PRS-33 & PRS-33.2 Troubleshooting
With over 90 individual parts including an electric motor, the PRS-33 and PRS-33.2 are the most complex products made by Park Tool. As such, over time issues can present themselves. Fortunately, most common issues are easily addressed, often without the need for new parts.
Self-diagnosis can help you get a better understanding of the stand and how it works, and save you time and money spent contacting us. If you run into issues that don’t resolve with basic troubleshooting, do feel free to contact our customer support team.
Here are a few common issues we see, including methods for diagnosing the problem and how to fix it:
Incorrect Chain Tension
The carriage of the Power Lift Shop Stand moves up and down via a set of gears that engage a chain on the upright of the stand. When the tension of this chain is set too loose, it can start to exhibit the following symptoms:
- Ticking noise from undercarriage chain cover
- Carriage assembly drops slightly when downward button pushed
- Carriage assembly hesitates when changing directions
Tighten the chain using the turn buckle at the bottom of the stand in half-turn increments and reassess.
When the tension of the chain is set too tight, the motor can seem slow and/or begin to sound labored. Loosen the chain using the turn buckle at the bottom of the stand in half-turn increments and reassess. If loosening the chain didn’t address the issue, the quick release on the side of the carriage body may be too tight. Loosen the adjustment and reassess.
Loose Top Tube
If the top tube (the tube that holds the clamp assembly) wiggles or has rotational play, it is likely loose. Remove the carriage assembly and tighten the top tube — full instructions can be found in the video below:
If pressing the buttons on the PRS-33 does not raise or lower the stand, there are a number of ways to determine the problem. First, does the motor make noise when the buttons are pressed?
Motor Makes Noise
If the motor makes noise, but the clamp does not move up and down, remove the carriage cover and inspect to see whether the small drive gear turns when the buttons are pressed. If not, it is likely that the motor coupler screws have become disconnected. See the video below for the process of repairing this problem:
If the small drive gear does turn but it is not engaging the chain, inspect to see if it is stripped. If so, it will require replacement.
Motor Does Not Make Noise
If the motor does not make noise when buttons are pressed, further diagnosis will be required. Do not assume the motor is at fault, as this is rarely the case. Inspect each step in the power supply chain to verify that it is functional:
- Electrical outlet
- Power cord — ensure it is installed and fully seated in the power supply
- Power supply — green status light should be on
- Coil cord — should be tight on both ends
- Directional switch — ensure it is not in neutral
If this inspection did not reveal any problems, the wiring harness may be at fault. Verify this using a voltmeter (using appropriate precautions) if this is something you are comfortable doing. The video below outlines the process of replacing the wiring harness: