Wurlitzer 2150 uneven/jerky movement of record arms

Thanks to several people on here (you know who you are!), I've been spending too much money on 45's for the past seven months. It has have gotten a bit out of adjustment, as one would expect while things 'settle in' after years of serving as a mouse habitat in some shed somewhere. I've held off on making any significant adjustments since it sounded good and generally worked. Plus, the boss is not a fan of the sides. Even I have to admit that the sides have crossed the line between 'vintage patina' and beat to hell. So, I knew I would be taking things apart to veneer up some new sides for it. The bad news is that it appears one must disassemble/remove every part of the jukebox to get the sides off. The good news is that it means I will have free, unabated access to the record changer mechanism to get things in tip top shape. Sorry for the long winded preamble to my question.

At times the record arm will move a record into position and it is smooth as silk. Other times it seems to pause, shoot up in a very jerky manner. It is inconsistent but seems to be localized to the right arm. When it shoots up, it can come a tad late, after the tonearm is released causing the ton arm to bounce about 5 seconds into the record. I assume it is catching or binding somewhere. Any obvious candidates to start my search?

Another sporadic problem is the selection mechanism. Sometimes you have to hit a button combo multiple times before it actually selects. Again, any typical culprits?

As always..Thanks Brooks

(By the way, was there a typo in the original specs for the record raising arm. I assume the spec should have been "Force of record lift arm 1.50 oz but was incorrectly written as "Force of record lift arm 150 lbs)

Hi Brooks,
Since you're a bitchen--I anina gonna help--like the ladies too much---
OK, OK, my guess would be that the backstop pawls are dirty, and the lift arm was not "centering" all the time--could also be ( can't recall which ES is on that model) that the ES is not correctly "centered", OR, lack of oil, problems--?? Ron Rich

Brooks, what you are experiencing is the inevitable result of doing things piecemeal. You can't do a "Windex overhaul" (as I call it) on a machine that lived in a barn for decades, i've bought enough to know that fact.

The direct causes of lift arm binding are:

1) Stuck or gummy brass guide rollers. These are under the deck and engage thick area of the lift arm near the elbow to center the duckbills in a mounted record. They -must- turn freely and really should only lightly engage the lift arm, if at all.

2) Bent separators that work against the lift arm and cause it to conflict with the aforementioned rollers.

3) In extreme cases someone may have tampered with the position of the whole guide roller assembly on either side. There is usually "China red" or black paint to shadow the proper factor jig setting.

The lift force on those arms is asinine and WAY over 1.5 oz. I measured it with a pull-down gauge and it pinned the gauge at 60oz and still didn't pull down.

After washing and relube, I always did a complete custom setup for the rollers and backstops. I was then able to weaken the lift springs and use approx 5 oz lift for the 100-104 and approx 10oz for the 200's I over-stretched one spring for a 3000 and brought it down to 5-6 oz and it still worked reliably.

These mach's were set on an assembly line using a jig and scribe to set the rollers and backstops. Problem is that the arms are pot metal and often slightly irregular, so instead of taking the time to do an individual calibration, they simply used a lot of force to make sure the records were lifted, no matter what. That is why some records got catapulted and smashed the little viewing glass on the 2700-2800 series.

I've described how to take apart and wash and realign these mechs several times here, if necessary, I'll go over it again.

The carousel was Wurlitzer's best mech and it was very reliable. Once properly set up, it should never have required any further adjustments of the robotics. Abuse and tampering change matters. The tone arm is mediocre.

Rob/NYC

Thanks. As I've discovered, there are a lot of interrelated adjustments. Hence my reluctance to fiddle with only those that I could easily access. Now that everything is out in the open, I can work more methodically through the things y'all have mentioned. The first time I worked on it, I didn't have a clue and, could have easily adjusted something that didn't need to be adjusted. I would have then adjusted five other things to compensate for the first unnecessary adjustment. Oh well, keeps me off the streets. So, I think I'll take advantage of the opportunity to recalibrate things properly. I'll search for other posts where you have gone over this (if you can point me to a specific thread, that'd be great). My biggest concern is making sure I attack adjustments in the proper sequence, i.e., get A properly adjusted, then onto B, C and so on, never returning to a previous adjustment. That was another thing I know I did initially. I would move back and forth between multiple adjustments to get things working properly.

Is there some special technique to stretching out the springs so that one doesn't take out an eye? I gotta believe mine are pulling well over 10 pounds.
Thanks
Brooks