Symptoms
- Water only leaks when the dishwasher runs
- Drip comes from the side nipple on the disposal
- Puddle appears during the dishwasher's drain cycle
- No leak when disposal runs alone
Likely causes
- CommonLoose hose clamp on the dishwasher drain hoseClamps can loosen over time from vibration.
- CommonKnockout plug not removed before connecting a new dishwasherNew disposals ship with a plug in the dishwasher inlet that must be knocked out first, or the connection will back up and leak.
- PossibleCracked or split dishwasher drain hoseRubber hoses degrade and crack with age and heat.
- Less commonDamaged inlet nipple on the disposalCross-threading or over-tightening can crack the plastic nipple.
What to do
- Turn off the dishwasher and disposal power before inspecting.
- Locate the side nipple on the disposal where the dishwasher hose connects.
- Check the hose clamp for looseness and tighten it with a screwdriver if needed.
- Inspect the hose itself for cracks or a stiff, brittle feel and replace if damaged.
- If this is a new installation, confirm the plastic knockout plug inside the nipple was removed before the hose was attached.
- Run the dishwasher's drain cycle and watch the connection closely for drips.
- Reseat and re-clamp the hose if any movement or seepage is visible.
Tools and parts
- Screwdriver
- Flashlight
- Towel
Dishwasher drain hoseSearch: “dishwasher drain hose replacement”
Hose clampSearch: “stainless steel hose clamp small”
When to call a pro
If the leak persists after tightening and replacing the hose, a plumber can check whether the knockout plug was left in place.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.