10-16-2025, 10:23 PM
The MEC Legacy and Heff-T-Herman Origins
MEC Aerial Work Platforms, founded in the 1970s, has produced a wide range of scissor lifts and boom lifts for industrial and construction use. Some of their earliest units were manufactured under the Heff-T-Herman name, a lesser-known brand that contributed to MEC’s early growth before the company consolidated its identity. These older lifts were built with simplicity and durability in mind, often featuring direct hydraulic actuation, mechanical limit switches, and steel-framed platforms. While newer MEC models include side-mounted battery trays and digital diagnostics, older units can be challenging to service—especially when decals and model numbers are missing.
Symptoms of Electrical Failure and Initial Observations
A recently acquired MEC scissor lift, repainted and stripped of all decals, showed signs of electrical activity but failed to operate. When switches were activated, audible clicks and relay sounds were present, but the hydraulic pump motor did not engage. This suggests that the control circuit is partially functional, but the power delivery to the motor is interrupted.
The most likely cause is battery failure or insufficient voltage, a common issue in machines that have sat idle for extended periods. However, the complication arises from the battery compartment being located beneath the scissor stack, which cannot be raised without hydraulic power. This creates a paradox: the lift needs battery power to raise, but the batteries are inaccessible until the lift is raised.
Understanding Safety Lockout and Platform Access
Older MEC lifts include a mechanical lockout bar that must be installed before working beneath the raised platform. This bar prevents accidental collapse during maintenance. However, installing the bar requires the platform to be elevated—a task impossible without functioning hydraulics.
To safely access the battery compartment:
Battery Testing and Replacement Strategy
Once accessible, test each battery using a multimeter. A healthy 12V battery should read at least 12.6 volts at rest. If voltage drops below 11.8 volts, the battery is likely sulfated or internally shorted. Replace all batteries as a set to ensure balanced charging and discharge.
Recommended battery specs:
Troubleshooting the Pump Motor and Controls
If new batteries are installed and the pump still fails to engage:
Conclusion
Reviving an old MEC scissor lift requires patience, creativity, and a solid understanding of hydraulic and electrical systems. The hidden battery compartment beneath the scissor stack presents a unique challenge, but with safe lifting techniques and methodical diagnostics, the machine can be brought back to life. These vintage lifts may lack modern features, but their mechanical simplicity makes them surprisingly resilient—and worth restoring for light-duty use.
MEC Aerial Work Platforms, founded in the 1970s, has produced a wide range of scissor lifts and boom lifts for industrial and construction use. Some of their earliest units were manufactured under the Heff-T-Herman name, a lesser-known brand that contributed to MEC’s early growth before the company consolidated its identity. These older lifts were built with simplicity and durability in mind, often featuring direct hydraulic actuation, mechanical limit switches, and steel-framed platforms. While newer MEC models include side-mounted battery trays and digital diagnostics, older units can be challenging to service—especially when decals and model numbers are missing.
Symptoms of Electrical Failure and Initial Observations
A recently acquired MEC scissor lift, repainted and stripped of all decals, showed signs of electrical activity but failed to operate. When switches were activated, audible clicks and relay sounds were present, but the hydraulic pump motor did not engage. This suggests that the control circuit is partially functional, but the power delivery to the motor is interrupted.
The most likely cause is battery failure or insufficient voltage, a common issue in machines that have sat idle for extended periods. However, the complication arises from the battery compartment being located beneath the scissor stack, which cannot be raised without hydraulic power. This creates a paradox: the lift needs battery power to raise, but the batteries are inaccessible until the lift is raised.
Understanding Safety Lockout and Platform Access
Older MEC lifts include a mechanical lockout bar that must be installed before working beneath the raised platform. This bar prevents accidental collapse during maintenance. However, installing the bar requires the platform to be elevated—a task impossible without functioning hydraulics.
To safely access the battery compartment:
- Use a manual hydraulic pump or external power source to temporarily energize the lift system.
- If equipped, locate the emergency hand pump often found near the base frame.
- Disconnect the hydraulic lines from the pump and use a portable hydraulic power unit to raise the platform.
- Once elevated, install the lockout bar securely before proceeding with battery inspection.
Battery Testing and Replacement Strategy
Once accessible, test each battery using a multimeter. A healthy 12V battery should read at least 12.6 volts at rest. If voltage drops below 11.8 volts, the battery is likely sulfated or internally shorted. Replace all batteries as a set to ensure balanced charging and discharge.
Recommended battery specs:
- Deep-cycle 12V AGM or flooded lead-acid
- Minimum 100Ah capacity
- Group size varies by tray dimensions
Troubleshooting the Pump Motor and Controls
If new batteries are installed and the pump still fails to engage:
- Test the motor solenoid for continuity and voltage drop
- Inspect the key switch and joystick wiring for loose connections
- Verify that the limit switches on the scissor arms are not stuck or misaligned
- Check for hydraulic fluid level and filter condition
Conclusion
Reviving an old MEC scissor lift requires patience, creativity, and a solid understanding of hydraulic and electrical systems. The hidden battery compartment beneath the scissor stack presents a unique challenge, but with safe lifting techniques and methodical diagnostics, the machine can be brought back to life. These vintage lifts may lack modern features, but their mechanical simplicity makes them surprisingly resilient—and worth restoring for light-duty use.
