My problems began with the gradual collection of residue (detergent?) on the upper rack sliders. Lately the unit has not been washing & rinsing the upper rack very well. I did a lot of reading on the forum here (great resource btw) and disassembled the unit all the way down to the chopper using the Whirlpool manual frequently referenced. I did find a lot of deposits, some rather large, and cleaned everything out before re-assembling.
I made sure the drain was free of obstruction and verified it was emptying the unit completely. And getting the chopper back in there was a real pain.

No improvement. Dishes still have food residue on top rack.

Another problem I discovered is the unit is filling up until the overflow switch is triggered. I discovered this by letting the unit fill and then pressing on the overflow float before the cycle begins. I can hear the switch disengage. At first I lifted the float only to find it was already out of travel.

My local appliance guy and I are stumped because the unit continues to operate even though the switch is tripped. He says that should never happen and I should seek Professional help.

We seem to think the upper arms are not getting enough pressure, but are not sure where to tackle the source of the problem(s).

I'm pretty confident I will get the answer here.

Its likely the wash motor impeller assembly, KitchenAid/Whirlpool had some issues with wash motor impeller assembly wearing out prematurely, and causing the loss of wash power through the upper/lower spray arms.

You can either order just the wash motor(more work to install), or the complete sump/wash motor assembly(easiest to install).

But the repair manual you have will show/tell you how to install both either way.

Here's the cheapest price I found on your wash motor assembly:
Manufacturer's Number: 8534942

8534942

Here's the sump/wash motor assembly for your model:
Manufacturer's Number: 8535150

8535150

Jake

__________________
Appliance Repair School 1987-1988
Star Appliance Tech. 2 yrs. 1988-1990
Wards Appliance Tech. 11 yrs. 1990-2001
Sears Appliance Tech. 4 yrs. 2001-Oct. 2005
Jake's Appliance Repair Nov. 2005-present

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Jake,

Thanks for the prompt reply on the water pressure issue.

Any ideas on why the unit is "overfilling" (or is it)? Does the fill operation use a timed or mechanical dependency (float switch)? My understanding was it should be timed and the overflow float is there as a stopgap measure. But if the float is the device used to switch off the fill (like a toilet) then I am mistaken.

It depends on the water pressure, if you have above average water pressure then it may fill faster, thus making the float stop the water before the timed fill stops it.

As long as its not overflowing onto the floor then its fine.

Jake

__________________
Appliance Repair School 1987-1988
Star Appliance Tech. 2 yrs. 1988-1990
Wards Appliance Tech. 11 yrs. 1990-2001
Sears Appliance Tech. 4 yrs. 2001-Oct. 2005
Jake's Appliance Repair Nov. 2005-present

If you need more repair advice help on your appliance, click Here

Look-Up & Order Parts

Shop Home Appliances