Remove the upper spray arm from the maytag jetclean MBD9150

SOURCE: Maytag MDB9150

You just have to gently pull it doward.  It should unplug relatively easily.  To reinstall it, just plug it in it's shaft.
Roger

SOURCE: MAYTAG JETCLEAN QUIET PACK

hi Replacing the Door Gasket

If water leaks through the dishwasher door, the gasket is probably faulty. Open the door and examine the gasket. It should be soft and resilient. If it's worn, cracked, or hard, it should be replaced. 
Once the gasket is in place, check it for fit against the door frame. It should fit tightly with no cracks or bulges between the gasket and the frame. If necessary, tighten or loosen the retaining screws, or refit the gasket in the clips or the door channel. Then run the machine through a washing sequence and check for leaks. 

If you spot a leak, and the gasket seems to be properly in place, try adjusting the door latch. The trick is to position the gasket against the frame of the door without flattening the gasket or squeezing it too flat when the door is latched properly. Adjust the latch or the gasket until it fits snugly against the door frame.

SOURCE: how do you remove the lower spray arm from a maytag mbd4100 dishw

go to managemyhome.com and type in your model # and get your manuals.

SOURCE: my maytag dishwasher lower and upper spray arms

Pour 1 Cup of Muriatic Acid (Can be purchased at your local Pool Supply Store) into the bottom of the washer and a little in the soap dish. Run the Dishwasher through 5 cycles. Check to see If this helps. If not Try the same process with CLR house cleaner.

SOURCE: Maytag dishwasher with a spray arm that is stopped

We have a dwu7400 so i'm not sure it is the same, but above the top arm you should see a serrated ring (looks a bit like a flower petal) and that should spin off and the arm should come with it. There's a snap that holds those pieces together that if you squeeze it with your fingers you can get it out. Just reverse that to put it back together.