Drum won't tumble on your Whirlpool LGR7646EZ1
A dryer where the drum won't tumble breaks down into two very different failure patterns, and the sound of the machine at startup tells you which one you have. If you press start and hear the motor hum or a brief whir before silence, the motor is getting power but something is physically stopping the drum from turning — usually a broken drive belt, a seized roller, or a failed idler pulley. If you press start and nothing happens at all — no sound, no lights, no click — the motor never received the command to run, which points at the control circuit: door switch, thermal fuse, start switch, or motor relay. These are genuinely different repairs with different parts. Confirming which category your symptom falls into before ordering parts avoids the common mistake of replacing a belt on a dryer whose real problem is a blown thermal fuse buried behind the blower housing.
Safety
Critical- Disconnect power before cabinet disassembly: Electric dryers run on 240V and gas dryers still carry 120V to the motor and controls. Always unplug the dryer or turn off both circuit breakers before removing panels to access the belt, motor, or thermal fuse.
- Tensioned idler springs can snap back: The idler pulley is held under load by a strong spring that keeps the drive belt taut. When releasing belt tension during removal, control the pulley with your hand — a released spring can snap back hard enough to cut skin, crack plastic housings, or dislodge adjacent components.
- Sharp drum and cabinet edges: Removing the drum exposes sheet metal edges that can be surprisingly sharp, especially on older machines with corroded seams. Wear cut-resistant gloves when lifting the drum out of the cabinet and when handling it during roller or felt seal replacement.
- A blown thermal fuse signals a prior overheat: A thermal fuse blows because the dryer previously reached an unsafe temperature — almost always from a restricted exhaust vent. Replacing the fuse without finding and fixing the underlying airflow problem will blow the new fuse quickly and allow repeated overheating.
How to approach this
Start by pressing the start button with an ear on the cabinet and paying attention to the first second of response. A motor hum with no drum rotation means power is reaching the motor but mechanical rotation is blocked — open the cabinet and check belt condition first, then rotate the drum by hand to feel for seized rollers or a bound bearing. A free-spinning drum with a motor that runs briefly before shutting off usually means the belt has snapped — the motor has no load, hits a safety threshold, and cuts out. If you hear nothing at all when pressing start, the control circuit is broken. Push the door firmly closed and listen for the door switch click; a sticky switch plunger that doesn't fully depress leaves the dryer convinced the door is open. Next, test the thermal fuse for continuity — on most dryer brands, the thermal fuse sits in the motor's control circuit, so when it blows, the entire machine goes dead, not just the heating element. This is the single most commonly misdiagnosed no-start condition.
Common causes
Ordered by how frequently each component is involved, based on service manual analysis.
Broken drive belt
Most commonThe drive belt wraps around the drum, the motor pulley, and a spring-loaded idler pulley. It thins and cracks over years of heat cycling until it snaps — usually silently, because the rubberized belt cuts cleanly rather than shredding. The symptom is a motor that runs for a second or two, hits a safety threshold because there's no load, and shuts off. The drum spins completely freely by hand when you open the door.
Blown thermal fuse
Most commonOn most dryer brands, the thermal fuse is wired in series with the drive motor — not just the heating circuit. When it blows (almost always from a restricted exhaust vent causing overheating), the entire dryer goes dead: no drum motion, no heat, no timer advance. This is the single most commonly misdiagnosed no-start condition because the failure mode looks like a control-board problem but is actually a consequence of airflow restriction.
Seized drum rollers or idler pulley
CommonDrum rollers support the drum on fixed axles. They wear, flat-spot, or seize. A seized roller creates enough drag that the motor hums but can't rotate the drum. The idler pulley, which maintains belt tension, uses a small internal bearing that fails similarly — except when the idler seizes, the belt often slips off or burns through from friction against a stationary pulley.
Faulty door switch
CommonThe door switch is a safety interlock that tells the dryer the door is closed. A sticky plunger, bent actuator, or worn contacts leaves the dryer convinced the door is open even when it isn't. The symptom is a completely dead dryer when you press start, often with no click from the motor relay. Door switches are typically under $20 and are accessible behind the top or front panel.
Worn start switch or motor relay
CommonThe start button is a momentary switch that only makes contact for roughly a second — just long enough for the motor relay to latch and take over. Carbon wear or contamination in the start switch can stop it from making clean contact during that brief window. A faulty motor relay on the control board shows similar symptoms. Continuity-test the switch first; if it reads good, the relay is the next suspect.
Drive motor failure
Less commonThe drive motor fails in one of two patterns: a hum-and-no-spin condition where the start winding has failed and the motor can't get rotation going, or an intermittent stop-and-start where the thermal overload protector inside the motor trips. A hum lasting more than a few seconds without any drum or pulley movement — combined with a drum that spins freely by hand — is a strong motor-failure indicator.
Verified Components
Parts
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About this content. Common causes and FAQs are generated from OEM service manual analysis and verified parts data. This is general guidance — your specific model may have different components or access points. Always verify with your model's documentation before ordering parts.