Wurlitzer 1900 Centennial restoration

[viperz]

Well, I have been itching to restore another jukebox since I finished my Cadette, so I picked up Wurlitzer 1900 and 3010. I will start with 1900 first.

It needs quite a few cosmetic pieces (i.e. front pilasters and upper valance glass), but I'll start with functionality. 

It was given to me full of records with one record in the record player. When plugged in, that record is spinning, arm is not touching it, and it is not responding to cancel button - so I could only unload half the records so far. I assume I should be able to move the magazine motor by hand somehow (I already made sure no pins are selected in the selector)?
Speakers are humming quite loudly - amp has mismatched (but correct) tubes, mismatched fuses, but nothing is overheating or red-plating (I only plugged it in once).

I need to take it apart to move it downstairs into my workshop (and eventually it will just move to man-cave next door). I undid four transport screws on the mechanism. I can see an electrical connector going to coin mechanism, and two wires going to the amplifier (one to big round connector, one to phono connector), so I will disconnect those. 
The first question is - how do I lift the whole mechanism out without damaging it? There aren't many spots to really pick it up. How much does it weigh? And can it sit on the bottom (selector) metal box when removed?

Thank you.

I will start posting photos into this shared directory: photos.app.goo.gl/UXngD8cQSCaxMrWYA

[viperz]

OK, looks like I also need to disconnect front keyboard connectors from the changer mechanism... Also someone mentioned that the mechanism springs have to come out before the mechanism can slide out, unlike my Rowe where I lifted the whole mechanism with springs. Will try tomorrow morning while taking photos and labeling everything.

[Ron Rich]

Hi Eugen,
Check the position of the record load switch- if off, record will not be added/removed from the turntable--
Removing that mechanism is a two man job- it's too heavy/bulky to do by yourself, IMHO ! The springs need NOT be removed, but if not removed, they tend to "fly away", and hide in the darnedest spots-- Also note-- front and rear springs may not be the same !-- consult the partz book first ! Best to sit the mech shelf, on two "saw horses"--- Ron Rich

[viperz]

Uff, removed amplifier and coin register mechanism along with a bunch of other parts.

Completely disconnected the record changer, removed springs. Hopefully tomorrow I will get some help to remove it and move into my work shop area. I wonder if at that point the cabinet with 5 speakers and remaining stuff will be light enough for two people to take down the stairs. I may try to remove the front glass window, but I do not see how to disconnect the light harness from it.

[jukenorman]

I just place the removed Wurlitzer mechanism straight on to a dolly trolley, it means I can move it around easily. Then as I remove parts, it becomes lighter and easy to manhandle. Rebuild is the reverse - back on to the dolly trolley.
Norman.

[viperz]

We moved changer mechanism, amplifier and coin mechanism downstairs. The cabinet with front glass and 5 speakers is still very heavy.

I was looking for someone to write a generic restoration manual for Wurlitzers. I see that Ron wrote one for Seeburgs.

[viperz]

Would this be a good restoration reference manual for 1900 and 3010? www.alwaysjukin.com/items/jukebox-reference-books/wurlref2-detail.htm

I can restore all electronics based on the service manual, but I need someone or something to hold my hand with mechanical parts. My Rowe AMI was mostly self-explanatory, but Wurlitzers look to be more intimidating.

[Ron Rich]

Hi Eugen,
I have never "written" a "restoration manual" for anything !
As for Harold's writings, I have great respect for what he writes-- usually it is correct- However, I don't know what you are expecting-- ask the seller your question(s) ! Ron Rich

[viperz]

I finally got some motivation to work on this jukebox. Rebuilt the amplifier with all new electrolytic capacitors. Replaced one film capacitor on the board, and replaced blown R69-B resistor (looks like R69-A was replaced at the factory! - new resistor installed beside R69AB double resistor). Installed new 6L6 output tubes (amp came with mismatched 6L6GC and metal 6L6) and 5U4GB rectifier (original rectifier tests fine on my tube tester anyway).

Installed three jumpers on the connectors since the amp is on its own, and attached 8-Ohm speaker. So far, I got all DC voltages good (B+ and selenium rectifier both output good DC).

What is really concerning is that R68, R69A and R69B are getting so hot after 10 minutes that I cannot even touch them. They're power resistors - 5W (R68), and 15W (R69A and new R69B).

I tried injecting the signal into oscillator, but even at almost 2V, I could barely hear the output. I realize this is not the right way to do it, just wanted to try. I guess I can bypass the oscillator circuit by removing a couple of caps, and inject the signal straight into first voltage amplifier.

Just want to make sure first that everything works correctly, and figure out why resistors are getting so hot.

[jukenorman]

Hi Eugen,
Wurlitzer wouldn't have used a 15W resistor if a 10W resistor would have done! You've said the DC voltages are OK in which case the voltages and volt drops on the resistors should be to spec. - so it's just ohms law! 15W resistors invariably get hot, you just have to learn not to touch them!

Norman.

[viperz]

Hi Norman, I will go downstairs after work, measure voltages at all three resistors and calculate power consumption. Just want to make sure it is "normal". I had to install a 15-watt 9K resistor instead of blown 10-watt, because my calculation showed that at normal operation that resistor would experience 10-11 watt, so original resistor power rating was borderline at best. I only had space to install 15W metal power resistor rather than big ceramic tube, installed right on the chassis for good power dissipation, and my oh my it got hot.

[viperz]

So 250-Ohm R68, which is marked as 5 Watts on the parts list, gets about 6.4 Watts. It is definitely not a 5-watter installed there (big long ceramic resistor).

1650-Ohm R69A gets 5.5 Watts (big 15-watt resistor).

10K R69B (I replaced blown 9K) gets 9 watts. It is marked as 10-watt resistor on the parts list, and I replaced it with 15-watt.

Do they get hot or what...

[Ron Rich]

Hi Eugen,
Yes "cement block" resistors tend to run hot enough to remove human skin (don't axk !) !! Ron Rich

[viperz]

OK, I am finally getting to a point where I need someone to hold my hand.

For the mechanism assembly, or should I say disassembly, do I start from the top?

1) Remove the turntable mechanism (4 bolts and stabilizing shaft) to clean it, replace rubber isolators and clean the motor?

2) Remove selector coils portion from the bottom to clean all the fingers there?


I will also start taking apart coin register mechanism. I guess, I will remove the slug rejector to clean it, then check motor and coils around it?


Thank you

[viperz]

Ron, too late with the resistors warning, even though I spit on my finger before touching them... but my fingers are used to soldering iron burns