Question about Whirlpool GU1200XTLS Stainless Steel Dishwasher

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Soap scum on dishes and glasses

The GU1200xtl has washed well since I have owned it - just these past four washes it is leaving a soap scum on both the upper and lower dishes. I removed the upper rotating mechanism to check for blockage and ran the unit through a rinse with no soap to see if the jets were working and they are. I am puuting less cups and dishes in the unit and still see and feel soap residue upon the dishes. The jet wash dispenser it full and I have not changed my ditergent from Cascade since using the machine. Can you please help me trouble shoot why the dishes are not coming clean - I wonder if it could be the heater element. By the way it is draining and free of debris in the bottom filter.

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Re: Soap scum on dishes and glasses

These instructions will work for almost any GUxxx series whirlpool dishwasher:

You probably don't have enough pressure from the pump. That's most likely caused by a clogged filter. So start by checking the filters- the easy one to get to is located behind the chopper in the base of the dishwasher. Grab the whiteish tube going from the bottom of the dishwasher towards the back of the dishwasher and get it to spin about 1/8th turn clockwise and then pull up. If that part works out for you, you'll see four torx screws. Don't loose any of these, they cost $6 each. Take out all four and pull the round white thing up and set it aside. You'll see gray plastic now. Towards the front, down inside, you'll find two more torx screws that are smaller than the first four. Take those out and get the two gray pieces they hold down out of your way. The flat one will come out easily, the other one will take some persistence. Once you get that out, you can see the smaller filter behind the chopper. It sits inside a thin groove, pay attention to this groove, as you'll want to put it back in the wrong place if you don't look it over before you take it out. Remove the filter and chopper assembly and clean it off if it's a mess. Then put the thing back together the same way you took it apart.

If this fixes your dishwasher, then you know pressure was your problem. If the problem reappears and you follow these steps again only to find the filter full of food again, then your chopper isn't chopping anymore. This is probably because the end of your impeller is broken off and isn't engaging the chopper anymore. If that's the case, replace the impeller (about $20 new).

To replace the impeller:

SHUT OFF THE ELECTRICITY to the dishwasher and unhook the wires in the electrical connection box. Notice that (hopefully) the white wire connects to a white wire and the black wire connects to the black wire and the green or bare wire wraps around a screw. You'll need to reconnect this back properly when you're finished with everything else.

Disconnect the drain line, either at your garbage disposal or at the dishwasher if you can get to that connection. Watch out for water, it'll go everywhere when you pull this loose.

Turn off the source of water, if you don't have a valve under your sink for this (you'll wish you did) then you'll need to shut off the water to your house. Disconnect the water supply line from the
dishwasher, this connection is underneath the dishwasher opposite the electrical connection box.

Pull the dishwasher out and flip it over 45 or 90 degrees, your choice.

Unscrew the capacitor from the motor assembly (it's the round looking thing with two wires mounted to the motor), but leave the wires connected to it. Put the nut back on the bolt so you don't loose it. This makes getting the thing out easier.

Find the drain pump, it has a plastic tube connected to it. There is one torx screw holding that in. Take the screw off, pull the tube and the white thing with wires out, leave its wires attached. Your model may not have wires here.

Pull the wire connector off the motor. Remember where it went. Pull the two wires off the thermistor, they should be Yellow (with a black stripe) and white. Make a note that these two wires go on the thermistor so you get them back in the right place. Pull the Blue and gray wires off the drain pump. Make a note that these go on the drain pump so you get them back in the right place.

Next, there are three tabs that you need to find and pull out. They are little L-shaped wedges that hold the round gray assembly to the dishwasher. They are located about 1/3rd of the way around the circle, so once you find one, the other two are pretty easy to locate. Do not loose these parts.

Once you get those pulled out, the entire gray assembly can come out.

Look behind the motor for a bolt. Get your socket set out and find a 3/8ths socket. Put that on an extension, and the extension on your ratchet. Slide the socket between the white plastic protector and the grey plastic (it's a tight fit) and take out the bolt. Do not loose the bolt. Leave it in the plastic so you'll remember to put the plastic back. Grab the motor and turn it about 1/8 to 1/4 turn (it will only turn one direction) and then pull it out of its housing.

From here you can access the second filter, the one that isn't so easy to get to. It's probably fine. And now you can see the impeller, it's white and black and attached to the end of the motor shaft.

To remove the impeller, stick a screwdriver into the back of the motor, being careful not to damage the windings. Hold the screwdriver with one hand, grab the impeller with the other hand and unscrew it from the motor shaft.

Install new impeller on the end of the motor shaft, make sure it's tight.

Reverse instructions to put it all back together. Make sure you get the thermistor and drain pump wires connected correctly. White/Yellow to thermistor (little round dodad) and blue/gray to the pump (big thing on the gray part that drains water from the tub.)

Don't forget to re-attach the drain and supply lines, turn on water and check for leaks. Fix leaks. You may need Teflon tape, depending on the type of supply connection you had to undo. If you use plex tubing and connectors, you don't need Teflon.

Do NOT turn back on the electricity until the dishwasher is completely wired back up, closed, secure, and don't forget the ground (bare or green) wire around that screw.

I'm not responsible if you follow these instructions and end up shocking or killing yourself or your dishwasher. This is what worked for me.

Posted on Dec 29, 2007

Re: Soap scum on dishes and glasses

You should check the spray arm to see any food block the water from spraying.

Posted on Sep 27, 2007

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