[Q4]

In case anybody is curious.

The motor is absolutely fine and looks to be decently made.

The white plastic bits are the pump impeller.

 

[Q4]

I should probably explain: my headlamp washers have not worked since I purchased my car. Pulled the pump off this morning and dry tested it. The motor spun up nicely. Wet tested it with a cup of water and no flow so obviously the impeller had stripped out and wasn't engaging the motor shaft appropriately.

Have a new pump on the way.