If you’ve ever walked into a plant on a Monday morning and heard a motor bearing shrieking like a demon trapped in a shop-vac, congratulations. You’ve just experienced the downstream effects of pretending motors fail “out of nowhere.”
They don’t.
Motors degrade slowly, predictably, and with plenty of warning. We just miss it. Or worse, we design PMs that politely refuse to notice. That’s why most motor failures feel sudden when they shouldn’t. If this sounds familiar, it helps to step back and understand why motors don’t fail suddenly in the first place.
A fool-proof motor PM program doesn’t require a reliability PhD or a vibration lab. It requires discipline. Repeatability. And PMs that are built around how motors actually fall apart.
Here’s how to build one that survives real plant conditions.
Why Your Motor PM Program Needs to Exist
(a.k.a. what happens when it doesn’t)
Industrial motors fail along the same fault lines everywhere: heat, contamination, vibration, lubrication mistakes, misalignment, electrical stress, and the classic “somebody tightened the belt until the motor cried uncle.”
These aren’t mysteries. They’re patterns.
A good PM program catches problems before they escalate. Not because it does more checks, but because it knows where motors show early distress and focuses attention there.
That includes things like bearings starting to wear, airflow slowly degrading, vibration drifting out of character, and electrical conditions that haven’t announced themselves yet.
Step 1: Build a Motor Inventory
(Yes, all of them)
You can’t maintain what you can’t name.
Before you write a single PM, build a complete motor inventory:
-
Horsepower
-
RPM
-
Voltage
-
Frame size
-
Drive method
-
Environment
-
Duty cycle
This inventory becomes the backbone of your PM program. Without it, you’re just reacting to whatever screams loudest.
Step 2: Standardize PM Tasks
(Stop making techs guess)
A PM that says “inspect motor” is not maintenance. It’s a vibe.
Standardize your checks so every motor PM looks the same, regardless of who created it or who runs it. Mechanical, electrical, environmental, operational. Same order. Same expectations. Same language.
This is how you avoid PMs that feel complete but accomplish nothing.
It also prevents the most common failure mode of all: PMs that look thorough but ignore bearing failures leave clues right in front of them.
Step 3: Set Frequencies Based on Risk
(Not tradition)
Monthly. Quarterly. Annual. None of these mean anything without context.
Frequency should be driven by duty cycle, environment, failure history, and consequence of downtime. Not “because that’s how we’ve always done it.”
Most plants need fewer PMs executed better, not more PMs executed poorly.
Step 4: Use Templates Techs Will Actually Follow
If your PM template looks like it was stitched together from three supervisors and a 1998 CMMS export, your techs won’t follow it. They’ll survive it.
Good PM templates are clean, predictable, and written in plain language. They guide attention instead of overwhelming it.
Step 5: Record Data Like It Matters
(Because it does)
Checkboxes don’t predict failures. Trends do.
Record amps, temperature, vibration, belt tension, alignment. Then look at how those numbers change over time.
Just don’t assume numbers always tell the truth. Especially vibration. Sometimes when vibration lies, it lies very convincingly.
Step 6: Close the Loop or Don’t Bother
A PM program only works if findings turn into corrective action.
PM completed.
Issue noted.
Follow-up work issued.
Problem corrected.
No loop means no program. Just paperwork.
Want a Faster Way to Get There?
Once you understand how motors fail and how PMs should be structured, the hardest part is writing clean, consistent tasks that techs can actually use.
If you want a shortcut, our library of failure-based PM task lists can give you a solid starting point without reinventing the wheel or copying bad examples from the internet.
Good PMs don’t prevent every failure.
They prevent surprises.