Safety And Scope
Disconnect power before touching any internal parts. Let the cabinet cool fully. Work only on the motor, blower wheel, belt path, and mounting hardware. Panel work, circuit changes, or hidden duct rerouting sit outside DIY scope. If you see heat-discoloured wiring, a melted terminal block, or smell gas on a gas model, stop and book a licensed professional. Keep photos of every harness route and fastener so reassembly follows the original layout. Place small parts in labelled containers to avoid cabinet rattles later.
Symptoms And First Checks
Motor faults present as a low hum with no drum movement, a sharp click as a protector opens, or a harsh grind from seized bearings. Rule out simple causes first. Remove the lint screen and clear the cavity. Inspect the belt for glazing or broken cords. Rotate the empty drum by hand from the door opening. Smooth, light rotation indicates the drum is free; heavy spots or scraping point to seized support rollers or a torn felt seal that can stall a good motor. Check the blower inlet for screws, coins, or hardened lint that can lock the wheel. Confirm strong airflow at the exterior cap; a blocked vent overheats the cabinet and can trip safeties, mimicking a motor failure.
Confirming A Failed Motor
Unplug the dryer and pull it forward for light. Remove the front or rear service panel as your service manual specifies. Slip the belt off the idler and motor pulley, then spin the motor shaft. A healthy shaft turns freely and coasts to a stop without lateral rock. Gritty rotation or end play that you can feel with a fingertip signals worn bearings. If the blower wheel is still attached, hold it while checking shaft play to isolate the motor itself.
Test electrically with a digital multimeter. Isolate the motor by removing the harness connector so your readings are not back-feeding through the loom. Identify run and start terminals from the wiring diagram. Typical cold resistance: run winding in the low single-digits of ohms, often around two to five; start winding slightly higher, commonly three to ten. Values drift by design and model, so compare to documentation for your unit. Infinite resistance indicates an open winding. Near-zero readings or continuity from either winding to the frame indicate a short and require replacement. If your model uses a start capacitor, read its value on the case and measure with a capacitance function; a common range is four to ten microfarads. Anything off by more than ten to fifteen percent suggests replacement. If the motor only hums with the belt removed, and windings and capacitor test in range, the centrifugal switch may be faulty; this switch is integral on most dryer motors and is replaced with the motor assembly.
As a final check, measure current draw with a clamp meter during a brief powered test after reassembly without clothes. Compare to the motor nameplate or service data. An unloaded motor that draws well above spec is binding or miswired. Do not prolong powered tests if the motor does not come to speed within a second or two.
Replacement Procedure
Work methodically and keep the cabinet stable. Lay a protective pad under the front to avoid finish damage. Photograph the belt path and harness clips before you loosen anything. The goal is clean removal, accurate transfer of parts, and precise alignment on reinstall.
Access And Isolate
Remove the front panel or lower access as required, then lift the top for room. Release belt tension at the idler and lift the belt free of the motor pulley. Detach the blower housing cover if the wheel is internal. Unplug the motor harness and note each wire position from your photo. If your model includes a thermal protector on the motor body, trace its leads so they return to the same terminals later.
Remove The Old Motor
Hold the blower wheel and loosen the motor pulley nut or the blower hub in the direction indicated in your manual; many threads are reverse on one side to prevent self-loosening in service. Slide the belt off, then release the motor clamps or bolts. Lift the motor straight up to keep rubber mounts square. Inspect the mounts and base for heat marks or cracks. Replace any deformed isolation grommets; excessive compression transmits vibration and adds noise.
Transfer Parts
Move the pulley and, if external, the blower wheel to the new motor. Clean mating bores and shafts with a dry cloth. Do not lubricate the shaft; oils migrate and catch lint. Align flats or keyways exactly and tighten to the specified torque. Transfer any motor shrouds, brackets, or wire guides so airflow and cooling match the original layout.
Install And Align
Seat the motor in its cradle and secure clamps or bolts evenly so the body sits level. Refit the belt over the motor pulley, then route it over the idler with the grooved side on the drum where applicable. Align the pulley faces by eye from above; a misaligned belt chirps and sheds rubber. Spin the drum by hand. It should complete several smooth revolutions without rubbing. Reconnect the harness and anchor every clip; loose wiring buzzes against panels at speed.
Reassembly And Set-Up
Vacuum lint from the blower inlet and heater tunnel while the cabinet is open. Reinstall covers and panels in the reverse order of removal. Confirm the door switch connector is seated; a missed switch creates a false “dead” condition. Push the dryer back into place without crushing the duct. Reconnect power and prepare for proving tests.
Proving The Fix And When To Call A Pro
Run a timed cycle with no load. The motor should come to speed immediately with a steady hum and no scraping or rattle. Step outside and feel for strong, uniform airflow at the outlet cap. Add a single damp towel and listen through one full minute. New thumps point to flat-spotted support rollers; high-pitched chirps suggest belt misalignment; cabinet buzz often traces to a loose harness clip or panel screw. Correct these before regular use.
Use practical thresholds to judge results. Shaft end play should feel minimal by hand and not translate to visible pulley wobble. Motor temperature at the shell should rise but remain touch-safe during a light-load test. Current draw should sit near the service figure for your model, typically in the mid-single-amp range for the motor circuit on many designs; readings materially above spec indicate binding or miswire. Airflow should open the exterior flap briskly and hold it open during the cycle; a weak stream stresses the blower and can overheat the cabinet.
Stop DIY immediately if the motor fails to reach speed, if breakers trip, if you catch a burned odour, or if any wiring or connectors heat rapidly. Do not attempt supply troubleshooting at the service panel or modify receptacles. Those tasks require licensed trades and compliance with electrical and building codes. If your meter shows healthy windings but the motor still stalls under load, the control board, relay, or timer path may be at fault and should be evaluated by a qualified technician.
FAQ
How do I tell a bad motor from a seized roller?
Remove belt tension and try the drum. If the drum then spins freely by hand but the motor shaft feels rough or will not start under power, the motor is suspect. If the drum remains heavy and lumpy, address rollers or seals first.
What resistance should I see on the windings?
Expect a low-ohm run winding and a higher start winding, often two to five ohms and three to ten ohms respectively at room temperature. Compare your readings with the service data for the exact model.
Does a humming sound always mean a dead motor?
No. A blocked blower, a jammed wheel, or a belt wrapped around the pulley can stall a good motor. Clear obstructions and retest before condemning the part.
Should I replace the start capacitor at the same time?
If your model uses one and its measured capacitance drifts more than ten to fifteen percent from the value on its case, replace it with the motor. Weak capacitance prevents reliable start-up and overheats windings.
Is lubrication a valid fix for squeals at the motor?
No. Dryer motors are built with sealed bearings or self-lubricating bushings. Adding oil attracts lint, raises temperatures, and shortens life. Replace worn components instead.
Sources
- Manufacturer Service Manual — Model-Specific. Wiring diagrams, resistance values, torque specifications, and belt routing for your exact dryer.
- International Electrotechnical Commission — IEC 60335 Series, Household And Similar Electrical Appliances — Safety. Safety framework for servicing user-accessible components.
- UL 2158 — Electric Clothes Dryers. Performance and safety requirements relevant to motor protection, airflow, and thermal limits.
- National Fire Protection Association — NFPA 70, National Electrical Code. Installation and safety requirements governing branch circuits and receptacles that supply dryers.
