Kenmore dishwasher fill time varies ... & cleaning quality varies, too

[wieb]

My dishwasher fill time varies between one of two times, nothing in between.  

When the dishwasher fills for 2 min 50 sec (at start of cycle & rinse cycles), it works perfectly.

When the dishwasher fills for 1 min 40 sec, the level is low, the pump surges/cavitates as it is starved, and it leaves soap & food particles, especially on the top rack.  I can add about 3 quarts of water manually at each fill cycle and it works perfectly.

It can work well 2 to 3 times in a row, and then not fill properly for 2 to 3 times.  It doesn’t matter which program I use; I almost always use “Normal” wash.

It feels like a control problem … too repeatable and too precise at each of the two different times.  I need some help.  Any advice would be welcome.  Thanks.

wieb

Model 665.13759K602

[JWWebster]

Its not a control problem, it is a bad water valve. Those valves are metered and specifically engineered for a timed flow rate. Replace the valve. And when you replace it buy the exactamundo.

[wieb]

Thank you so much for the quick feedback!   
I have the $40 valve, exactomundo, unopened, sitting right next to me.  I was planning on returning it because I am now "almost" sure it is not the problem.  I can hear the valve opening and closing and I can not get over the fact that it is so repeatable ... exactly 1 min 40 sec or 2 min 50 sec ... I can't understand how a bad valve can control time when it has no timing function.

I can understand how a damaged or plugged valve can interfere with the accurate metering of the incoming water, but the valve is closing at precise times and I can hear it. If the valve was damaged or plugged, it would still close at the same time all the time, right?  I was hoping to get my money back and buy the real part I need ... maybe the electronic control board? I don't know. Can you help me understand how the valve behaves like this, closing at different times?

Thanks.
wieb

[JWWebster]

Hard water causes friction and restricted water flow that is intermittent.

[wieb]

Thanks for the help, JWWebster.

One more question: Where in the dishwasher (what part) does the timer function for the inlet valve ON/OFF function reside?  Is there a separate timer (I don't see it anywhere in the schematics as a stand alone item) or is it part of the electronic control board?

wieb

[JWWebster]

On these newer whirlpools during the first five seconds,
the drain motor turns on and the fill valve is activated. This purges the
soiled water from the accumulator and begins to
add fresh water. For the remaining five seconds,
the drain pump is turned off, but the fill valve remains
activated to bring wash water up to proper
level. So all of that is done with the control. I couldn't get your model number to work but I do have a late model whirlpool repair manual. Look through it an on page 4 shows the theory of operation. This should give you a better idea than I could. Dishwashers are not me fav subject. Their are others more qualified than me on these latest wonders.

Late Model Dishwasher service manual

[Repair-man]

Located the Tech Sheet for this one.