GDF640HSM0SS GE Dishwasher lower spray arm not working

[Captain Cripple]

Model Number

GDF640HSM0SS

Brand

GE

Age

1-5 years

This was the best dishwasher I'd ever used until the lower spray arm suddenly stopped working, as evidenced by lack of cleaning of inverted pots and such on the lower rack. The top two racks continue to show excellent performance from the upper spray arm.

When this started, I found an O-ring at the bottom of the unit after a wash cycle. We can't match it up to any items washed and are baffled as to its origin. OD - 1.275", ID - 0.925", thickness - 0.140", edges are right angle, not rounded. If'n I had to bet my last dollar on the matter, I'd bet the O-ring is related to this strange malfunction.

I've cleaned both filters with no resolution.

Help is much appreciated.

Cheers!

 

[Jake]

Is this the O-ring: https://www.repairclinic.com/PartDetail/O-Ring/WD01X22825/4466491

That one is located underneath the float mounting tube.

Here's the video of the float mounting tube and you can see it at the 2:25 mark of the video:

 

[Captain Cripple]

Many thanks for your reply, sir.

I don't think that's gonna be it - it looks rounded edge, not sharp edge like my mystery O-ring, which, again, is of uncertain origin re: part of dishwasher or not.

I got the unit new and have never engaged in any tool-required disassembly, so I don't think that's the culprit. Photo of mystery O-ring attached.

Seems a mechanism that diverts flow to the bottom is not functioning, but this is my first such dishwasher adventure and I don't know nothin', see.

Thanks again for the help.

 

[Jake]

Ok, that's the only O-ring I see in your parts diagram, sorry.

It may have come off another part below the lower spray arm, but I don't know which one. Hopefully another tech or member that's seen this O-ring loose like on yours can shed some light on where it came from.

Other than that, you may want to contact GE at 1-800-432-2737 to get a authorized GE tech. to come out to see where it goes.

 

[Captain Cripple]

Thanks again, Jake, but the whole reason I'm here is to avoid that whole authorized tech thang

Again, I've far from certain that O-ring is part of the dishwasher and after a careful review of parts diagrams, I'm less certain than ever.

Howzabouts this - let's forget that dang O-ring ever existed and focus on the symptom - what are the typical causes of loss of lower spray arm function? Lower rack dishes not cleaned from below, all other function fine, no error codes thrown.

Cheers!

 

[Captain Cripple]

ADDENDUM - I just ran a cycle on lower zone only setting - same result. Lots of rain from above, but no upward spray from the bottom. Lower spray arm clearly not functioning.

 

[Jake]

Yes, it could be the diverter then or the diverter check ball stuck blocking the lower spray arm inlet port from the circulation motor.

Start reading at pages 58 and 59 Diverter here: https://drive.google.com/file/d/1csheGsbSmPFRON5ThkhhwfvZ6saWoxHc/view?usp=share_link

On page 58 make sure the lower spray arm port is not clogged/blocked preventing water to the lower spray arm.

Also make sure the diverter check ball is NOT stuck blocking the lower spray arm input port like you see on page 59, that diverter check ball should be resting at the bottom of the diverter, when the dishwasher is not in use.

Here's the diverter assembly for your model:
WD19X25278 Diverter Asm Kit


Here's the video to access it:

 

[Captain Cripple]

Suspecting a stuck diverter ball, I tried a cleaning treatment using CLR, but to no avail. Thanks a ton for the service manual, I should be able to take it from here. I can't hardly imagine a situation where a not-so-old unit that's not leaking needs the part replaced, but I'll see if I can ascertain if the ball is stuck. I suspect resolution is, one way or another, not far away.

I'll be sure to report back with the outcome. Thanks again, sir.

 

[Jake]

Ok, sounds good, yes keep us posted.