Had to choose between a new $1200 hoist motor or rebuilding the old one on a 1980s Otis unit last Tuesday. Went with the rebuild.

The old motor was making that classic grinding noise, you know the one. Boss wanted to just slap a new one in and bill for it, but I had a feeling the armature was still good. Took it apart in the shop and sure enough, it was just the brushes and commutator were shot. Three hours of cleaning and new parts later, it purrs like a kitten. Saved the building manager a chunk of change and I got to keep a piece of history running. Anyone ever had a rebuild surprise them by holding up for years after?

3 comments

3 Comments

zarat3728d ago

Wait, you got it done in just three hours? That seems crazy fast for a full teardown and rebuild... I've seen guys spend a whole day just getting one of those old motors out of the machine. Did you have all the parts just sitting on a shelf or something? I guess if the armature was truly clean it would go quicker, but still. Makes me wonder if my shop is just moving slow.

white.keith28d ago

Right? It's all about having the right tools laid out and not fighting old bolts. Last time I had a clean bench and my impact driver ready, I pulled a motor in like 45 minutes. But if you're searching for a socket or rounding off a rusty nut, yeah, it'll eat a whole day. Some shops just get bogged down in the small stuff.

kimblack28d ago

Keith's 45 minutes was just for the motor pull, not the whole rebuild. That's still really good for a pull on an older machine. A full teardown, clean, and reassembly is always a multi-hour job, even with parts ready. He's right that a clean workspace and the right tools just get you to the actual work faster.