Gottlieb Solved Big Brave (Gottlieb, 1974) "O" relay not releasing

njPinWiz

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Machine turns on fine, credit button sets of relay sequence. "O" relay pulls in but doesn't release. Ball in drain hole does not kick out because "O" coil not being energized. Anyone have any suggestions?
 
Solution
Also called an 'interlock' relay. Shown as 'reset completed' relay with coils shown V- , VR. The operation manual mentions Start relay actuates VB releasing the armature on "V" relay(I think that means VR so anything to make this even more FUBAR. The VR coil circuit also goes through a set of 2b contacts and on to the 'Zero' contacts on ball counter. You never mentioned the position of your ball count unit or if it is resetting all the way to zero. It most likely is as the next part of VR circuit flows through ,in series, every motor run-out switch on score reels. When in V ,or call it V-, position contacts on the V part activate relay Z coil. Z is the 'Reset relay' Those V contacts are the only switch that powers the Z relay coil. I...
A little rusty here. But , I think the ball hits a trough switch, after ejecting from outhole, that advances the ball counter to ball one position. That starts the game. I don't think the score motor pulses the outhole coil. Is power going to the outhole eject coil? And coil test Ok? A 1972 Gottlieb 'Grand Slam' schemo is as close as I can get to your game. I will take a look to try to see how that coil gets triggered.
 
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Coil, the basic problem is that when game starts up after pressing credit button, the ball remains in the out-hole. In looking at schematic, the 4c motor switch should be pulsing the "O" coil to trigger the kick-out mechanism to pass the ball over the through switch. I tested the "O" coil and it does receive power (only if I physically close the 4c switch to energize it), so that coil is good.
 
It sounds like the circuit is good and the relay, score motor contacts are working. If those contacts are adjusted & work it might be a set of score motor contacts that run the motor until the outhole kicks the ball to the shooter. They could be on a relay or the score motor. It seems like the score motor should run until the ball leaves the outhole. That is the last thing that happens during the game reset & start. Is the game over light staying on ?
 
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It's not getting to game over, so don't know about the light coming on for that. Right now the ball stays in the out-hole. The motor turns about 6 times while game resets. Drop targets reset properly, the reset bank energizes and resets all the relays (SB1, SB2, QB, etc.) on the reset bank. But, O coil to launch ball to plunger doesn't fire. I can trigger it manually by forcing 4c switch on score motor to make contact.
 
Is the problem right there with 4c contact ? Why is it not making contact while the motor turns ? It looks like only two contacts that fire 'ball return' coil, n/o 4c & n/o contacts on 'o' relay. That circuit is always energized. As long as 'o' relay remains puled in, 4c should fire ball return coil. Is 4c mis-adjusted? Maybe the 'o' relay is opening at the wrong time during score motor rotation ? If n/c motor contacts 2b open at the wrong time , 'o' relay will not be pulled in when n/o 4c closes. Same goes for 'v' contacts on reset completed latch/trip relay. About that 'game over' light. It is on while ball count unit is at '#6'(game over) position. Is your ball counter snapping back to 'zero' position during reset?
P>S> I just re-read your top post saying 'o' relay fails to pull in. I though it was working. Is this still part of the problem? 'Latching 'v'contact on 'v,-v' relay' thru 2b thru outhole switch , activate 'o' coil. Those n/c contacts plus n/c motor 1c must (also)be closed when the ball ejects from outhole then hits the trough switch. Closing trough sw thru 1c thru 'v' thru 2b then energizes the 'add ball' coil. That moves ball counter from 'zero' position, up one notch, to ball 1 position... That Starts The Game :dance:
 
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The 4c is making contact several times as the score motor revolves during game reset. But, it seems like maybe the timing is a little off...what I mean is the 4c switch makes contact/closes & then opens repeatedly but it seems to need the "O" relay to be pulled in before the "O" coil is energized/ball return activates. On game reset it seems like the motor stops turning and then the "O" relay pulls in.
 
Just finished editing above. Check out my circuit descriptions...I have had those timing issues. It is usually N/c contacts open at the wrong time(while motor runs). It is important to note>Pinball schematics always show the condition of the game while it is on AND the game has reset AND is ready to play w/ball #1 at the shooter. So some relay contacts shown normally closed may be open if power is removed and some n/o contacts will be closed with power off.
 
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Update: Tested by jumping back side of 10amp fuse to ball return (coil fires); XB relay to ball return (coil fires); score motor 4c relay to ball return (coil fires); p relay to ball return (coil fires) and O relay to ball return (coil fires). All seem to work fine independently, but the entire circuit when ball is in out-hole and game is started by pressing credit button doesn't....??? Am perplexed.
 
O relay must be releasing at the wrong time preventing 4b from reaching the coil. Try checking the operation of score motor 2b contacts, possibly jumping them closed(risky ?) while starting a game. Those and 'v' contacts also need to be closed, together they hold the o relay closed when 4b tries to fire the outhole coil.(? , That's from memory) I'm gona try a thing or two with that 'Grand Slam' game-o-mine. Other than scoring, I think the main operations are similar. Maybe I can get a hint ...
 
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Thanks Coil, one question - what is the 'v' that you are referring to?
 
I believe the V, -V contacts are on one of those 'latch/ trip' relays. At least I think that is the correct term. Ax/Bx comes to mind too[not in this machine?]. V must be while the thing is latched and -V must be when the relay has been tripped (reset). Those things don't move a whole lot. The contacts are harder to get just right. These relays replace those reset banks 'cuz they got too expensive and nobody liked them either. They do remember their state, like memory, even without power. You must be homing in on this fault. I'll pull out the schemo and see if there is anything to add ....
P>S> Maybe I will add, I am not exactly a wiz at this.
latchre2.jpg


Maybe this is a ax/bx widget >
gtbaxrelay1.jpg

These are the adjustment A-Holes....
 
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Also called an 'interlock' relay. Shown as 'reset completed' relay with coils shown V- , VR. The operation manual mentions Start relay actuates VB releasing the armature on "V" relay(I think that means VR so anything to make this even more FUBAR. The VR coil circuit also goes through a set of 2b contacts and on to the 'Zero' contacts on ball counter. You never mentioned the position of your ball count unit or if it is resetting all the way to zero. It most likely is as the next part of VR circuit flows through ,in series, every motor run-out switch on score reels. When in V ,or call it V-, position contacts on the V part activate relay Z coil. Z is the 'Reset relay' Those V contacts are the only switch that powers the Z relay coil. I think the V contacts circuit are 'splained above.[Is this helping 'cuz my head feels kinda funny "Right About Now, Funk Soul Brotha"} ... after a short "refreshment". The operation manual seems at odds with the schemo. I'm trying t figure the start up sequence.Fail. Back to that 'O' relay ...It is said to have contacts that run the score motor. Like there is a strong likelyhood that the score motor should be running whilst the outhole is occupied. You have mentioned the 'O' relay seems to wait for the score motor to halt, then closes. That just will not do . Lets all look for those alleged contacts, shall we? Well YES, there is a set of 'O' contacts that can run the sore motor. What is the Catch22 here? Again, that 'O' relay coil sure has plenty pathways to that could turn it on OR off.
At this point ... I think a really good test is to isolate and bypass(short) the proper score motor 4c contacts. The actual outhole coil circuit is shown damn simple, right?. Coil>>>1 'o' relay contact>>> 4c. That's all Folks...Try a reset with 4c clip leaded closed. If the ball stays in the outhole it points to the tangle of O contact's, a broken connection or bad timing of some other circuit. Should it leave the nest , the timing of 4c operation has to be the hitch in your get-a-long.
 
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Solution
PROBLEM RESOLVED!! A big thanks to the Pinball Nirvana community for all your suggestions. It was indeed the "O" and "P" relays that were the source of the problem. It took quite a bit of finesse setting of the switches in each of those relays to finally get it tuned correctly. Just finished up playing a bunch of games to test the game & it's now working 100%. Appreciate everyone's comments. Your suggestions & comments helped me tremendously in better understanding Gottlieb EMs and the tricky nature of each & every switch!
 
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