiring and Fuses: Look for any loose or frayed wires and replace any damaged ones. Also, check the fuses to ensure they are intact. A blown fuse can often be the culprit.
     
   • Test the Controls: Verify that the lift’s control switch is functioning properly and that there are no issues with the relay or other electrical components.
     
4. Reset Safety Interlocks
   • Check if the emergency stop button has been engaged, and reset it if necessary.
     
   • Ensure the lift is on level ground and that there are no obstructions or safety warnings preventing it from going up.
     
   • Confirm that the operator presence system is working correctly, and if you have doubts, reset the system or contact a service technician.
     
5. Inspect the Lift Mechanism
   • Visually inspect the lift arm, hydraulic cylinders, and other mechanical components for any visible damage. If any parts are broken, bent, or damaged, they will need to be repaired or replaced.
     
   • Lubricate any moving parts as recommended by the manufacturer to ensure smooth operation.
     
6. Consult the Manual or a Professional
   If none of the above steps resolve the issue, consult the operator’s manual for further troubleshooting steps or contact a professional technician. Some issues, particularly those related to complex hydraulic systems or internal components, may require specialized knowledge or tools to fix.
   

Preventative Maintenance Tips
To avoid encountering similar issues in the future, regular maintenance is essential:

1. Regular Hydraulic Fluid Checks
   Check the hydraulic fluid levels regularly and ensure that the fluid is clean. Replace the fluid at intervals recommended by the manufacturer to prevent clogging and wear of hydraulic components.
   
2. Routine Battery Maintenance
   Keep the battery charged and clean. Inspect for corrosion on the terminals and clean them if necessary.
   
3. Inspect for Leaks
   Periodically inspect hydraulic hoses, connections, and seals for leaks. Promptly repair any leaks to prevent fluid loss and pressure issues.
   
4. Lubricate Moving Parts
   Regularly lubricate all moving parts, including lift arms and joints, to ensure smooth operation and prevent wear.
   

Conclusion
A Marklift 15 lift that won’t go up can be caused by a range of issues, from hydraulic failures and electrical problems to safety interlock triggers and mechanical damage. By following a systematic troubleshooting process, you can often identify the root cause and make the necessary repairs to get the lift functioning again. Regular maintenance and inspections will also help keep the machine in good working condition, reducing the likelihood of future problems. Always refer to the manufacturer’s guidelines and seek professional assistance if you are unable to resolve the issue on your own.