MDB8751BWQ dishwasher insufficient fill, so arms don't spray

[empirical_tuna]

Greetings, ladies and gentlemen. Title pretty much covers it. This Maytag dishwasher installed around 2007 is on its second set of racks. Lately the soap has been partly (and now fully) left on the utensil basket undissolved where it fell from the dispenser and dishes are not getting clean at all.

The water level is well below the heater and the spray arms are not turning.

Today I ran an experiment: opened the door during the wash cycle and added quite a bit of water and closed the door. Got sounds of water spray rotating afterward.

Is there a way to increase the fill time from the programmed 2 minutes? Is there a filter screen at the intake valve that gets clogged? What else should I check?

Many thanks!

[Josh Smith]

check the flow coming out of the fill valve there could be a blockage at the inlet screen or internally. May not be opening all the way not allowing enough water in.

[Guest]

My first thought was the float is stuck 

[Budget Appliance Repair]

5 hours ago, Dr. Horshenschwartz said:

My first thought was the float is stuck 

If float was stuck in an up position you wouldn't get any water at all.

[empirical_tuna]

I disconnected the water valve output hose and attached a two-foot length of rubber test hose from the valve outlet to a bucket. Activated the valve for two minutes: got 6 quarts of water, which is well below the desired fill level in the dishwasher.

Then I disconnected the supply hose at the valve inlet and measured its output: 8 gallons in 2 minutes (1 gallon in 15 seconds). So it's down to the valve or the brass right-angle fitting. I'll take those out next but I'm guessing the valve has an integral screen that has probably gotten clogged.

Is there a good procedure for cleaning the screen or does it make more sense to just replace the valve assembly outright?

[Guest]

18 hours ago, Budget Appliance Repair said:

If float was stuck in an up position you wouldn't get any water at all.

True. Perhaps stuck right at the point of contact but able to break contact enough to get the water he is getting.  Just speculating.  

Everyone loves a wrong guess to get them going on the right answer 

[empirical_tuna]

I appreciate the suggestions from everyone here.

New valve arrived today. This one yields 9 quarts in two minutes, 50% greater than the old one.

Fill level seems better and I'm hearing water spraying rhythmically much of the time (although not 100% of the time when the pump is running. I'm not completely satisfied with the water level but at least on the first wash it seems to get the job done.

I did notice some drips in the motor area so I have a new pump assembly gasket on order. Service manual seems to indicate the entire pump assembly comes out the top so I won't need to pull the dishwasher.