๐ช๐ง Technical | Faults | How-to's โโน
I'm not really into the schematics of the electronics, but since the grinder did start, though sporadically with xx nf, I'd guess it should work with the 0.68uf one. It might be a bit off with the timing of the timer, but you can just adjust it down.
I used a one of these, with a little insert...