Granny and gators pinball problem - UPDATE **FIXED**

Birdman661

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Granny and gators pinball problem - UPDATE **FIXED**

My granny and the gators is having issues. The video part of game plays fine but when you are supposed to play pinball, nothing happens. The ball won't eject onto play field. The flippers work and the pinball game will score points if I roll the ball thru gates and such, but the ball won't pop up so you can start the pinball game.
In self test, none of the solenoid a fire. I can hear the relay click in the appropriate spot per the manual, but none of the solenoid a will fire. Since it's all of them, I'm guessing it's a solenoid driver board issue but I really have no clue.
Any help or direction would be greatly appreciated.
 
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Look for the common power wire on each coil and make sure a wire hasen't broken off one of them....Pull the fuses to test them to make sure they are good....
 
I just tested the ones on floor of cabinet. I will look for the ones on bottom of play field.
 
Ok I found a blown fuse on bottom of play field and replaced it.

When I turned game back on there's a loud hum like the solenoids are trying to fire..but they don't- then fuse blows again.
 
Sounds like a big issue - you should sell the game to me and save yourself the trouble.

All kidding aside - these issues are annoying. Meter the coils as stated above looking for a short. Also - if that doesn't show the issue - consider unplugging driver board and or power board connectors and seeing if fuse still blows... Then add a connector/component one by one (I do with game off). That may help nail down what's blowing the fuse.

You can use a small circuit breaker with alligator clips rated the same as the fuse to save fuse costs.
 
Ok I found a blown fuse on bottom of play field and replaced it.

When I turned game back on there's a loud hum like the solenoids are trying to fire..but they don't- then fuse blows again.

Sounds to me like you have a shorted transistor which caused one of your coils to burn up. Test the transistors on the lamp/solenoid board for ones that are shorted out. Tip 102's are an equivalent replacement. If you find a bad transistor, check the corresponding coil as well.
 
Ok I metered the coils. All tested above 3 ohms which based on what I've read seems to be ok.
I've figured out When the machine is powered on the loud hum comes from the solenoid pictured. It fires but never released and stays engaged until the fuse blows. It's the one on top left of play field. Some sort of ball eject hole.

Sorry for the lack of correct terminology but this is my first real experience with pinball.

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look in the manual for the associated transistor for that coil. in baby pac those kickouts are called saucers IIRC.
 
You have a bad driver transistor


I concur with drewscruis that it is probably a bad driver transistor however I would also note that there is a possibility that the switch on the saucer itself is physically stuck closed which would cause it to energize immediately as well. My Baby Pac had this problem after I removed the playfield to restore the cabinet. I didn't realize that the saucer kick-outs were active when the game was turned on (thought they were only active when game went into pinball mode) but as it turns out the saucer coils were active and my problem was a stuck closed switch. Physically fixing the switch resolved my issue.

So you have two things to troubleshoot. Take a look at the transistor on your driver board to see if it measures differently than the others and also take a look to see if the playfield switch is stuck closed.
 
The area with the stuck solenoid is called the top saucer according to manual.

I can find "top saucer" in 2 spots on the schematics...however I have no idea what any of the symbols and squiggly lines mean so I can't figure out which transistor goes to the top saucer.
Anyone who can read a schematic care to point me to the correct one.

Also to test that transistor do I need to de solder it from the board?

Thanks and this should be a link to schematic

http://mirror2.ipdb.org/files/1083/Bally_1984_Granny_and_the_Gators_Schematics_paginated.pdf
 
The area with the stuck solenoid is called the top saucer according to manual.

I can find "top saucer" in 2 spots on the schematics...however I have no idea what any of the symbols and squiggly lines mean so I can't figure out which transistor goes to the top saucer.
Anyone who can read a schematic care to point me to the correct one.

Also to test that transistor do I need to de solder it from the board?

Thanks and this should be a link to schematic

http://mirror2.ipdb.org/files/1083/Bally_1984_Granny_and_the_Gators_Schematics_paginated.pdf



Looks like it might be Q34??? I would check that against others near it - if all others read similar you'll know one way or the other. I don't know when you have to remove from board to test because I've heard recommendations both ways. I can say I've identified bad transistors by comparing measurements when still soldered in the board... doesn't make it best practice though. (To avoid confusion - game is off!)

Also check for your switch being stuck closed like I mentioned earlier. That takes 2 seconds. I'd definitely check that before de-soldering anything.
 
Just to update this- I replaced the transistor at Q34 with a new one and the game now plays correctly and all solenoids pass the self test and fire in sequence.

A HUGE THANK YOU to all of you that chipped in and helped on this.
 
Just to update this- I replaced the transistor at Q34 with a new one and the game now plays correctly and all solenoids pass the self test and fire in sequence.

A HUGE THANK YOU to all of you that chipped in and helped on this.

You are very welcome... now play it until you get bored and then sell it to me. I have a nice spot next to my Baby Pacman for it. :)
 
Nice job getting it working again. I finally got mine working after buying it several years ago. Now that my soldering and diagnosing skills had improved, I felt it was time to tackle it. Does your playfield have mylar on it? Was that standard back then on this game?
 
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