How to Fix an HB Series 2 When It Won't Elevate


When we receive calls about machines, especially the HB-1430 or HB-1030 not elevating, the issue usually has something to do with the pothole plunger being bent. It’s a common wear and tear item that gets overlooked because it’s under the scissor stack.


Here’s how to check your lift’s pothole plunger:

  1. Check to make sure you have 22+ volts DC at terminal block 19 in the lower control panel. If you do have 22 volts DC, you will need a 5–6 in piece of wire to jump power to the up coil.

  2. Place one end of the wire on the white wire with the diode (be sure to place it on the opposite side of the diode, away from the terminal).

  3. Place the other end of the wire on the red wire that comes to the pump solenoid off the battery. This will give you voltage to the up coil that raises your platform in the air.

  4. Hold both wires in the correct position until the platform of the machine is about 5–6 ft in the air.

  5. Once at the desired height, you can remove the jumper wire from the two terminals.

  6. Check the silver plunger that’s in the middle of the machine base (look under the scissor stack towards the rear of the machine). If it’s bent, the plunger will miss the limit switch in the bottom scissor and won’t allow your machine to elevate.

  7. With the scissor stack off the plunger, go to the lower control rocker switch and raise the machine to verify it's able to lift.

  8. To repair the bent plunger, remove the two Allen bolts that hold the plunger block down.

  9. Once removed, pull out the plunger, plunger spring, and plunger rod. The rod is what actually bends.


This is a very easy fix — only a few minutes are needed to get your machine back up and running. You have two options to fix a bent plunger rod:

  1. Pound the rod straight with a hammer and reinstall the rod upside down into the machine.

  2. Order a new plunger kit (112-21-426-50-K) that will come with a bigger Delrin block to avoid future bending to the plunger rod.


Click here for PDF of service document.


If you have any additional technical questions, don't hesitate to contact our service team at 262-297-5195. We're here to help you reach higher!




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