Looking for a quick bit of feedback before I break out the multimeter and start testing electronics and looking for issues with my procon.

My Astoria has a water cooled motor and procon pump. The pump was rebuilt professionally about 2 years ago. Issue is that when it was reassembled a piece of o-ring got stuck in the pump and locked it from turning. for a year the owner didn't know it was stuck and was pulling shots at line water pressure (about 5 bar)

I got the machine, removed the pump to send it out and noticed the bits of o-ring, flushed them out, and started using the machine. In the past few months its has started sticking on startup. Not every time, and a few rocks of the switch and off it goes spinning. When it sticks it humms.

Whats the general thoughts out there? Start up cap fried from a year of being stuck? Brushes and armature burned from being stuck? pump damaged from o-ring wedged in it?

Obviously visual inspection on a procon is hard but seeing how it spins without the motor is easy, as is testing the capacitors output with a volt meter... I just figured I'd give a whirl on here before I gut my machine and perhaps go without espresso for a week waiting on parts.

Thanks!