Squeak screeches to a halt

The last few times I've been quilting on my Pfaff GrandQuilter 18.8, it has been misbehaving.  It would occasionally start squealing.  Metal on metal.

I oil this lovely machine religiously, likely over-oil.  So when the squeaking started, I'd add a bit more oil and it would stop squeaking.

Today, there were only whispers of squeaks and mostly good behaviour, right up until it stopped. Quilting along, it has a harsh hum and the needle will no longer go up or down.  The lights indicating whether it is in needle-up or needle-down and if it is in the start stitching position, are flashing. Quickly turn it off so it doesn't burn out the fuse.  And unplug.

Try turning the hand wheel, and nothing moves.  Rock it back and forth and eventually it will move again.

Plug it back in.  Starts OK, and will even perform a needle-up cycle.  But it's working too hard.

Take the cover off the belt at the back - not that I can see anything, and nothing looks out of place.

I was working on my MIL's quilt project that we found earlier in the spring.  Had been hoping to get it finished up and to her before the new year.

Hopefully I can find someone to service the machine.

Sad day.