The unit would make 1 good cup then eventually it would sound like it was going through the motions but you would get a partial or no cup of coffee.
I didn't know if a could remiss this but wanted to try. at the store i figured it was broken anyway or the staff would have grabbed it up right?? and I had been wanting to tear apart one of these to know what makes it tick. If I could fix it HEY saved $100.
Step 1: Google It and Begin Teardown
I am not going into great detail on the cover removal because this is not covering all Kuerig brewers and Youtube has many great vids on exactly how to tear into Keurig brewers it is where I found my info.
That being said if you purchased your brewer new the best plan is to return it if you are having issues either to the retailer or Keurig. This tear down will definitely void any warranties. If you decide to go ahead note again removing the top panel may disfigure your brewer slightly.
----- do not work on your brewer while it is plugged in!!---
Step 2: Gate Cover and Plumbing
To hit the high notes:
Lift the handle and you should see some hardware at least 2 screws holding the lift gate cover on. Remove these and the lift cover can be slid out. It can be a bit tough as I recall.
Under this cover note the relatively large supply water line. It seems to be made of silicon type surgical tubing.
I have seen quick fixes that say clear the exit spout with a wire or tooth pick etc..
1. With a supply line this big you would have to using puddle water for months to clog this thing up.
2. All you are likely to do is damage this supply elbow and cause a leak. So if you poke around with a sharp stick you have been warned.
Everything up top so far looked good now to the bottom.
Step 3: Bottom Inspection
This step is pretty straight forward remove the screws you see and the cover should come off no surprises.
The main pump is the white unit seen in the pics above. This is what does the cup fill pumping. All the connections seemed in order and I found no pin hole in the lines that could be causing cavitation / pumping issues.
I was left with complete cover removal... Find a good video.
Step 4: Side Cover Tear Down
If you proceed and get the side covers off you will find that this brewer is not that complex. It does sort of look like a sci-fi warhead but this is just the boiler tank and probes.
Breakdown of how it works:
The boiler tank can be seen in the top left portion of the pic above. It is a clear tank with electrical level probes that reach down to various depths of the tank.
When you select a cup size the brewer fills the broiler tank (using the 2 upper pumps in the pic) until the probe level for you size is made. Then the water is heated.
Then the fill pump activates after the boiler tank has reached it brew temp. The fill pump (seen in the bottom right) pumps until the minimum water level switch is cleared.
Step 5: Solution??
A design flaw of these machines is that the upper valve that is mounted above the filling pump is prone to leak. If you look at the last pic again it will leak
1. On the power transformer
2. On the dc motor of the fill pump
The motor shaft for the fill pump of this Machine had a rusty spot on it. I was able to spray motor contact cleaner into the unit and spinning it by hand got it feeling much better.
If this didn't work you can buy these pumps online ~$20 if I recall.
If this did not work for me I had planned to get a fish tank pump and fit it to the unit maybe make a steam punk style exposed inards brewery.