Electric motor shaft and endbell repair
We repair the mechanical fits of electric motors: worn bearing journals on the shaft, damaged keyways and shaft ends, and endbell bearing bores that have gone oversize. The metal is built up and machined back to size.
- Built from your specifications, drawings or samples
- Free consultations, prompt estimates
- Wolf Machine stands behind the work we perform
- Reno shop, Monday to Friday, 7:00 am to 3:30 pm
Stock photo: a lathe turning a bar, hot chips flying
When a motor bearing spins on its journal or in its endbell, the motor can be electrically fine and still be junk. Electric motor shaft and endbell repair is one of the things we specialize in, and the repair is metal work: build up, machine, fit.
At a glance
- Bearing journals on motor shafts rebuilt
- Endbell bearing bores brought back to size
- Keyways and shaft ends repaired
- Metal spray and machining for exact fits
Love working with these guys, and gal. Great customer service and knowledgeable skill base. They have helped with many big projects and have always pulled though when our machines went down.
How a motor ends up with a bad fit
Motor bearings are pressed on the shaft and into the endbell with a tight fit. When a bearing runs hot or loses its preload, the inner race creeps on the shaft or the outer race turns in the endbell. The surface wears smooth and undersize, and the new bearing you install next will not grip it either.
Repeated bearing failures on the same motor are the usual sign that the shaft journal or the endbell bore is the real problem.
The repair, in order
For a journal, the worn area is built up with metal spray, then turned to the bearing size. For an endbell, the oversize bore is built up and bored back to a round, true size. A damaged keyway is cut again, in the same place or in a fresh location, as covered on our shafts, threads and keyways page.
All of this is the mechanical side of the motor. The motor comes to us stripped down to the shaft and the endbells.
Why repeated bearing failures point here
A motor that eats a bearing every few months is usually telling you the seat is gone, not that the bearings are poor. A rebuilt journal and a round endbell bore give the next bearing the tight fit it needs to last. If the same motor keeps coming back with the same failure, send the shaft and endbells and we will look at the fits.
What to send
Bring or send the shaft and the endbells. Photos of the worn journal and bore are useful, along with the motor frame size or nameplate and what the motor drives. Call (775) 359-5570, or use the quote request and attach the pictures.
- Remove the bearings and note which one failed.
- Photograph the journal, the bore and the keyway.
- Send the photos with the quote request or call the shop.
- We review and respond with questions or a prompt estimate.
Sources
- Wolf Machine & Fabrication services list (2026-10-18)
- Key (engineering) (Wikipedia) (2026-10-18)
Mechanical damage we see on motors
- A bearing journal worn smaller than the bearing bore
- An endbell bore that has gone oversize from a spun outer race
- A keyway beaten out by a loose coupling or pulley
- A damaged shaft end, thread or shoulder
- Scoring where a seal rides
Typical parts
- Motor shafts
- Endbells (end shields)
- Shaft ends and threads
- Coupling and pulley seats
How to send us the job
Send a drawing (PDF, DWG, DXF, STEP or IGES), a sketch with sizes, or photos of the part with a tape or scale in the shot. A sample works too: bring it to the shop.
Questions about this service
From the shop
Work from the shop
Bring it back to size
How a worn diameter is rebuilt
01WornThe bearing or seal diameter has worn under size.
02Built upMetal spray or a sleeve adds new material over the worn area.
03Machined to sizeThen it is machined back to the original diameter.
Bearing and seal areas: metal spray or sleeve repair, on shafts, housings and pistons.
Straight answers
Electric motor shaft and endbell repair questions
Still have a question? Call (775) 359-5570, Monday to Friday, 7:00 am to 3:30 pm.
Can a worn motor shaft be saved?
Often, yes. A worn journal is built up and machined back to the bearing size. A shaft that is bent or cracked through is replaced with a new one machined to the same sizes.
Can you recut a keyway?
Yes. We key shafts. Send the shaft or the coupling details and the key size.
Send us the job
Request a quote
Tell us what you need, attach a drawing or photos of the part, and we will get back to you during shop hours. Free consultations; prompt estimates.
- From your specifications, drawings or samples. We can also assist you in designing your product or part.
- Free consultations and prompt estimates
- Stands behind the work: Our rates are very competitive and our quality is second-to-none. Wolf Machine stands behind the work we perform.
- Company accounts: all major credit cards, or we can open an account for your company
Shop hours Monday to Friday, 7:00 am to 3:30 pm. Send your request any time and we will get back to you during shop hours.
Stock photo: a lathe turning a bar, hot chips flying