Symptoms
- Knob spins freely without engaging the switch
- Knob is cracked or a piece has broken off
- Knob is missing entirely, leaving an exposed shaft
- Knob feels loose or wobbly on the shaft
Likely causes
- CommonCracked or worn plastic knobRepeated turning and heat exposure over years can crack or wear down the knob material.
- CommonStripped internal knob mechanism no longer gripping the shaftThe plastic insert inside the knob that grips the metal shaft can wear smooth and stop engaging properly.
- PossibleBent or damaged control shaftThe metal shaft itself can bend from a knob being forced or bumped.
- PossibleWorn switch behind the knob, not the knob itselfIf a new knob still doesn't engage properly, the switch mechanism behind it may be the actual problem.
What to do
- Remove the loose or broken knob by pulling it straight off the shaft.
- Inspect the shaft for any bending or damage.
- Check the knob's inner mechanism for wear, cracking, or a stripped grip area.
- Order a replacement knob matching your exact model, since fit varies between brands.
- Press the new knob firmly onto the shaft, checking that it engages and turns the switch properly through its full range.
- If a new knob still spins freely or doesn't fully engage the switch, the issue is likely the switch behind it, not the knob.
- Have a technician replace the underlying switch if a new knob doesn't resolve the issue.
Tools and parts
Oven/cooktop control knobSearch: “oven range knob replacement”
When to call a pro
If a new knob doesn't properly engage the switch, have a technician replace the underlying infinite or selector switch.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.