(Topic ID: 282913)

Gottlieb Rack A Ball not racking a ball!

By RetroRyan

3 years ago


Topic Heartbeat

Topic Stats

  • 17 posts
  • 5 Pinsiders participating
  • Latest reply 3 years ago by RetroRyan
  • No one calls this topic a favorite

You

Linked Games

No games have been linked to this topic.

    Topic Gallery

    View topic image gallery

    20201211_100726 (resized).jpg
    20201211_100726 (resized).jpg
    20201211_094958 (resized).jpg

    #1 3 years ago

    Hello all,

    I have a Gottlieb Rack-A-Ball I am resurrecting from the dead and its nearly there, except the rollover switches will not rack a ball. When any rollover switch on the game is engaged, the associated light goes out, a quick buzz is heard, and thats it. Switches look gapped correctly, no obvious wire issues, steppers have been cleaned, score reels are set and working correctly and all other features work. When I manually engage the lower left relay in the backbox a ball is racked.

    Any thoughts are appreciated. Thanks!

    Ryan

    #2 3 years ago

    On this game, a ball should be racked when a lit rollover it made. Unfortunately, I don't have a schematic for Rack-A-Ball, but I can make an educated guess that the circuit to energize the ball racking relay would be wired to a make-break switch on every rollover control relay. I believe that the rollover control relays are located in the long sequence bank mounted on the underside of the playfield.

    It may be that the wire for the ball racking relay has detached from its solder joint where it is supposed to be hooked in to the make-break switches on the sequence bank. If this has happened, it could cause the problem you are seeing. So, you may want to check for a detached wire along the solder lugs of the switches for the sequence bank.

    - TimMe

    #3 3 years ago
    Quoted from TimMe:

    On this game, a ball should be racked when a lit rollover it made. Unfortunately, I don't have a schematic for Rack-A-Ball, but I can make an educated guess that the circuit to energize the ball racking relay would be wired to a make-break switch on every rollover control relay. I believe that the rollover control relays are located in the long sequence bank mounted on the underside of the playfield.
    It may be that the wire for the ball racking relay has detached from its solder joint where it is supposed to be hooked in to the make-break switches on the sequence bank. If this has happened, it could cause the problem you are seeing. So, you may want to check for a detached wire along the solder lugs of the switches for the sequence bank.
    - TimMe

    Yes I have checked for a detached solder. No luck. What I need to know is what is the signal path from the rollover bank to the relay that racks a ball...With this information maybe I can jumper may way to the issue...

    #4 3 years ago

    Do you have a schematic? Can you post a snippet of the circuit the energizes the ball racking relay?

    Thanks - TimMe

    #5 3 years ago
    Quoted from TimMe:

    Do you have a schematic? Can you post a snippet of the circuit the energizes the ball racking relay?
    Thanks - TimMe

    I do not. Is there anyone out there with a schematic for Gottlieb Rack A Ball?

    1 week later
    #6 3 years ago

    Ok all I have a schematic!!! Here is a picture of the rollover section. Any ideas? Thanks!

    20201211_094958 (resized).jpg20201211_094958 (resized).jpg
    #7 3 years ago

    Here is the entire schematic for reference...

    #8 3 years ago
    20201211_100726 (resized).jpg20201211_100726 (resized).jpg
    #9 3 years ago

    This game has a series relay (the P relay) that is supposed to pull in with each rollover relay as that relay is tripped. An N.O. switch on the P relay, in turn, closes to actuate the G relay. It is the G relay that kicks a ball onto the rack and advances the rack count stepper.

    So, the next thing I would check would be the P relay to confirm that it is operating OK. I would also check that the N.O. switch on the P relay is closing properly and energizing the G relay.

    Note that the copyright holder for Gottlieb materials has told Pinside and other online sites not to post images of entire Gottlieb schematics. Please remove the large general images of the schematic in your posts #6 and #8.

    As far as I know, it's OK to post small snippets of schematic diagrams to illustrate a specific issue that you are having.

    - TimMe

    #10 3 years ago
    Quoted from TimMe:

    This game has a series relay (the P relay) that is supposed to pull in with each rollover relay as that relay is tripped. An N.O. switch on the P relay, in turn, closes to actuate the G relay. It is the G relay that kicks a ball onto the rack and advances the rack count stepper.
    So, the next thing I would check would be the P relay to confirm that it is operating OK. I would also check that the N.O. switch on the P relay is closing properly and energizing the G relay.
    Note that the copyright holder for Gottlieb materials has told Pinside and other online sites not to post images of entire Gottlieb schematics. Please remove the large general images of the schematic in your posts #6 and #8.
    As far as I know, it's OK to post small snippets of schematic diagrams to illustrate a specific issue that you are having.
    - TimMe

    TimMe Thanks for the info. I pulled the full schematic photo.

    So I tested the series relay and when I manually engage it racks a ball. So it sounds like P amd G relay are ok. Where do I check next? There's gotta be something off between P relay and rollovers correct?

    Thanks!

    #11 3 years ago

    OMG, looking at the schematic gives me bad flashbacks to the 5/50 RO scoring problem I had with Bowling Queen, and never did totally figure out.

    #12 3 years ago

    Does the P relay pull in when you manually activate a rollover switch? If not, then as you said, there's an electrical break somewhere between the common ends of those numbered relays and the side of the P relay that they're connected to. I guess the P relay coil could be bad also. You said you didn't see any obvious wiring issues?

    #13 3 years ago

    As paulace points out, if the P relay coil is dead shorted, then the rollover relays will still trip, but the P relay won't energize.

    To check for this, you can try the following test with any of the rollover relays. Hold one of the rollover relays in the latched (reset) position with your hand. While still holding the relay, use an insulated tool to actuate the rollover switch on the PF that energizes the relay you are holding. The relay you are holding should buzz loudly, and the P relay should also pull in and stay on the entire time you are holding the rollover relay in the latched position AND holding the PF rollover switch closed. As soon as you let the rollover relay drop, or release the PF switch, both the rollover relay the P relay should de-energize.

    If you can energize the P relay doing the above test, then I suspect the make-break switches on your rollover relays are adjusted to open very early as each relay trips. That would break the connection to the P relay so quickly that the P relay would not pulse long enough to energize the G relay. If that is the case, try adjusting the make-break switches on the rollover relays to open later, to see if that gets things working again.

    If you can't energize the P relay by doing the above test, then the next thing is to determine why the P relay never pulls in. It could be a dead-shorted P relay coil, or there could be a wiring short between the rollover relay coil common wire and the transformer black wire. Such a short could either happen by accident, or because of a prior incorrect repair attempt on this part of the circuit.

    One thing to remember is, if you can actuate a rollover switch on the playfield, and that does indeed trip the corresponding rollover relay, then in theory the P relay coil MUST be getting energized unless it is somehow shorted out or bypassed. That's because the P relay coil is part of the common return wiring for all of the rollover relay coils. (If this part of the circuit were open, then none of the rollover relays could trip.) This is why the P relay is called a series relay - it is wired in series with the rollover relays.

    This also means, of course, that the P relay coil and all the rollover relays need to be 12-volt coils, rather than the usual 24-volt coils. So, it would probably be a good idea to check the P relay coil and confirm it is an R20-2 coil.

    - TimMe

    #14 3 years ago

    Is the original R20-2 coil in use in the series relay?

    #15 3 years ago

    Ah, my logic was faulty - as TimMe said, if there were a break between the commons of the rollover relays and the P relay, none of the rollover relays would activate. Sorry about that.

    I learn so much reading these threads - thanks @TimMe!

    #16 3 years ago
    Quoted from paulace:

    I learn so much reading these threads - thanks TimMe!

    No problem!

    And thanks to pinballdaveh for the suggestion to check for an R20-2 relay coil. I thought of it several minutes after posting and updated my post, but I think he got there first.

    1 week later
    #17 3 years ago
    Quoted from TimMe:

    As paulace points out, if the P relay coil is dead shorted, then the rollover relays will still trip, but the P relay won't energize.
    To check for this, you can try the following test with any of the rollover relays. Hold one of the rollover relays in the latched (reset) position with your hand. While still holding the relay, use an insulated tool to actuate the rollover switch on the PF that energizes the relay you are holding. The relay you are holding should buzz loudly, and the P relay should also pull in and stay on the entire time you are holding the rollover relay in the latched position AND holding the PF rollover switch closed. As soon as you let the rollover relay drop, or release the PF switch, both the rollover relay the P relay should de-energize.
    If you can energize the P relay doing the above test, then I suspect the make-break switches on your rollover relays are adjusted to open very early as each relay trips. That would break the connection to the P relay so quickly that the P relay would not pulse long enough to energize the G relay. If that is the case, try adjusting the make-break switches on the rollover relays to open later, to see if that gets things working again.
    If you can't energize the P relay by doing the above test, then the next thing is to determine why the P relay never pulls in. It could be a dead-shorted P relay coil, or there could be a wiring short between the rollover relay coil common wire and the transformer black wire. Such a short could either happen by accident, or because of a prior incorrect repair attempt on this part of the circuit.
    One thing to remember is, if you can actuate a rollover switch on the playfield, and that does indeed trip the corresponding rollover relay, then in theory the P relay coil MUST be getting energized unless it is somehow shorted out or bypassed. That's because the P relay coil is part of the common return wiring for all of the rollover relay coils. (If this part of the circuit were open, then none of the rollover relays could trip.) This is why the P relay is called a series relay - it is wired in series with the rollover relays.
    This also means, of course, that the P relay coil and all the rollover relays need to be 12-volt coils, rather than the usual 24-volt coils. So, it would probably be a good idea to check the P relay coil and confirm it is an R20-2 coil.
    - TimMe

    TimMe, you are the man! I ran the test above and P relay tested ok and energized. I went through and adjusted make break switches as you suggested and rollovers began to come to life. After an hour of going through every rollover gap and make break gap on the relays everything works! Crazy to me that so many switches could be out of whack but hey, I guess it can happen after all.

    Now to my last problem.....the 50 point targets aren't scoring. Any thoughts on this?

    Thanks guys!!

    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/gottlieb-rack-a-ball-not-racking-a-ball?hl=paulace 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.