Rockola 440 Read Out Arm Stuck

Hi,

I recently bought a Rockola 440 which was working at the sellers house but when I got home and turned it on, the turntable will not stop (in operate mode) and when I make a selection, the write-in arm responds and rotates. However, the read-out arm does not move and there is a slight buzzing noise from the read-out's hammer coils. I also noticed that the hammer coil closest to the back of the jukebox (on the read out arm) starts to get warm after a minute, I power it down before it gets hot to prevent (hopefully) damage. In it's current state the tonearm does not physically reach the end of the record to initiate the end cycle. I'm guessing because the stuck read-out arm is preventing this?

I ordered the service manual for this machine but until it arrives
does anyone have any troubleshooting tips?

Thanks,
Robert

Hi Robert,
I do not know R/O models well enough--but can tell you in general, that the pulse to that coil should last only seconds. If it's sitting there for a minute, it will burn up the coil.
Check ALL fuses for proper size and type, before doing anything else!
Unless someone else "chimes in", it would be my advise to not do anything, but un-plug the phono, till you have the manual, and have read it-- Ron Rich

Thanks Ron. I'll do that.

Okay so after troubleshooting and reading the manual further, it looks like the micro switches were not aligned correctly with the camshaft.

After adjusting as per manual spec, the read out coil no longer stays energized operating as it should and the magazine motor will now run--but blows the "1.6 28VDC Mech" fuse within seconds. Same deal with the gripper motor-runs for a few seconds then blows the same fuse.

Because I don't have anymore 1.6A fuses I have been using 1.5A ones. I realize that this would be more prone to blowing, but there has to be something wrong here for it to go that quickly.

Would the motors be causing this? How can I check to see if the motors are okay? When I turn the motors manually via the little knob on the bottom of them, they turn easily and do not seem gummed up.


Any help would be greatly appreciated.


Robert

Robert,
The TT motor is running on 117 vac, so. it can not be what is "blowing" the fuse (BTW--a 1.5 amp usually holds in that position for quite a while).
Did you check the brushes and the communtator in the DC motors ? Ron Rich

Okay Ron, I'll inspect them and post my findings. How should I inspect them? Visually and/or measure resistance or continuity?



Robert

Visually-- Ron Rich

Okay,

I took both motors out but only disassembled the gripper motor so far. I'm sure the magazine motor is probably just as filthy.



















It may be a waste of time but I am going to clean the entire motor and see what happens. Just before I took the motor out, I tried running it without being connected to either gripper mechanism or carriage mechanism to see how it would behave with not load--didn't matter, it blew the fuse again


What kind of grease should I use for internal plastic gears on this?


Robert

I would not add any grease to the nylon gears--there is usually enough of the old stuff to smear onto the gears. Adding is dangerous, as you do not know if the new is going to attack the old, or if it will attack the nylon. Ron Rich

Hello,

That motor looks burnt out to me, there are clear signs that it has been getting very hot, I suggest that you try and locate another motor.

Regards
Alan Hood
ami-man
UK

The brushes are shot too.
The one on the right is non existent.

Pete

Thanks for the reply guys.


I ran the machine without the motors and did not blow a fuse. After I cleaned out the the gripper motor I connected it to the machine and within 5 seconds blew a fuse. The carousel motor was worse than this so I am throwing in the towel on any further repair attempts.

Looks like I'm going to need two motors.


Robert