Page 1 of 1

wurlitzer 3100 mech issue

Posted: Sat Nov 23, 2013 12:04 am
by cmangeng
The mech does not rotate in a smooth motion, it moves in a stepping or pulsing motion. I've lubed as many points as i could find, but may have missed something critical that is causing this jerky rotation. I have reviewed the troubleshooting chart in the manual and this problem is not discussed. Any guidance is always appreciated. Craig

Re: wurlitzer 3100 mech issue

Posted: Sat Nov 23, 2013 9:25 pm
by Ron Rich
Hi Craig,
That's called "the WurliTzer shuffle" --I have never been able to find AN exact cause of that--
Most of the time, I am able to at least reduce that by oiling the clutch ( spring) area--also make sure that you have oiled the center hole in the basket--it has a large felt pad that turns red, when oil is lacking.
You also might check the back-stop pawls--These MUST BE "clean, and DRY"--NO "lubrication", of any kind, should be used here. NOTE--look at these--the factory "painted" them in the proper adjustment place--if moved, re-adjustment is needed, otherwise I clean them with a plastic-safe solvent--being careful not to get any on the records above--I remove the records--)The last place to check, after oiling (with 20 wt. ND oil) is the transfer and mute/play switches--I forget which one--transfer, I think,--anyway, if you watch them while the basket turns, one will be "bouncing"--carefully "adjust" the actuator screw to reduce the "bounce", and it should stop the "shuffle. Good luck ! Ron Rich

Re: wurlitzer 3100 mech issue

Posted: Sun Nov 24, 2013 10:57 am
by Rob-NYC
Craig, in addition to Ron's suggestions, it helps to determine whether this is electrical or mechanical.

On the mute/play and transfer switches the actuator tip should not be in contact with the switch paddle when the switch is in the released position. Sometimes when the contacts on these switches get pitted and erratic, tinkerers will set the actuator screws too far in a misguided effort to increase contact pressure.

On the mute-play switch actuator arm there is an adjustable keeper plate that keeps the roller slightly off the cam surface while it rotates. IIRC there is a similar setting for the transfer switch. The idea was to keep these two arms from "chattering" on the main cam. If these are set too high it can make it impossible to allow the switch actuator tip to completely clear the switch paddles. Given the cam profile I can't t see why these keepers were needed -other than to improve the functioning appearance to other service techs :-)

Finally, from what I recall these later models with an AC changer motor are actually switched by a relay in the junction box. Pitted contacts there can easily cause the "shuffle".

Finally, there is the grim possibility that the gearbox on the changer motor has a faulty gear. These motors are not a rugged as the DC motor for which the mechs were originally designed.

The ridiculously excessive force used to lift a record places a lot of strain on the changer motor. One all the carousel Wurlitzers I've owned I weaken the lift springs to reduce the lift force from over 80oz to approx 6oz for 100-104s and 10-12 oz for the 200's.

That, and the less than ideal tonearm bearings are really the main shortcomings on an otherwise very good mechanism.

Rob/NYC

Re: wurlitzer 3100 mech issue

Posted: Tue Nov 26, 2013 10:17 am
by cmangeng
Thank you Ron and Rob. I printed your instruction and will bring them out to the shop tomorrow and give them a shot. Spent most of today tinkering on the AMI's, the model F was giving me fits today, so I switched back to the 3100 and compared it to my 2910 to see if I could figure out what was going on. The 2910 does not do the shuffle and I could not figure out what the devil was going on with the 3100. Cleaned some relays and looked for other places to lube, but it did not help, regretfully I had not seen your suggestions at that time. Now I'm stoked to give it another try tomorrow. Will have to dig a bit deeper into the AMi manual to figure out their problems, otherwise, I will yell for help again.
Thanks again guys, it really makes this hobby a lot more fun, when you have folks willing to throw you a life ring when your sinking fast. Craig

Re: wurlitzer 3100 mech issue

Posted: Wed Nov 27, 2013 7:59 pm
by cmangeng
Ron, this is actually a 3110, not sure if that makes too much difference, sorry if it does.
I cleaned the back-stop pawls, they were gummed up, they now move smoothly-there position was verified proper per the manual.
Oiled the clutch and the red felt below it.
I could not find the "center hole in the basket" to oil ( I could not find a reference to "Basket" in the manual so I assumed that to be the record carrier, but found no way to lubricate the center even with the records removed). If I assumed the wrong component, please point me to the correct location.
The play/mute switch was verified with the correct overrun, but the transfer switch was a sealed unit, unable to see the contacts to clean or adjust. I tried to adjust the plunger that operates the transfer switch to limit the bounce, but there were no changes in the bounce while slowly adjusting the plunger stop until it caused the transfer arm to lift then jam, so I returned the switch to its original position.

I compared the operation of the 3110 mec.h to my 2910 and noted the 2910 turn counter clockwise for transfer and clockwise during record carrier/selector arm rotation. The 3100 worked smoothly during the transfer operation when the motor was turning clockwise, however is would oscillate between counter clockwise and clockwise during the selector arm rotation. It acts like it is going one gear position at a time, though I could detect any single direction rotation of the motor gear (oscillated ccw then cw) , not sure how it even moved to the next selection, I thought there was a third motor I was not seeing but could not find in the manual. I realize now there are only the two motors and something is misbehavin with the transfer motor during the selection part of its function and I don't know what would cause this.

Always appreciate a kick in the butt in the right direction. Craig

Re: wurlitzer 3100 mech issue

Posted: Wed Nov 27, 2013 8:04 pm
by cmangeng
Rob, I also sent you a pm, but now realize that I need to post to the main thread, just wanted to make sure you knew what I had come up. I will figure out this computer stuff and the jukebox problems thanks to all the help. Craig.

Re: wurlitzer 3100 mech issue

Posted: Wed Nov 27, 2013 8:51 pm
by Ron Rich
Hi Craig,
The "basket" is the record holder--I think the term basket, is what another juke maker called it ?
Anyway--the oil hole is near the center of it. To find it, set the record loading switch to "load" and slowly spin the basket. Use a flashlight (OK--for you guy's across the pond, a "Torch") to peer down the center at the edge of the records. As you spin the basket, you will notice "holes" that allow you to see down under the basket--On the -10 models (-04 models, I think there is only one?), I am not sure how many "holes' were used--but on the -00 models, three can be seen. ONE of these will be "larger", then the others. "Center" this one, at your bellybutton, then look down below, and you should see a red felt (if dry--brown if oiled). I saturate it several times with SAE 20 wt. ND oil--Play a few songs and saturate it again--it will "suck-up" a large amount of oil--and, it will take sometime for the oil to "get down", where it will do some good. Ron Rich

Re: wurlitzer 3100 mech issue

Posted: Thu Nov 28, 2013 9:34 am
by cmangeng
Ron, I found the lubrication point....I think. There is one dime sized whole just off center from the basket hub (center). When I oriented the hole towards the front of the machine, I found a possible lubrication point. I was looking for a larger felt towards the central shaft area, but this particular area was a small 1/4" felt, I originally thought it was a screw head. It was not red on mine, so it probably had oil in it, but I added more and it took it.

It is official this machine is possessed. I spent and hour or more watching the changer motor while I manually tripped selections. I observed a smooth operation while it transferred records from the basket to the turntable. The problem started when it began to scan for the next selection, it commenced a ratcheting rotation of the selector arm. The motor pinion gear (from the gearbox) that joins the gear and ratchet wheel assembly did not move, not one tooth. The small gear that is on the bottom of the motor (it does not connect to anything) rotated ccw then cw in short bursts each direction; it constantly oscillated like that through the entire scan process. I can not figure out how the selector arm is rotating at all. If the motor gear (the one that comes out of the gearbox) does not turn, nor do any of the gear and ratchet wheel assembly components, then the selection arms should not turn.....right??
As I mentioned previously I have a working 2910 and I have observed the changer motor rotating one direction for the transfer process and the other direction for the scan process. Them mechanisms look almost identical. It seems the 3100 should function this way also, but for some reason it is not and I am at a loss....short of an exorcism.
This has been referred to as the Wurlitzer shuffle, I even played a Micheal Jackson song to see if I could teach it to moon walk, but it has a one track mind. I really need so advice so I can teach this thing a new dance step. Thanks again, Craig

Re: wurlitzer 3100 mech issue

Posted: Thu Nov 28, 2013 6:05 pm
by Ron Rich
Craig,
I think you located the oil hole mentioned I before--
Check the "selector crank", and "stopping switch" adjustments (oil associated "bearing race", and levers) (check the switch itself too), as per manual-- Ron Rich

Re: wurlitzer 3100 mech issue

Posted: Fri Nov 29, 2013 9:47 am
by Rob-NYC
The problem started when it began to scan for the next selection, it commenced a ratcheting rotation of the selector arm. The motor pinion gear (from the gearbox) that joins the gear and ratchet wheel assembly did not move, not one tooth.


Craig, what you are describing here is not possible. There is only -one- motor that handles all changer robotics. If the carousel is turning -the motor is turning it.

Also, the action of the two backstop pawls prevents any but the most minor reversing of the carousel....IF they are working properly.

Are the carousel and selector crank locked together? The crank is what hits the pins. One easy way to check is to hold the crank and try gently try to move the carousel clockwise. Both should try to move at the same time. IF the carousel has at some point been forcibly turned or the carousel has been removed, the "pip" that engages the two will not be in the spring loaded catch under the carousel and that can cause hunting along with always playing the wrong selection.

When the motor is 'stepping" is there any action on the two cam switches? There should not be.

From what I recall there are a mix of AC & DC relays and the changer motor is operated by a relay. The correct relays (AC vs DC) must be in the proper sockets. It may be helpful to pop the covers off the relays (mark them) and observe which relay is stepping in time w/motor. If you find that happening you'll be able to trace it power sources back and find the trouble.

I haven't had a later model Wurlitzer since 1988 -but this is one odd problem I wish I had in front of me.

Rob (recovering from thanksgiving in) NYC

Re: wurlitzer 3100 mech issue

Posted: Fri Nov 29, 2013 11:23 pm
by cmangeng
Rob, I thought what I observed was impossible too, which is why I joked about the juke being possessed. My wife would not let me work on the 3110 yesterday (Thanksgiving) and I have not had a chance to check the adjustments Ron recommended. They are on the slate for today.
If the cam switches that you are referring to are the transfer switch and the mute switch, the yes, the transfer switch is being pulsed during this ratcheting motion.
Yes the selector crank and record carousel/basket are locked together. I can turn the crank arms which turns the record basket. There is not hunting during the selection process, just a stepping/ratcheting action, like its going one selection at a time. The carousel does not seem to reverse. I cleaned the backstop pawls like Ron instructed and they are now working smoothly, but it did not correct the problem. When the pin is contacted by the crank arm it will bounce a little, then go into the transfer mode and move the record to the turntable.
The manual appears to use 3 different names interchangeably in their explanations for the same switch (stop switch, reversing switch and carriage switch). This switch function and the adjustments associated with it are what I am going to check today as Ron recommended.
I could send you a short video of the mech. during this operation, but don't know if can be done on this site and i would have to research how to download it to the site, if its possible. I can send it to an email address, if that is allowed. Hope you all had a great Thanksgiving and Thank you, Craig

Re: wurlitzer 3100 mech issue

Posted: Sat Nov 30, 2013 3:54 am
by Rob-NYC
If the cam switches that you are referring to are the transfer switch and the mute switch, the yes, the transfer switch is being pulsed during this ratcheting motion


Ok, I know what is going on now. The main cam is being dragged clockwise when the carousel scans and the switch actuators are then moving off their peaks. When this happens the changer motor acts as if the cycle is just finishing returning a record to the carousel and entering the scan mode. This process repeats and the carousel lurches till the crank hits another pin.


The main cam ---must not turn when the carousel is turning---.

The likely cause is old, gummy oil that is acting as a sort of fluid clutch.

Diagnosis is the easy part....Fixing it can be a bitch. You can try heating the area including the spring and ratchet on top of that cam and see if you can get some heat under it as well. Don't overdo the heat (no torches) just a heat gun and make it just too hot to hold onto.

If you get it warm enough it should be able to slip properly and then you can start adding a very light oil to loosen up the gunk in there. You'll probably have to do this several times.
The way I'd proceed is to remove the pin memory -but leave it connected. manually trip a pin to get the mech scanning. Then try to hold the main cam still so that the oil is worked-in. Watch your fingers and it will be hot from the heat gun.

Hopefully this will fix it. You don't want to take that area apart. I replaced a fractured main cam on a 2800 in back in 1986. Once was enough.

Rob/NYC

Re: wurlitzer 3100 mech issue

Posted: Sat Nov 30, 2013 5:24 am
by cmangeng
Rob, I tried holly water today but it did not work, I will try heat on it tonight. :mrgreen:
I have lubed everything that I can get to. Is there a special location to place oil so that it gets directly to this problem area. It is possible that I missed a critical lubrication point. There is no lubrication guide in my manual or on the machine, which is a bit frustrating, especially since there are multiple location that should not be lubed.
I did all Ron's adjustments today, which took the initial bounce out of the carriage when it made contact with the selection pin. I also lubricated points that were recommended. I am concerned that I have missed a significant point of lubrication, which others may have missed in the past to cause this malfunction.
I will disconnect the pin selector and use a heat gun as you suggested. I will git-er-done tonight, but would love to know where to specifically put the oil.
Thanks again for all the help, Craig.

Re: wurlitzer 3100 mech issue

Posted: Sat Nov 30, 2013 7:08 am
by cmangeng
With heat I have banished this demon. :mrgreen:

Rob, I followed your directions almost exactly....maybe a little too much heat, set off the smoke detector, there was no smoke and I did not smell any, but the detector did. The important thing is that it freed up the shaft. I still do not see how the selector arms were able to move with no gear movement at all. I put my fingers on all the gears and nothing was turning except the small one under the motor and that one oscillated in both directions.
I oiled every nook and cranny and I might have even got some where it might do some good.
I was absolutely ecstatic went it went into a smooth rotation. Wow...how the heck did you figure that out.
My only concern was when I put the pin bank back on; the motor would not run at all. I remembered a thermo trip in the schematic and found the motor had gotten quit hot from the continuous running during the heating and oiling process, not to mention the heat I had applied to the main shaft. After it cooled down everything worked fine.

Now it looks like I just need to rebuild the amp and it will be a gem. Only one channel works and the other channel has a bit of distortion in the sound. This amp came out of my 3000 since the original amp in the 3100 did not produce any sound at all. Has the old cartridge but a new stylus.

Thank you both, Rob and Ron for all your help. Next topic will on the AMI's, but I will discuss that in another thread. You guys are awesome, Craig.