How to replace the sump gasket on a Bosch dishwasher

Is your Bosch dishwasher leaking and causing a kitchen catastrophe? The culprit might be a worn-out sump gasket, but don’t worry—fixing it is a breeze! With our step-by-step guide and handy how-to video below, you’ll have your dishwasher running leak-free in no time.

Looking for the right part? Enter your appliance model number below to find the exact match and get your appliance running like new again!

On a Bosch dishwasher, the sump gasket seals the large opening at the bottom of the dishwasher cabinet where the sump is mounted. Over time, this gasket can wear out or become damaged, leading to leaks.

Replacing the sump gasket is a relatively quick and straightforward repair that can save you the hassle and expense of calling a professional. Let’s get started!

Watch here: How To: Bosch/Thermador/Gaggenau Sump Gasket 00263102

The information in this article may not apply to your specific appliance model. We recommend consulting your manufacturer’s documentation or contact us with any questions.

Tools needed 

• Phillips screwdriver
• Torx 20 screwdriver
• 5/8″ wrench
• 5/16″ nut driver
• Needle nose pliers
• Liquid soap
• Towel
• Container

Safety precautions

• Always power off and unplug your appliance or switch off the circuit breaker before attempting any maintenance or replacement work. This keeps you safe by preventing any risk of injury from electric shock.
• Turn off the water supply at the outlet before beginning repairs to any appliance parts that hold water. Have towels ready for any residual water in the system when removing parts. 
• Wear insulated work gloves to protect your hands from sharp metal parts, pinching hazards and debris.
• Don’t test wiring with a multimeter for live voltage if you’re unfamiliar with how to prevent short circuiting when testing. 
• When working with wires, avoid touching any exposed wires or terminals. If you need to touch a wire, use a non-conductive tool or wear insulating gloves to prevent electrical shock.
• Take your time and don’t rush while working to prevent accidents and personal injuries.
• Work in a well-lit area so you can clearly see and access the interior parts.
• Clear your workspace of clutter and other obstacles. Keep children and pets away from the work area.
• Never work on internal parts with bare wet hands. Make sure the work area is completely dry.
• Check your user manual to see if there are specific installation or safety instructions for your part or appliance. 
• Be gentle when handling or removing parts. Excessive force might damage the appliance or cause injury.
• Wear safety glasses when working with chemicals, dust or cleaning large debris to prevent injury. 
• If the appliance has recently been used, give it plenty of time for any heating parts to cool down before working on it. 

Replacement steps

Disassembly

1. Open the door and use a philips screwdriver to remove the two screws on the mounting brackets that hold the dishwasher to the countertop or cabinet.
2. Pull out the lower dish rack.
3. Remove the lower spray arm by pulling it straight up.
4. Unscrew and remove the filter basket by turning it counterclockwise.
5. Remove the fine filter.
6. Take out the two torx 20 screws that hold the spray arm support to the sump housing.
7. Remove two torx screws and remove both sump supports using a Torx 20 screwdriver.
8. Take out the six screws that hold the outer door, three on each side.
9. Close the door and pull the outer panel down and out to remove it.
10. Use a philips screwdriver to remove the two screws on the sides of the kick panel.
11. Remove the kick panel.
12. Take out the screws and remove the inner access panel.
13. Remove the plastic cover from the inner access panel.
14. Remove the insulation.
15. Place a towel and a plastic container under the shut-off valve.
16. Use a 5/8 open-ended wrench to remove the water line.
17. Use a 5/16 inch nut driver to loosen up the hose clamp and remove the drain hose from the air gap or garbage disposal.
18. Pull the dishwasher out.
19. Take out four screws that hold the side panels, two on each side.
20. Remove one side panel.
21. Close the door.
22. Remove the hinge rope cover using needle-nose pliers.
23. Remove the hinge rope hook from the door hinge.
24. Repeat the procedure on the opposite side.
25. Take out the screws in the front and two in the back that hold the base to the cabinet.
26. Lay the dishwasher on its back.
27. Remove the pressure chamber to sump hose from the retainer.
28. Pull the hose out of the top of the sump. Rotate the hose out of the way.
29. Use the torx screwdriver to remove two corner bracket screws.
30. Pull the base off the dishwasher cabinet.
31. Hold the sump and motor assembly so it won’t fall down.
32. Remove the old sump gasket.
33. Clean the opening.

Installation

1. Put some liquid soap on the new sump gasket.
2. Install the new sump gasket by pushing it into place.
3. Push the base in so the sump gasket is mounted over the opening.
4. Place the two motor supports into the openings in the base, making sure that the sump bottom support is properly seated on the rubber pad.
5. Match the holes and install the two torx 20 screws at the brackets.
6. Insert the pressure chamber to sump hose and push it in as far as it will go. Tuck it under the retainer. Lock the terminal cover down.
7. Slowly lift the dishwasher upright.
8. Secure the base to the dishwasher cabinet with two torx 20 screws in front and two at the back.
9. Use needle-nose pliers to reinstall the hinge rope hook on the hinge.
10. Install the hinge rope cover and repeat the procedures on the other side.
11. Install the side panels first at the bottom, then the two plastic tabs at the rear.
12. Install the dishwasher under the counter.
13. Pull the drain hose, the inlet hose, and the power cord through the divider.
14. Thread on the waterline onto the shut-off valve and tighten it.
15. Connect the drain hose to the air gap and tighten the clamp.
16. Place the insulation in place. Clip on the plastic cover.
17. Install the inner access panel and secure it with two torx 20 screws.
18. Install the kick panel and secure it with the two philips screws.
19. Install the outer door panel and secure it to the inner door.
20. Open the door. Install the two sump supports and secure them with two torx 20 screws.
21. Install both spray arm support screws.
22. Install the fine filter. Screw in the filter basket by turning it clockwise.
23. Reinstall the lower spray arm by pushing it in until it locks.
24. Slide in the lower dish rack.
25. Use the philips screwdriver to secure the dishwasher to the countertop with the two screws.
26. Close the door. Turn the water on. Plug in the power cord. Run the dishwasher to check for leaks.

Additional information

Thanks for reading! We hope this guide helped you replace the sump gasket on your Bosch dishwasher. 

If you still need some replacement parts, grab your model number and head over to AppliancePartsPros.com. We offer over two million parts and most orders arrive in two business days. If you need some help with finding the right part or placing an order, you can contact our team at 1 (877) 477-7278.

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