Rock Ola problem

I have a Rock Ola which was built in the late 60's, I believe. According to
the plate on the back, it is a model 450.

It suddenly has a problem in loading the 45's. When you punch in a title,
the large wheel on the right starts turning and will turn until you unplug
the unit. The wheel on the left which loads the 45's does NOT turn during
this process. Usually they seem to work in sequence.

I'm wondering if it is a physical problem or is there some reset mechanism
that might help it.

Thanks for any help you can provide!

First, the right side arm and basket do not rotate until the selection
is made by the arm on the left side of the pinbank.
When the arm on the left rotates, it is searching to complete the
circuit for the selection process. Problems can be caused by a blown
selection circuit breaker or fuse, a dirty slip ring assembly\, the
wipers and contacts, dirt in the large molex plug that comes off the
pin bank, a bad stop or write in relay at the power supply, dirty
contacts on the ADR relay in the credit unit, dirty contacts in the
keybank, or a break in the wire harness going to and from these items.
If you go through these basics and still can't get it working, you will
ned the service manual. If you don't have one, contact me direct.
Charlie