Whirlpool Dishwasher not draining

Whirlpool dishwasher not draining. Here’s what I confirmed:

  1. No air gap
  2. Pump motor runs, pump is working in wash cycle, plenty of pressure.
  3. No solenoids
  4. Check valve removed and cleaned…no problems
  5. Drain valve open, no restrictions in drain line
  6. Inside of dishwasher is clean
  7. The timer is stopping the pump and reversing direction at the proper drain time in the cycle

The only conclusion that I can come up with is that when the motor reverses to drain the basin the impellor is not pumping any water out of the drain hose…I mean not a drop of water is being pumped. This tells me that the drain pump is defective.

Am I missing something?

If it is the pump, should I order the pump and impeller only, or should I order the entire pump-motor assembly? Is it difficult to change out the motor and install it on a new pump assembly?

How do I remove the pump? I did not see any obvious bolts holding it in place…I assume I also need to order a new seal…Am I missing anything?

Thanks!

Here are your parts
Replacement parts for DU890swlt models | AppliancePartsPros.com

Here is a manual
https://secured.whirlpool.com/Service/SrvTechAdm.nsf/2cd44500d572193285256a45004fd9d6/56e33eb0e839a7fa85256a8e00510938/$FILE/4322430.pdf

Soil settler (Page 6 in the manual)?

Have you tried disconnecting the drain hose at the house plumbing and draining it into a pail?
If not you may want to do this just to be 100% sure that the house drain is OK. Hold the drain line securely in the pail and put a towel over it so water does not splash all over.

You say the motor runs in the drain direction so it is probably OK.
I would take the motor pump apart before ordering anything.
Does not make sense that the impeller would pump in wash yet slip in the drain direction but then stranger things have happened.

Thanks for your reply…

Yes, I removed the drain hose from the garbage disposal and pump and it was clear, no restriction in the hose or in the disposal.

I know the motor is reversing, because I watched it go through the cycle…it did stop and reverse…Also, the sound of the water in the dishwasher changes significantly…When in wash mode it is very loud; you can hear and feel the water shooting up inside…when in drain mode there is no water entering the inside, it quieter, but not a drop of water is exiting into the drain hose…

I agree, I am having difficulty understanding why the pump is not pumping any water out when in reverse, but seems to pump fine when washing…

The only thing I can think of is that the drain outlet from the pump, where the diaphram is, is plugged solid…

If that’s the case I need to disassemble the pump to clear out the debris from that diaphragm…

Your thoughts?
Thanks again!

Yes I agree with you that the best way to proceed is to pull the pump apart.

There is no use ordering parts till you can find the cause.