Kenmore Dishwasher Repair
Mineral buildup problem - Owners live in an area that has bacterial iron in the water. They have filters in the basement that take out most of the mineral, but not enough to keep it from building up on the walls of the dishwasher and probably inside the mechanical parts as well. Can they run something through the dishwasher that will help clean it out?
Glisten is the most common product and fairly inexpensive. Pour it in your dishwasher let it run a cycle. It will take a lot of the soap scum, mineral sediments, etc. out of the tank and the wash arms.
For the hard water scale, try pouring a little vinegar in the run cycle and see if that helps with your Kenmore dishwasher repair.
Kenmore Portable Dishwasher, Model 665.17761890
Dishwasher is leaking from underneath
Being a portable dishwasher these are a little easier to work on because you can just lay them on their back or side. Tilt the dishwasher and look on the underside. If you see a sign of where water has been leaking between where the motor goes up into the pump assembly then that's probably your issue. There is a set of seals and impellers in it that can fail and then water will drip onto the motor and then onto the floor.
If you're sure it's not something in the connections, it sounds like a motor seal leak. You can either replace the seal and the impellers that move the water around inside the machine or you can get a new complete pump assembly and that should solve the issue.
It's possible that it's a leak from the tank, but they are really durable.