I may have missed this.....There is a switch blade on the score motor that acts as a brake for the motor. If that blade breaks off, the motor will spin constantly. This is a common issue with Gottlieb score motors. If the "brake switch" does not do its job, the score motor will overrun its stop position and reactivate the motor looking for the next stop position which it will also run past etc. etc.

Something simple to look for and rule out. It is on a mount all by itself and has no wires running to it. The blade should "grab" a pin on the motor plate at each of the three stop positions.

Thats the brake switch I was talking about! Get a new one and put it in before you try messing with anything else. It is not an electrical switch that tells the game anything. It simply applies drag to stop the rotation of the motor so it does not overrun its stop positions.

The three notches in the top plate of the motor are the stop positions. There are three pins that extend out of the bottom of that plate. The brake "Switch" will catch on these pins and help stop the motor

Can you post a pic or video of this? I'm not sure I understand what you are describing.

Great! looking forward to seeing it.

*sarcasm* The video seems a little hard to watch. *sarcasm*

I don't see a link to it. You need to post your video somewhere like youtube and then put a link to it in the body of your post here on pinside. As far as I know, you can't directly upload video here like you can with a PDF or JPEG etc.

Its been a long time since I posted here in the EM forum. I'm by no means an EM expert but I do have some good experience with hands-on, learn as you go, pinball repair. Here are a couple links to valuable EM repair guidance. I learned a lot from these documents. Hope they help you too.

http://www.pinrepair.com/begin/index.htm

http://www.pinrepair.com/em/index.htm

Do you have the schematic for this machine. Sorry if I missed this.

Find the ball in play unit. If you're lucky, the stepper units are still labeled. not sure where you will find it but I would start in the backbox. It will look similar to the player unit identified earlier in this thread. make sure it is stepping and resetting properly and that the switches open/close properly at the beginning and end of the stepper cycle.

If QB is the game over relay, I think the ball unit could definitely be the culprit. it tells the game that the last ball has drained and to fire the QB relay. Since this is a multiplayer game, this signal may run through the player unit too. also check all the switches and wiper contacts on the player unit for anything out of the ordinary. I know this is vague. Hard to do without schematic.

That pic is of the match unit. It steps constantly throughout the game as 10 point targets are hit. Back up a bit and take a pic of the entire backbox.

The stepper up high in the center. I believe it is hinged at the bottom and will tip out toward you. There may be a screw or two at the edges or maybe only a retaining clip holding it up. figure out how to lay it down towards you and manually operate it. Make sure it operates freely on every step and resets completely. When you lay it down, you will see a few contacts that are either opened or closed at the beginning and end of the stepper range. Check those too.

Caveat: It has been about 5 years since I have really poked around at an EM machine. I love this stuff but am running kinda blind on this one because of the lack of schematic. If you are going to keep this game, I recommend getting one. They can usually be found at pbresource.com since this is a gottlieb machine.

Checking all of the steppers is always a good thing to do when you get a machine that has been dead for a long time. This includes all the score reels too. There are a lot of contacts that need to make and break at just the right time in these things. Read through clays guides to get more info about how to clean and adjust these steppers.

I've got to hit the road for now. Will check in again this weekend. Sorry to leave you hanging. Hope I have helped at least a little.

guessing that is the player unit. There are more steppers under the playfield and inside the lower cabinet.

Great stuff guys!! Pics help a lot. I see something on the credit stepper switches that looks a little funny. May be an issue or may be just me. Take a look at the single switch. It’s meant to be an upper limit or max credit. It looks to me to be open. Hard to tell for sure from the angle of the pic though. It should be closed normally and only open when the credit stepper pin hits it after a high number of credits is added. Close that switch and see if it behaves differently for your credit situation when you reach one credit left

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Great thread. Lots of good info here. Pinball Brian, lets get you going now! Can tell Bonzo has a great deal of experience to draw from here. I’m enjoying the learn.

Still here! Still interested!

Take the paper out of the H relay and send a close pic of the contacts from the side. So all switches and the white plastic ladder can be seen. Check all the wires soldered to the switches to make sure none of the terminals are physically touching, Sometimes its something as simple as that. Send me a scan of the schematic or overlapping pics in a PM. Don't post Gottlieb Schematics on Pinside.

Something looks funny to me on the add bonus relay. Like the armature is out of position.

sorry im slow but havent left. Ill stick with you until we get it running. How good are you with a multimeter?

post some pics of all the fuses if possible. labels on the fuses if they still exist. I want to see wire colors so I can identify the fuses.

Thanks Bonzo!

And the one that blows when the tilt hold relay "H" is activated is the one labeled "3" with blue sharpie?

That fuse should be a 10 amp standard fuse

very nice of you to say Nikrox2. Don't put me too high up on that pedestal. I'm a noob compared to many EM guys here. Love this stuff though. Hopefully this was just a wrong fuse situation. If not, we will start troubleshooting. I don't currently own any EM machines so I have to play with others'.

always have machine turned off when connecting and disconnecting the jones plug connectors.

OK. Lets take half of the machine out of this equation. There are 4 (i think) wire harnesses that come up from the cabinet to the backbox. unplug all harnesses from the backbox. Also, leave the playfield unplugged. turn on the machine and watch that fuse.

If no fuse blows, then the next step will be to plug in the playfield and try again. Dont forget to power off while messing with connectors.

THen one backbox connector at a time, etc...

note when the fuse blows and let us know.

https://pinside.com/pinball/forum/topic/em-pinball-circuits-basics-to-not-so-basic?tu=SteveFury

take some time to read through and study this topic. It is FULL of great EM circuit help

Got it. I had Hot Shot (4-player version) stuck in my head. Yes, the issue is somewhere in the bottom cabinet. Disconnect the playfield and lift it out of the way to make room and get a good flashlight and multimeter ready. Your eyes are your best tool right now. Inspect all wires where they are attached to switch terminals to make sure no bare ends are touching that should not be. Start around the tilt hold relay. go slow and check every terminal on every relay. look for any obvious repairs....electrical tape, wire nuts, other things that seem out of place. Then we will start checking continuity (beep) with the meter. This may get a bit tricky so be patient.

Wait!!! get us a closer pic of the wire harnesses coming up from the lower cabinet. I just looked at your backbox pic again and noticed the duct tape around one of the harnesses and the apparent repairs on the other one. Lets look closer at those! your wires could very well be shorted inside there due to a previous repair. lets see those closer up.

Also, take a close look at the stepper in the center of the backbox. It looks like is is not mounted properly, may be shorting against a wire or metal bracket on the score reels. It looks crooked and wrong to me.

Look at this one. I know its more crowded but see how straight the stepper in there is mounted? This is nik's Hot Shot

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This is Fun, I've missed this. I'll be offline for a while. Will try to check back later tonight.

Start by straightening out that stepper unit up between the score reels. Make sure it’s mounted properly. Try to start the game again after that. If that doesn’t work, we can dig deeper into the connectors and harnesses.

I like it. Try to run the game with the coin door unplugged. You really should fix the duct tape repair on the head harness though. Verify that the game runs with the coin door unplugged. That will isolate the short to that area. Once you are ready, like you did before, go after that wire harness but use heat shrink tubing instead of electrical tape to insulate the open wires at the solder joints. Buy a big box of tubing st harbor freight for a couple bucks. Electrical tape will turn to goo after a while and possibly move. Plus, the heat shrink repair will look much cleaner.

Don't hack it at all. We will just find the problem and fix it. Then we will set the game for free play. I'm just curious if the whole game will come on without the coin door plugged in. We can start a game manually. I can help with that. Assemble the machine. Plug everything in except for the coin door. Power it on and let's see if anything blows. Then we will manually trip the relay that the start button activates.

Try to manually engage the "Y" relay. It is called Replay Button Relay.

Don't forget about that stepper in the backbox. It may not be causing problems now but I fear it will if you don't get it mounted correctly. See the picture of a Big Shot attached for reference.

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with the coin door unplugged, use your multi meter to test resistance of the coin lockout coil in the coin door. Set your meter to check resistance "ohms" and set it to a range around 100. put the meter leads on each of the two wire terminals of the coil. Not sure what that coil should read. Probably 10-30 ohms. If you get something really low like 1 or even 0, There is your short. In that case, remove the black wire from the coil and wrap it in electrical tape to keep it from shorting against anything else. Plug in the coin door connector and power up the machine.

Looked it up, That coil should read around 25 ohms.

The coin chute lights are in circuit with the fuse that keeps blowing. See if you can follow the wires from the lights back to the plug. Set your meter to 100 ohms and touch your meter leads to the pins on the plug for the chute light circuit

Ok. Help me identify wire colors.

Red arrow looks like black with white to me

Green arrow looks like black with red (extremely faded) to me

Blue arrow??? Can you tell me what that wire is?

I was wrong about the lights. They are above the coin door on the cabinet.

I think we may be chasing the rabbit down he wrong hole. It won't hurt to unscrew those wires that are together by the total counter though. Separate them and try again. If it still behaves he same, then put those two wires back together.

How many credits show on the credit reel in the backbox?

That coin door tilt switch needs to be adjusted so it is normally closed.

There are two different types of tilt switches. The plumb bob one in the front left of the cabinet is an open switch. When it touches the metal ring, it closes the circuit and starts a sequence that ends the current ball. The other tilt switches are part of the circuit that keeps the game running. If these switches are activated, by a hard kick to the coin door or a lift of the machine and drop, the entire game n play is ended. They are called anticheat switches and are typically closed. You might find another switch like this mounted under the playfield and/or on the relay panel in the bottom of the cabinet.

Does the game have credits on it? Does the credit wheel show something higher than zero?

Does the score motor ever turn when you manuall activate any of the relays?

Try to manually turn the score motor just a little bit in the counter-clockwise direction, it should take off on its own and rotate for a moment until it reaches its next stop. ( this test must be done with power on) be careful what you touch and be careful not to damage the switches around the score motor.

Happy Thanksgiving all!! Won't have a lot of pinside play time today, but I'll check as often as I can.

I’m going to look closer into the score motor circuit. It should turn once you rotate past its stop. Could need some switch cleaning/adjusting around the score motor or maybe a blown fuse. Will need to look at the schematic. I’ll try to make clips of the schematic and mark them up for you as I go. Not sure if I’ll have time today though.

My feuds won’t happen till tomorrow at the in-laws. Lol

Grab your schematic and find the drawing of the score motor. There are 3-4 stacks of switches that surround the motor plates. We are looking to identify and clean switch 1C. When the motor rotates to one of the three cutouts, tha motor switch 1C will open. As soon as you move the motor out of position, the switch 1C will close and power will go to the motor causing it to rotate until that switch drops into one of the three cutouts again. This opens the switch and cuts power to the motor. Clean that switch and test the motor. It should run no matter what else is going on with the game. Unless there is another blown fuse (possible) or if the motor is bad (super rare). Switch stack 1, level C. There are five possible levels of switches starting with the lowest level A

Good stuff. Thanks!!

Looking closer at the schematic, I see three tilt switches that are normally closed. Three that are open.

Really like the suggestion to check the reset bank switches.

So still no score motor operation at all?? There is a fuse in line with the motor. It is a 10 amp fuse. The two wire colors attached to the fuse will be Solid Red on one side and Red with Black stripes on the other.

There is also a bounce switch in line with the motor circuit too. It should be normally closed and the wire colors are, Red with Black stripes and Red with White Stripes.

Red wires are almost always faded and very hard to see, so use a warm flashlight to verify wire colors if needed.

post a well lit pic of the score motor from above, close up and backed out a bit.

HotShotSchem (2)_LI.jpg

Notice all the open switches on the schematic up by the Motor 1C switch. If any of those switches closes, even momentarily, the score motor should start running. W, C, D, E, O, Q, S, U, SB1, SB2

W = 2nd Chute Relay
C = Add Bonus Relay
D = 500 Point Relay
E = #8 Hole Relay
O = Ball Return Relay
Q = Ball Return Control Relay
S = Start Relay
U = Control Bank Reset Relay
SB1 = Reset Control Relay (in reset bank)
SB2 = Reset Control Switches (also in reset bank. no coil associated with these switches)

All of these are normally open, Any of them close and the score motor starts turning. The motor is kept turning by the Motor 1C switch until the motor reaches its next home position.

There will be multiple switches in these relays. You can use the schematic to identify these switches by wire colors. All of them will have Brown with Red Stripes on one side and Red with White Stripes on the other.

All that being said, You have manually triggered a few of these relays already and the score motor has never started running. I suspect the fuse is bad.

It’s this fuse. 10 amp fuse. Now that I look closer, the fuse holder looks bad too. The fuse may be good but it doesn’t matter if the holder is loose. Check that fuse and the holder too.

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Thanks bonzo. Good advice. I bet that fuse is good and the problem is a bad fuse holder in this case.

According to the schematic, that fuse with those wire colors is a 10 amp fuse.

Bonzo is right about a shorted coil blowing fuses. Definitely could be part of your problem but In your case, I would bet the fuse holder is the culprit here. Check and repair that first. I expect your machine to jump to life soon!

I certainly don’t mind any additional help/wisdom and neither should anyone else. It’s fun trying to help others get their machines running and also quite a challenge doing it without being able to physically see/touch/hear the machine. Thanks so much for chiming in. Do you have a Big Shot schematic?

Sweet. Do you see the same thing I see with that 10 amp fuse? Looking at the pic of his fuses it looks like the upper clip on the holder is weak and spread open. If that’s the case, of course the motor won’t run.

Brian, I understand your concern. I want to try to clarify all of your fuse questions.

Answer for me this. Have you posted a pic of every fuse in the game? If so, I will go through all the pics and cross reference them by wire color on the schematic and label the pics and repost them in one post for you.

OR........

If someone else out there has a Big Shot and would be willing to help with the fuse confusion........??

I’ll start working on the pics of fuses you have posted. I agree that there seems to be more fuses on the schematic. Brian, doublecheck to see that you have indeed posted pics of ALL fuses in the game.

In addition, find all the slam tilt switches and post close up pics of those. Look in.....Coin door, control board, under playfield??, in backbox. I want to see the wire colors on those so I can help you determine if they should be open or closed.

I noticed that the coin slots are gone. I wonder what other “mod/hacks” have been done before you got this game.

That looks like all the fuses. Your pics match up with the schematic.

The four under the playfield are all 2 amp slo blo. They are part of the target bank reset circuit

The three by the tilt me h are all 10 amp standard the two on the right (2, 3) are playfield and backbox lights. The one on the left (1) is the score motor. Even though that fuse is good, make sure you have continuity through that fuse holder. Test at the holder solder terminals. It looks funny to me, like someone has added solder inside the fuse clip.

The one labeled primary fuse is correct. 5amp slo blo

The one labeled bank setup is also correct at 10 amp slo blo

That’s all the fuses according to the schematic. I bet the two you are missing when looking at the schematic are on the left side of the schematic just above the listing of “relays”

All total there are (4) 2a slo blo, (1) 5a slo blo, (1) 10 a slo blo, and (3) 10a standard fuses

Will get back later on the slam switches.

wire colors match up on all but the coin door switch but I’m sure of the text I put on the pics. I wonder if the coin door isn’t original.

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Making progress and seeing some signs of life! Good news. You said the score motor turned a bit and then stopped.

What happens if you manually turn the motor in the counter-clockwise direction? Once you move it enough, it should take off on its own and make a 1/3 rotation.

If the motor behaves like I described, let’s keep that motor moving. Sometimes after cleaning switches, they need to be worked a bit to finish cleaning them. The more you use EM machines the better the switch contacts become (to a point of course). Try to get the score motor running by manually actuating the start relay “S”. Do that over and over for a while. You might just find that slowly more and more of the machine will wake up.

Don’t see a video. I’ve had good luck posting videos in the past on YouTube and then posting a link on pinside.

Are all the 2a slo-blo fuses installed and good? Do you get continuity across all four fuse holders? Those fuses are for the drop target reset circuits

excited to hear results.

Looks good. Do I understand correctly that the credit button on the coin door still doesn’t start a game?

What happens if you manually actuate the “y” relay. It’s the replay button relay.

Use an alligator clip jumper wire. Make the jump around this fuse as shown in the picture. Attach to the fuse holder lugs. Then try the start button. Then try the “Y” relay if the start button doesn’t work.

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When you manually turn the score motor counterclockwise, it starts turning on its own and makes about 1/3 turn. Confirm if this is correct. If so, we need to start checking switches. We can do it with a multimeter set to read 25v dc or we can try jumper wires using the schematic. Let me know for sure the score motor runs.

We can wait on the meter for now. Make sure that there are some credits on the game. There is one switch that needs to be closed when the credit unit moves above zero. That switch is in the “y” relay circuit. Make sure it is closed and then try the start button again.

To start, focus on the zero position switch on the credit unit. Make sure the unit is greater than “0” and that switch is closed. Then focus on switches on the “y” and “s” relays.

If all is right, pressing the coin door button will energize the “y” relay. The “y” relay has a switch that will energize the “s” relay. The “s” relay has a switch that will start the score motor.

Clean and adjust all the switches in this post. Credit unit and “y” and “s” relay switches

It’s all good. Take your time. It’s cold and snowy here. Not going anywhere!

What did you find on your 10k problem nick?

Looks really nice. I love the wear around the flipper buttons. Shows the love this machine got in its prime.

Coin lockout coil on coin door should engage as soon as machine powers up. Thats normal.

check your switch positions on the left target bank. Compare them switch by switch with the right bank (under the assumption that the right bank is correct. My guess is something on the target bank may not be opening when it should as the bank resets.

There is an additional switch where I have circled. I'm not 100% sure but I think those close when all targets are dropped and open when targets are reset. If this stays closed even after targets reset, you might get the symptom you described with the constant reset.

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If it only overruns the motor when the playfield is plugged in, then we need to look for other things on the playfield that cause the score motor to run. I’ll look some more at the schematic tomorrow. Those drop resets are on the 25 volt circuit. Look at the bottom of the schematic and see what switches are involved in drop target reset. Start investigating there.

1) When you turned it on with the playfield installed, was a the playfield down and a ball installed in the outhole?
If "YES" then move on to question 2.
If "NO" then try the game again with a ball in the outhole, and then move on to question 2 if needed.

2) You said the game started but the motor kept spinning and it looked like target bank reset kept cycling. Did the machine send the ball to the shooter lane?
If "YES" and the game kept cycling even after the ball went to the shooter lane, then check the runway switch, (Located at G-3 on the schematic) between the outhole kicker and the shooter lane. That switch should open as the ball rolls over it on its way to the shooter lane.
If "NO" check the contacts on the outhole switch and the switches on the "O" relay. We need to get the outhole solenoid firing.

I understand your concern. When you took the playfield off, the motor turned 1/3 and then stopped? If this is the case. I think we need to stay focused on the playfield. The constant drop reset may be a symptom of something else. If you checked all the drop switches and they are adjusted properly, I'd move on from that. Take a closer look at the outhole switch contacts making sure that they make good contact when the ball is in the outhole. Then look at the "O" relay and make sure all switches there are working as they should be.