new to me 3700 attempting to bring it back to life

[sh0rtlife]

now on with the show
so ive been printing off and blowing up the wiring diagrams from the manual from the past couple weeks and to make things easier using fine line sharpies to color code wires i wanted to chase..specificaly off the ry-1 relay as ive known its a "weak" state voltage, the fact that i bumped and found an unrelated reed switch that brought it all to full function is beyond me as its not wired to the relay in ANY WAY... it ran back thru the timing board

so i want to leave this here encase anyone runs into an odd issue of which is probably true all the way down to the 3400? maybe further

triacs! probably toast

keyboard ground!, each key switch has3 or more contact plates but each plate is 2 fingers, if any 1 finger is broken things may not work. go thru with a magnifying glass or soldiering goggles and check ALL of them, in my case i replaced more than half on the keyboard and simply replaced the number board..to do this youll need 2.33mmx3mm tall, youll also need a donor board from any machine that uses the same keyboard slides3400-3800 confirmed to be the same, drilling the old rivits its delicate work, DO NOT toss the bad ones, as in many cases they are a stacked U shape in some slots youll need half of one..so cut and re-use where you can, youll also need "Beadsmith EZ Rivet Piercing & Flaring Kit - includes 3/32" T-bar screws" to re-rivet them in...i recommend superglue to "set" the rivets before pressing or its a NIGHTMARE to keep them in place....any one bad ground will cause anything from chattering solenoid to non functional they all run in a series

BO/AC bypass!! 2 and 6 are all thats needed on the basic machines(they do not have 7/8 populated), the "fancy"(3710 3760 for example) machines need 7/8 for the extra fancy stuff to work, but still only need 2/6 for basic function

most voltage cant be straight tested on these ole rigs and a test light is the ONLY way..found this out trying to chase low voltage back to the transformer...broke out the light and found full voltage

relays, "yellow socket" is 12v "white socket" is 24v, if a machine wont credit it may have a 24v relay in the 12v socket

[sh0rtlife]

so heres where i stand

the grabber arm "thumb" will sometimes "walk" its way out and crash a record..not sure the how or why of this and its 100% random....by the time the switch to stop it triggers its too late..sometimes it will walk out while sitting idle more often tho it walks out while the carousel is in motion

1-0 lights are still wonky flashing only 5-0 if you look close but from normal distance it looks like just 6 and 0...bulbs are new..so im at a loss

grab arm wont always "seat" where it should, more often than not its on the stop screw at the needle but up on one side..doesnt seem to matter which record side is played for it to happen...sometimes it fails to sit all the way down on the stop screw

the newest issue is the turn table not always being pulled over into the motor fully, which i suspect is due to replacing the motor mounts? and genuinely needs adjusted?

im hesitant to start making adjustments but i very well may be at that point..ive read soooo many posts in here about adjusting and just making things worse i dont want to put myself in that spot!!!!

[jukeboxmarty]

Jul 24, 2024 17:49:17 GMT sh0rtlife said:

im not mad or pissy..im thankfull for the help ive gotten, even to the odd links that have helped me find "bonus" issues that i didnt even know were an issue..that leepfrogged me into a better spot to sort it out

Actually, we are glad to know that people are benefiting from the forum.

I just ask that you word things in a way that doesn't discourage others from helping you.

I know he can speak for himself, but Norman has been good to work with you on this thread, and even provided a manual you didn't have. From my perspective, one of your posts sounded like you were trying to set him straight! Maybe not your intention, but you don't want to scare the experts off!

[jukenorman]

I'm not really sure where we go with this! I've tried to help you out to the best of my ability but as I stated right at the beginning of this thread, I never work on 3700's other than the occasional 1050. The 1050 is a 3700 in a retro cabinet - if you buy a 1050 manual from a reputable seller, what you get is a 3700 manual plus a 1050 supplement. 1050's are fairly rare and it's probably about ten years since I last fixed one so not exactly fresh in my mind! There are likely 100 or more other jukeboxes with which I am more familiar.

You seem to have done a "data dump" of problem above, and in your own words without any reference to the manual. I have to say that I'm still struggling to properly understand your issues and I simply don't have the free time to sit down with the manual searching for the sections that might pertain to these issues. Otherwise I will help if I can, that's the best that I can offer!


Norman.

[sh0rtlife]

Jul 25, 2024 11:54:34 GMT jukenorman said:

I'm not really sure where we go with this! I've tried to help you out to the best of my ability but as I stated right at the beginning of this thread, I never work on 3700's other than the occasional 1050. The 1050 is a 3700 in a retro cabinet - if you buy a 1050 manual from a reputable seller, what you get is a 3700 manual plus a 1050 supplement. 1050's are fairly rare and it's probably about ten years since I last fixed one so not exactly fresh in my mind! There are likely 100 or more other jukeboxes with which I am more familiar.

You seem to have done a "data dump" of problem above, and in your own words without any reference to the manual. I have to say that I'm still struggling to properly understand your issues and I simply don't have the free time to sit down with the manual searching for the sections that might pertain to these issues. Otherwise I will help if I can, that's the best that I can offer!


Norman.

greatly appreciate the help thus far

ill try and pull some direct reference from the manual i have and see if that helps explain things better

FWIW i managed to get it to play a few records last night as i picked up 14 for 7$ to use for testing..dont want it breaking one thats been with me since the begining!!!!

...aside from the 1.2.3.4.5.6.7.8.9.0 display still flashing 6/0 back n forth it pretty well had only an issue of the arm setting the record down, releasing it but not setting the arm fully down so the needle would collide or scrape across it..a lil nudge of the arm on the high side and it would be fine.. ran about 6 and it cleared fine on 2 out of 6

[sh0rtlife]

i printed off the 3500 manual just so i could be as clear as possible..and well im old school i prefer digging thru a manual more than viewing it digitally


partially fixed my record number display, it seems 1 bulb wasn't seated right but now the issue changed 2, 4, 6, 8, 0 all work as intended..the "odd" ones dont, which leads me to believe its well the main lead on that side, problem is both the 3500 schematic and the 3700 schematic show a different amount of wires and both of them show said wires going to a contact switch and dont even list a wire color/number....so i feel like im miss reading something in the manuals...but maybe this is a 200 play vs say a 100 play kind of thing?....what i know is 1/2, 3/4, 5/6, 7/8, 9/0 each have a wire with a pair of diodes(i think) splitting even/odd, and then the other side of each bulb is wired in even/odd pairs(2 separate shared grounds?)..regardless..manually chased the wires and lost them at the plug into the accumulator selector plug


record takeout arm issue
so it picks up the records fine, sets them down fine but isnt always "seating" on the record takeout arm stop adjustment screw, it "usually" does but even then its still 2degrees or so mid rotation.. in the center point of the arm between the carousel and the adjustment screw would be up anything from 1/8th to 1/2 inch and its random....thus im hesitant to really go adjusting it..sometimes it will sit on the adjusting screw and sit level as intended..but thats about a 2 in 10 chance

i "think" the home position of the takeout arm and the "record clamp" sliding out for no reason seems to have stopped...but i still dont trust it with my good records yet..doesnt seem to be any reference in the manual about it even

i dug thru the troubleshooting in both manuals and found no reference to the takeout arm


what do you guys think, should i start doing adjustments?...everything here on the site says DONT so im real hesitant....but i think i may have reached that point...and lets face it i picked it up at a car wrecking yard...hell i personally didnt transport it correctly as i didnt know better..so who knows how much this ole girls been bounced and knocked around..never mind the 75000+ plays on it

[sh0rtlife]

maybe this will help, i took some shots of how the takeout arm is behaving






i dug thru thru both manuals looking at adjustments and NOTHING references this issue specifically, theres a few that referance adjusting the stop point but if theres something about getting full travel i must have missed it, however....with that said i belive i found the issue...im just not sure if there is a way to adjust and compensate for it

below is a couple shots of the gear that has a slot in it that then cams out and drives the takeout arm, theres a rather deep groove in it thats Sharpe edged and obviously wear, im open for ideas here....if the drive gear for the takeout arm assy was set screw locked and not roll pinned in place i suspect i could rotate it slightly and solve the issue
basically i need to compensate for a lack of total gear travel that is keeping the takeout arm from hitting the stop point consistently

[jukenorman]

Something doesn't look right there - the support bracket looks too high? Have you got a parts listing in your manual? Although that bracket isn't particularly clear in the parts list, you might be able to compare it? It's item 40 on page 38C.

Norman.

[sh0rtlife]

Jul 27, 2024 10:00:24 GMT jukenorman said:

Something doesn't look right there - the support bracket looks too high? Have you got a parts listing in your manual? Although that bracket isn't particularly clear in the parts list, you might be able to compare it? It's item 40 on page 38C.

Norman.

yeah thats the illusion it gives, but in fact the takeout arm in those pictures is not touching it..take a closer look at the pictures, its about 1/2 inch above it, if i press it down into place the tone arm clears  it and plays without issue, i checked the measurements on that and its in spec..like i said "sometimes" it will fully put itself flat on the support as it should but im starting to think its only on the "heavy thick" 45's giving it the extra weight to help it finish out the rotation

it seems to keep coming back to an "unfinished" rotation of the takeout arm, that i "think" is caused by the wear in the cam assembly not fully caming out roller bracket and thus not fully turning segment gear which turns the entire takeout arm assembly, which would explain why its not side a or side b issue and totaly random..take a look at the wear in the second set of pictures

this is my first juke so i may be totaly out in left field

if you want/need pictures or..video of anything let me know and ill shoot it

[sh0rtlife]

going thru the manual more, and manually running the motor assy

page 28c of the 3500 manual

powered off!!

im manually rotating the motor assy #33, which drives the whole assy
i can visually see and watch that the roller on part #11(roller bracket assy) has worn away and made a groove in #16(cam assy), if i keep rotating the motor by hand till the take out arm has pulled a record, placed a record, stops, and begins to pull the turn table in to the motor the takeout arm is still hanging in air(this is just at the point where it would swing the tone arm out)

a note of the roller on #11 its sitting in a deep wear groove, if i use a small screwdriver to gently push it up off the cam assy, the takeout arm plops down onto the stop adjuster as it should

so at the very least i think i know where the issue is....

if you take a close look at #9(Actuating A r m and Huh Assembly) there looks to be an adjuster on it..
in the machine there IS an adjuster on it! and its painted pink?
however neither manual i have 3500 or the crappy 3700 i got online even make a reference to it, it appears to adjust the spring tension on the cam roller but i cant be 100%...

all i can be sure of is after multiple manually rotating the motor, lifting the roller off the cam slightly, puts the takeout arm firmly on the stop

[jukenorman]

Your machine looks to be generally lacking lubrication. I know that won't help a groove that has been worn - but it might have helped prevent it in the first place, not that this was down to you! Check your messages.

Norman.

[sh0rtlife]

checked and MUCH thanks

before asking any questions on here the first thing i did was troll thru about lube and oil, and picked up oil and started by cleaning/oiling everything i could reach, i did NOT oil/lube gear faces as i couldnt find anything that was generaly agreed on for gear faces, there are only a few spots un-oiled as i need a seriously long needle point to get to them

this machine CLEARLY lived in a HEAVY smoke enviroment and does not take good photo's...it also doesnt clean well on the insides

i played with cycling a bit more lastnight
3700 manual page 36C
parts 2, 3, 4, 5, 6 the the assembly that controls the takeout arm from the motor side of things..or atleast this is what gets it from the carousel to the table

looking at #3 in the book it looks like there is an adjuster...this is the pink painted adjuster in my machine that i "think" is designed to adjust
"5. Segment Gear, Record T r a n s f e r"
but maybe this was a factory adjustment that was never ment to be used again?

i do know that the roller on #6 is trashed..it rolls but its loose, and somewhere in its life when that roller was failing it cut a grove in the cam gear(#11)

what i think is that the "unlisted" adjuster is for adjusting the gear against the roller which would change how the spring tension rides the roller in the cam gear

idealy one would replace both parts, but realistically i may not find those parts aside from buying a whole machine

against my better judgement i did try adjusting the coupler...3700 manual, page 43C, part #19..or..in reality the OTHER part #19 that goes on the other side of part 18, i did this in an attempt to get more rotational roll out of the takout arm, the problem i had every time was that the spring , gear, cam assy from page 36 just rolls it bit and take up the slack leaving the arm in the same spot, no amount of adjusting on coupler could get me flat on the table...seemed like a good idea, i managed to exagerate the issue but i couldnt actualy make it better, so i re-aligned it




back on the "no play" issue that is SOLVED
im going to have to post a picture for you guys..as it may help someone else with a 3700/3800
there is a contact set, NOT LISTED in the adjustments, NOT in the pictures either, and NOT shown in the schematic
under
LETTER AND NUMBER LATCH SWITCH ADJUSTMENT
page 5B of the 3700 manual...take a look at the picture and you will note 2 black dots to the upper left.....on my machine there is a switch mounted to the 2 those 2 holes...EVERYTHING credit related goes thru this switch...the roller where it says "latch switch" on the mounting plate keeps said contacts connected and releases the credit once selected
so if someone comes along who cant get a machine to play..have them check it!!!!!!!!...i found it by mistake

[sh0rtlife]

first 2 pics..note that pink wired set of contacts...this was the "no credit" no play issue...just this unlisted contact set..and YES its still out of adjustment as im currently using it as a free play trigger..and will likely wire a switch from it to the coin return button as a free play trigger

since im playing with the takeout arm, and the tone arm likes to crash it..i cut a small chunk of fuel line and slipped it over the tone arm shaft to prop it up...GREAT service tool to keep it out of the way while chasing issues without hurting anything or fowling any switches

73187 plays..is pretty impressive..and explains the wear!!!

its such  a pretty machine...if i can just find a fix for the takeout arm travel..yeah light gap at the bottom...right side of the bottom speaker door has crumbled and the latch has fallen off..i plan to replace it once fully functional, also the door alignment pins for the speaker access door were missing and ive no referance of what they even looked like

[sh0rtlife]

well being stuck, i figured out a MUCH better free-play method that doesnt keep the latch solenoid energized, and ran 2 wires off the switch down to the coin switches..any coin triggers a the latch ..its not exactly freeplay but the wires from that mystery switch could be ran to a switch off the coin return button as well for freeplay...overall i feel its better on the parts doing it this way

picked up a exceptionaly clean 10000 plays 3700 with ALL the extras as it has the 2 selection play 10s even came with the remote mute/volume control, seems to have a couple blown caps but is like i said in AMAZING shape except 2 chunks missing out of its blue side plates where the doors spring rods crashed it...for 100$ i feel like i scored..was full of records too with 6 or so that are"for dj use only" , "do not resell"'s and such..so kinda rare, and a good 20 records of stuff me or my wife would have paid for

for now im going to slide the new 3700's whole play table assy into place in my cabinet while i work on the old one on the bench
FWIW i "think" i found a solution for the roller and cam but the whole transmission has to be disassembled

in the end i WILL end up with 2 complete working machines...but with the plastic damage on the one it will likely have to be painted..however the chrome and blue metal inlays sparkle and look amazing..wife will have hers ill have mine, one on the 1st floor one on the second..all will be good LOL

[sh0rtlife]

oh right..if anyones curious about the selection display numbers 1-0 only lighting up even numbers and not odd, i chased the wires and it seems its working as intended, it wont switch from even to odd untill the takeout arm triggers the side A/B switch at that point the switch changes the ground for the lights from evens to odds