(Topic ID: 140462)

1949 United Mfg "Utah" pinball - loud buzzing

By PinballFever

8 years ago


Topic Heartbeat

Topic Stats

You

Linked Games

No games have been linked to this topic.

    Topic Gallery

    View topic image gallery

    20151002_195146.jpg
    20151002_211302.jpg
    Score_Motor_Switch_Adjustment.png
    458632.jpg

    #1 8 years ago

    More information about the game here. https://pinside.com/pinball/forum/topic/40s-united-pinball-machine-cleaning-question

    There is no schematic for this game so I'm asking your help with troubleshooting this issue here.

    -------------------------------------------------------------------------------------------------------------------------------

    The game used to complete the reset sequence but now it stops with the 900,000 and 90,000 lights lit.

    The 10,000 Step Up Unit is staying energized causing the loud buzzing but I'm not sure what's keeping it energized? What should I look for?

    Thanks in advance,
    Bruce

    458632.jpg458632.jpg

    #2 8 years ago

    Stuck closed switch on the playfield.

    #3 8 years ago
    Quoted from KenLayton:

    Stuck closed switch on the playfield.

    That was my thinking too.

    It started after I removed the 10 passive bumpers for cleaning and new rubbers then put them back in.

    Will check them for closed switch after work today.

    Thanks,
    Bruce

    #4 8 years ago

    On my Singapore, occasionally I'd push in the slide for a reset and the 10,000 point stepper would buzz real loud as if something in the reset wasn't completing. It would buzz until I killed the power. I'd power the game up and it would be alright until I tried to reset again. Intermittently.
    That's the primary reason I took the time to reverse-engineer the schematic and process sequences. If I don't know how it is supposed to work then it can be more difficult to diagnose problems.

    In my case, the home position switch on the score motor wasn't adjusted correctly. There are a few switches on the home position switch stack, one controls where the motor stops. This is a note I made on my diagrams:
    Score Motor Switch Adjustment.pngScore Motor Switch Adjustment.png

    If that helps any.

    #5 8 years ago

    The diagram I posted should say "B to change state before A opens"
    In my case, "B" controlled the 10,000 point solenoid that was buzzing. "A" controlled the score motor.

    The problem would happen when switch A opened first that caused the score motor to stop turning. Sometimes there wouldn't be enough drift in the cam and switch B wouldn't change state, causing the solenoid to stay on and buzz.

    #6 8 years ago

    Steve,

    Thanks for the tip. Someday soon I'd like to buy the schematic that you made for your game.

    ==============================================================

    It's FIXED and is what I thought it would be. Ken was correct. The new rubbers were tighter pushing in one or two passive bumper switches.

    I had to use the Harbor Freight head magnifying glasses with lights to be able to see them well enough with my aging eyes so I could gap them correctly with the switch adjuster.

    Thanks guys,
    Bruce

    Harbor Freight head magnifying glasses with lights
    20151002_211302.jpg20151002_211302.jpg

    Passive bumper switch
    20151002_195146.jpg20151002_195146.jpg

    #7 8 years ago

    Here's a shameless plug:
    You might be interested in this thread:
    https://pinside.com/pinball/forum/topic/for-sale-1947-united-singapore-pinball-schematic-and-diagrams

    I am sure some circuits will be different but there are probably many similarities.

    #8 8 years ago

    Steve, is that smaller/larger gap design a quirk of this era or do you know if that is present on newer machines? That would be a killer to diagnose if you weren't aware of it!

    #9 8 years ago

    Thanks Steve. I plan to order one soon but would like a printed paper copy similiar to a real schematic if possible?

    I marked the topic as Solved.

    Bruce

    #10 8 years ago

    Dr_nybble:
    I am not sure about the other games.
    PinballFever:
    You can always take the file to a Walmart (etc) and make a hard copy for yourself.

    #11 8 years ago
    Quoted from SteveFury:

    You can always take the file to a Walmart (etc) and make a hard copy for yourself.

    I'll paypal you for the schematic when I get the next paycheck.

    Bruce

    Reply

    Wanna join the discussion? Please sign in to reply to this topic.

    Hey there! Welcome to Pinside!

    Donate to Pinside

    Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!


    This page was printed from https://pinside.com/pinball/forum/topic/1949-united-mfg-utah-pinball-loud-buzzing and we tried optimising it for printing. Some page elements may have been deliberately hidden.

    Scan the QR code on the left to jump to the URL this document was printed from.