So I fixed a Silvia with slow water extraction. There is another possibility that happened on the machine I fixed. If the intake to the pump is loose, it can suck some air in. This will cause intermittent slow extraction.

So I think I'm back in action here. I did several backflushes, and eventually they started to produce more water. I probably did 20.

My flow was a little better, but not back to where it had been.

I took a break to make dinner, then tried another backflush, and then the group head started to really work fine. So maybe I had loosened up some accumulate scale in there and then it finally cleared out.

I did three more flushes and I seem to be back in business.

I didn't use any powder for the backflushes - just water. I do think I should maybe get some cleaning product in there when I have a sec.