How to Install Dishwasher Sump AJH32598001 in an LG Dishwasher

Quick answer: Cut power and water and pull the LG dishwasher out. Remove the spray arm and filter, release the sump fasteners from inside the tub, tip the unit and disconnect the motor, drain pump and hoses below. Seat AJH32598001 with its new gasket, refit everything and run a cycle watching for leaks.

The sump on an LG dishwasher is the molded basin under the center of the tub floor. It collects the wash water below the filter, feeds it to the wash motor, and gives the drain pump its pickup. Part AJH32598001 is the replacement sump for models such as the LSDF995ST, LSD795ST4, LDF6920WW and LSDF795ST. A sump needs replacing when the plastic cracks at a hose port or around the motor mount, when the tub seal groove is damaged, or when a broken internal check valve lets dirty water flow back into the tub after draining.

This is one of the bigger dishwasher repairs. The sump is sealed to the tub from inside and everything else hangs off it from below, so the dishwasher must come out of the cabinet and be tipped or laid back on a padded surface to reach the underside. Set aside a full afternoon, take photos at every stage, and keep a tray for the many screws and clamps.

See part details and every compatible model: AJH32598001

⚠️ Safety First
  • Turn off the breaker and verify the control panel is dead before opening the junction box.
  • Close the water valve and relieve pressure before loosening the inlet fitting.
  • Wear gloves. The stainless tub flange and the sump mounting area have sharp edges.
  • Have a helper to move and tip the dishwasher; never let it rest on the door.
  • Bail and sponge water from the sump before tipping the unit, or it will run into the control board.

Tools and Parts You Need

  • Phillips and Torx screwdrivers
  • 1/4-inch and 5/16-inch nut drivers
  • Hose clamp pliers or slip-joint pliers
  • Adjustable wrench for the water inlet fitting
  • Towels, sponge and a shallow pan for residual water
  • Flashlight or headlamp
  • Painter's tape and marker for labeling
  • Work gloves

Step-by-Step Installation

  1. Disconnect and pull the unit Turn off power and water. Remove the kick panel, disconnect the supply line, drain hose and the power leads in the junction box, and take out the screws securing the unit to the counter. Slide it out onto a towel.
  2. Empty the sump Remove the lower rack, lower spray arm and filter assembly. Sponge out every bit of standing water in the sump.
  3. Release the sump from inside the tub With the filter out, you can see the screws or the locking ring that hold the sump to the tub floor. Remove them and note their order. Lift the old tub gasket if it stays on the tub.
  4. Tip the unit and access the underside Lay the dishwasher gently on its back on a padded surface with a helper. The sump is now visible with the wash motor, drain pump, and hoses attached.
  5. Transfer components Photograph everything, then disconnect the wire connectors and remove the wash motor, drain pump, inlet hose and any check valve or heater bracket from the old sump. Lower the old sump away from the tub.
  6. Prepare AJH32598001 Fit the new tub gasket into the groove of the new sump, making sure it lies flat all the way around. Mount the motor, pump and hoses onto the new sump with fresh clamps where the old ones are stretched.
  7. Seat and fasten the sump Raise the sump into the tub opening squarely and, from inside the tub, start every fastener by hand before tightening in a cross pattern. The gasket must compress evenly with no twist.
  8. Reconnect and reinstall Plug in the motor and pump connectors, stand the unit up, slide it in, and reconnect water, drain and power. Refit the filter, spray arm and rack.
  9. Leak-test Run a full cycle with the kick panel off and watch the sump area with a flashlight during fill, wash and drain. Any weeping at the tub joint means the gasket is pinched.

Fit Checks Before You Call the Job Done

  • The gasket is seated evenly in the sump groove with no twist or bulge.
  • All sump fasteners are tight in a cross pattern and the sump does not shift when pushed.
  • The wash motor and drain pump connectors are latched and hoses are clamped tight.
  • The filter assembly and lower spray arm lock into the new sump properly.
  • No water appears under the tub during fill, wash or drain.

Common Mistakes to Avoid

Reusing the old gasket A hardened tub gasket is the number one cause of a leak after this repair. Use a new one.

Tipping the unit with water in the sump Water runs straight into the door and control area. Sponge it dry first.

Tightening one side first Pulling the sump down unevenly pinches the gasket. Work in a cross pattern.

Mixing up hose positions The drain and inlet ports look alike. Label hoses before disconnecting.

Forgetting the check valve If the old sump had a drain check valve, transfer or replace it or dirty water will return to the tub.

Troubleshooting After Installation

Water under the dishwasher after a cycle The gasket is pinched or a hose clamp is loose. Pull the unit and inspect the sump joint and clamps.

Dirty water sitting in the tub Check the drain hose routing and the check valve in the sump; a missing valve lets water siphon back.

Wash motor hums but no spray The motor impeller is jammed or the connector is loose. Confirm the filter is locked in and the connector seated.

Grinding noise from the sump Debris fell into the sump during the swap. Remove the filter and clear the impeller area.

Care Tips After the Repair

  • Clean the filter weekly so grit does not reach the sump impeller.
  • Scrape plates before loading; bones and seeds are what crack sump housings.
  • Run a cleaning cycle monthly to prevent grease from building up in the sump.
  • Check the sump area for standing water after each cycle for the first week.

Compatible Models (Sample)

This part is listed for 36 LG models in our fitment data. Always confirm your exact model number on the appliance's rating plate.

Repair Difficulty and Time

Difficulty: Advanced. Typical time: 2 to 4 hours.

Frequently Asked Questions

Which LG dishwashers use sump AJH32598001?

It is listed for models including the LSDF995ST, LSD795ST4, LDF6920WW, LSDF795ST, LDF7932BB and LDS4821BB.

Does the sump come with the motor and pump?

No. AJH32598001 is the sump housing. The wash motor, drain pump and hoses transfer from the old sump.

Can I replace the sump from inside the tub only?

No. The fasteners are inside the tub but the motor and hoses attach underneath, so the unit must come out.

Is a new gasket included?

Check the package. If no gasket is included, order one; never reuse the old one.

Final Checklist

  • Breaker off and water valve closed
  • Unit disconnected and pulled from the cabinet
  • Sump sponged dry and filter removed
  • Sump fasteners released from inside the tub
  • Motor, pump and hoses labeled and transferred
  • New gasket seated and AJH32598001 fastened in a cross pattern
  • Unit reinstalled and connected
  • Full cycle leak-tested

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