How to Replace a Bosch Dishwasher Drainage Hose

Flip the circuit breaker switch that connects to the dishwasher on the household electrical panel to the “off” position. Cover the switch with a strip of masking tape to prevent someone else from restoring power while you’re working.

Remove the two screws securing the dishwasher retaining brackets to the underside of the kitchen counter with a Phillips screwdriver. Slide the dishwasher out of its cavity far enough for you to reach through to the back wall.

Pull the kick plate out of the retaining clips holding it to the lower front of the machine.

Locate the drain hose under the front of the dishwasher leading to the sink plumbing; the white ribbed plastic hose is connected to a black rubber transition tube on the short dishwasher drain hose attached to the pump.

Compress the lugs on the side of the spring-type hose clamp with a pair of channel pliers and pull the defective hose out of the transition tube; leave the hose clamp around the transition tube and pull the old hose out from under the dishwasher.

Reach under the sink and undo the compression fitting connecting the defective hose to the drain inlet above the P-trap with an adjustable wrench. Pull the old hose through the hole in the side of the sink cabinet and discard it.

Thread a new dishwasher drain hose through the hole in the side of the sink cabinet and screw the attached compression fitting onto the drain inlet above the P-trap. Snug the fitting down with the adjustable wrench, but do not over tighten; this will damage the rubber seal inside the fitting.

Pull the new drain hose protruding through the side of the sink cabinet out, and slide the end under the dishwasher so that it sticks out from under the front of the machine.

Slide the dishwasher back into the cavity and line both sides up with the edges of the adjacent cabinets; if necessary screw the threaded leveling feet attached to the bottom of the dishwasher up or down with the channel pliers until both sides of the machine are plumb.

Secure the dishwasher retaining brackets back onto the underside of the countertop with the screws removed earlier.

Compress the lugs on the hose clamp around the rubber transition piece with the channel pliers. Insert the end of the replacement hose all the way into the transition piece so that the ribbed bead in the end of the hose slides past the hose clamp. Release the hose clamp lugs.

Restore power to the dishwasher and run a full wash cycle. Check to ensure the ends of the new hose are not leaking; tighten the compression coupling on the sink drain another quarter turn if necessary. Replace the dishwasher kick plate to complete the installation.