[Jukebox-list] Seeburg C not cancelling pins - A side only

[Aaron's Email]

Guys,
Here's an update on my C not cancelling pins on the A side. I pulled the
mech and started to look closely at the cams as per Ron and Wes's
suggestion. However, I still couldn't shake the feeling that something was
seriously wrong with the cancel coil on the contact block. So with the mech
on my bench, I started putting the mech through it's paces while trying to
watch what it was doing as best I could. I found that when playing the B
side, the cancel coil would energize fully and shoot the plunger all the way
out of the brass sleeve as per spec. In fact, you can even hear the coil
energize for a split second when the SC and C switch contacts are made to
energize the coil. However, on the A side, the same making and breaking of
SC and C happens, but the coil won't budge. I checked the voltage to the
coil and found that juice was getting TO it, but the coil still wouldn't
move.

With the mech at rest, I manually shorted SC and C together - still nothing.
I switched the reverse switch to the B side and again manually shorted SC
and C and the B coil popped. Cool.... but why not A? Again, I put my meter
on the leads to the coil and it's definately getting voltage. Now here's
where it get's REALLY bizzarre! Thinking that perhaps the brass sleeve of
the A coil was interferring somehow with the plunger's ability to move, I
put a thin soldering pick into the sleeve and manually pushed the plunger
up. There was no binding or resistance at all. I don't know what made me do
this, but I put the mech back into automatic and advanced an A-side pin.
What I wanted to try and do was to insert the soldering pick into the brass
sleeve just as the mech was going to automatically come to rest and cancel
the pin and see if there was any binding once the coil was energized. What
happened next was strange. With the pick in the sleeve, and the plunger
pushed up perhaps 1/4 of the way, the coil energized and cancelled the
pin!!! I pulled the pick out, tried a different selection and nothing
happened! No coil movement at all!

With the mech at rest, I manually shorted SC and C together again and
nothing happened. I pushed the solder pick into the brass sleeve - shorted
the switches - and the coil came to life!!! Thinking that I may be shorting
something by using a metal solder pick agains the brass sleeve, I tried the
same test using a plastic alignment tool. Same results - the coil works!

What's up with this?!?!