Can anyone with a System 1 Gottlieb chime unit:

http://www.pinrepair.com/sys1/s1chime1s.jpg

1. Tell me the part number for the coils used.
2. Measure the voltage supplied to the coils.

Thank you.

Thanks for the information, I appreciate the time. That makes the malfunction harder to diagnose.

The coils are the correct part number A-17876. They ohm out correctly on the bench.

Applying power from a 24V supply to them however does not make them chime as they should. Two chime weakly and one not at all. Very strange.

Not so obviously here. I bought the unit used and have not tore it down to check yet. Should it not function well, it's probably monetarily better to return it instead of rebuilding it.

The plungers do rest on a foam pad.

I just bought a refurb kit from pbr. I'll try it out.

No, the chimes and rods look clean. The sleeves were coated with fine black dust-dirt.

Flicking the chimes with my fingers causes a nice chime ring.

All chimes seem weak but the lowest tone chime very rarely even hits. Watching the plungers in action, the chime kit seems to be supposed to work in the following way.

Steady state OFF is sitting down on some decent looking beer seal.
Steady state ON is sitting up with an air gap between the top of the plunger and the chime bar. I assume this is by design so that after striking the chime plate it is allowed to ring (can anyone confirm this?)
Transiently when turned on, the plunger overshoots its steady state on position to strike the chime bars. This is happening weakly for 2 of the chimes and not at all for the lowest pitched one. For the lowest pitched one the plungers flies up but never strikes the chime. It's steady state ON position appears to be the same as the other two though.

The coils themselves look clean and unburnt and ohm test out to spec.

Well, the refurb kit was not helpful. Same response as before.

Since the coils all test fine and 3 failed coils that all have the same in spec resistance seems unlikely, I have to assume this unit perhaps is made to operate at higher than 24-25V?

No, the bars are fine. I can strike them manually and they give a nice ring.

I can visually see the operational problem. The plunger seems to fly up quite nicely but does not overshoot its on steady state position. It does not actually strike the chime.

There appears to be no physical impediment. Powered off they slide easily up to touching the chime bar.

They are in the top half. The new sleeves have a small ridge that wedges between their plastic assembly (which comes out the side of the unit with the wires) and the top. I winder if somehow it has the wrong length plunger rods?