I'm the office administrator for a property management company, and I handle purchasing for the maintenance team—roughly 60-80 repair orders a year. I took over this job in 2020, so I know how to process an invoice, but I don't know how to rebuild a motor. That gap in knowledge cost us a lot of money.
When the third motor failed on one boat lift, I was ready to write off the entire Leeson-motor lineup. I'm glad I didn't. The motors weren't the real problem. We were.
The surface problem: another Leeson motor 5 hp quit
In summer 2023, the 5 HP motor on a boat lift at one of our communities seized up. The lift is used to raise and lower a small service boat, and when it stopped, people noticed. We ordered a Leeson motor 5 hp model from our regular distributor—same spec, same frame, same duty rating. A month later, it sounded rough. Two months later, it was dead. We replaced it again. It failed six weeks after that.
At that point, I had two options: find a different vendor or figure out why a brand-new motor kept dying. The cheaper option, in the short term, was to blame the brand and switch. I'm glad we didn't do that.
The deeper problem: the motor wasn't the culprit
The maintenance tech pulled the second failed motor and found serious wear on the front bearing. The shaft had scored the bearing surface. That isn't normal after six weeks. Something else was attacking the motor.
The supplier asked if we wanted to send the failed motor in for a failure analysis. I said no because it cost extra and I was already over budget. That was a mistake. The diagnostic step is where the answers were, and we skipped it twice.
The motor shaft coupling was doing the damage
A motor doesn't sit by itself. It connects to a gearbox or driven shaft through a coupling. In our case, the motor shaft coupling was a rigid coupling with about 3/16 inch of offset. That number sounds small, but at 1,750 rpm it creates a constant side load. The front bearing was trying to hold the shaft straight while the coupling was yanking it sideways. No bearing can survive that for long.
People think a motor fails because of age or poor manufacturing. Sometimes it does. But in this case, the causation ran the other way: the motor failed because the installation was wrong. A new motor with the same misaligned coupling was going to fail exactly the same way.
I didn't follow the Leeson boat lift motor wiring diagram
There's a second part of the story that's a little embarrassing. When the second motor was installed, nobody verified the voltage. I assumed the tech had it handled. I was wrong. After the failure, I found the Leeson boat lift motor wiring diagram in the box and walked through the connections with a more experienced electrician. The motor had been wired for the wrong supply voltage for that installation. It ran, but it ran hot. According to NEMA MG 1, running a motor outside its rated voltage range increases temperature and reduces insulation life. That's exactly what happened.
The wiring diagram is not paperwork. It's a diagnostic map. I now treat it like a pre-flight checklist.
What's a ball bearing? More importantly, why did it fail?
If you're like me and had to ask 'what's a ball bearing?', this part is for you. A ball bearing is a set of steel balls that lets the motor shaft rotate while keeping it centered. It's a precision part, not a generic metal ring. It carries the load and, if it dies, the motor seizes or grinds.
The failed motors had open bearings. The seal where the shaft exits the motor had worn, so moisture got in. Water washed the grease out and contamination scored the balls. When we replaced the motor again, we ordered one with sealed bearings. That fixed one failure path, but only after we fixed the coupling and wiring.
Belt drives and the timing belt diagram lesson
We had a different motor that kept throwing belts, and the tech kept tightening it until it 'felt right.' That's not a spec. Too much belt tension pulls the shaft downward and loads the bearing. If you've ever looked at a timing belt diagram, you've seen that it specifies tooth profile, length, and tension. A V-belt drive is no different. We now use a tension gauge for any belt-driven motor instead of guesswork.
What these failures actually cost
Three motor replacements in one season cost us about $2,400 in parts and labor, based on our 2024 invoices. That's annoying but survivable. The bigger cost was reputation. A boat lift that doesn't work is visible. Residents complained. Board members asked questions. If you run a property, that kind of thing becomes part of your brand, whether you like it or not.
In my opinion, that visible downtime does more damage to a property brand than a $300 repair invoice. There was a moment when I could have ordered a reconditioned motor for $300 less. The upside was saving the budget. The risk was another failure and another season of complaints. I asked myself whether $300 was worth the chance of looking bad to the board. It wasn't. The numbers said the reconditioned motor had the same spec. My gut said no. I went with my gut, and I don't regret it.
A short checklist for any motor replacement
I'm not an engineer, so take this as a buyer's checklist, not a technical guide. Before you order another motor, do this:
- Check the motor shaft coupling alignment. If it's worn or offset, fix it first.
- Verify the supply voltage against the wiring diagram. If there's a mismatch, you're cooking the motor.
- Ask about sealed bearings if the motor is in a damp or dusty environment.
- Use the specified belt tension and pulley alignment for belt-driven loads.
- Run a test cycle before putting the equipment back in service.
As of January 2025, that boat lift motor has been running for about ten months without a repeat failure. That's not proof we've solved everything, but it's a good sign. My experience is based on maybe 40 motor purchases and repairs across six properties. If you're running a factory with hundreds of motors, your experience might be different. But from where I sit, I think the same lesson keeps showing up: the motor is usually the victim, not the cause.
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