The power of advertising
Well done on this one Mike, and as several members here have proved, it's surprising what is still out there if you pop an advert up.
Firstly sorry for the late reply, if only the computer was as reliable as my old hoover 1100, I'd have chipped in before.
I agree the control panel is a lovely blue and red contrast, I notice like mine there is no hoover badge on the door, so I wonder what date that comes from, it's black design like mikes, but the original one dark red one piece keyplate.
So onto my thoughts, I agree with Alans suggestions, try tripping the pressure stats etc. The keymatic timer works using a series of impulse paths, so in order to index on, a circuit needs to be completed, such as a pressure switch, thermostat, internal timer or one of the keyplate switches. So the timer sounds like its waiting for a circuit to be completed, so thats where Alans suggestions would be a place to start.
But also to add, on the side of the timer where the cable comes out is a little viewing window where a disc with a number rotates showing which timer increment the switch has reached, 0 being off, I think it's a 40 or 45 segment timer, so again this may give a clue as to where the machine stopped and a clue as to a fault.
Next idea, I did have a real rust bucket of a keymatic years ago, long gone now, but the timer just hummed, but the cable drive to the indicator tape looked rusty and very stiff, so I disconnected it and the timer whirred into life.
Finally, there isn't a solinoid in the timer, just one motor that both times and advances, there is a large resisitor that reduces the motor voltage whilst timing, frequency is the same so the rotation speed is constant. For rapid advance the full voltage is put across the motor, causing the rotor to slide laterally in its bearings against a spring, engaging the advance gearing. This is what we found with Ians timer, the one pictured above, a few drops of oil freed it up and it then advanced away beautifully. It does seem odd that a sleeve bearing is fine to rotate but not to slide, but I've seen it on Ians and a couple of others. The real hope is that your timer case is nut and bolted together rather than rivited.
So Thats my thoughts, hope they will be of some help, oh and of course I'll chip in to the door gasket fabrication consortium.
mathew