Start here:

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

Bally Start up sequence:
Coin is inserted into the game. The coin relay will energize. It will stay energized through its own hold-in switch and a score motor switch. If the credit button is pressed (instead of a coin being inserted) and there are credits, the credit relay will be energized which energizes the coin relay.

The coin relay will energize the lock relay (this turns the general illumination on). The lock relay will stay energized through its own hold-in switch and a delay relay switch.

The coin relay will energize the reset relay, through a game over relay switch (if your game won't start, try cleaning the contacts on the game over relay; a very common Bally problem).

The score motor will operate. This will energize the score reset relay(s). The score reset relay(s) will attempt to clear the score reels to zero. This is done by operating the score motor. Each turn of the score motor will operate the reset relay once, which in turns moves a score reel one position, until the score reel(s) are at zero. If the score motor continues to run when a game is started, there's a good chance the zero position switch on the score reel(s) is dirty or mis-adjusted.

The coin relay, through the score motor, will advance the total play meter.

The reset relay, through the score motor, will reset the stepper units (zero the ball count and player units).

The coin relay, through the score motor, will decrement the credit unit.

The coin relay, through the score motor, will energize the game over latch relay coil.

The coin relay, through the score motor, will energize the 100,000 relay latch coil(s) (if the game supports scores greater than 99,999).

If the outhole switch is closed (single ball games) or the ball trough switches are closed (multi-ball games), a ball is released to the shooter lane through the outhole relay (single ball game) or ball release relay (multi-ball game) and the score motor.

On multi-player games, the credit button may be pushed again to add a player. This time the coin relay will not energize the reset relay. Instead it will (through the score motor) advance the total play meter, decrement the credit unit, and advance the coin unit.

If you haven't seen it, there's a real nice color coded schematic on IPDB.

Do the score reels reset to 0?

Sounds like your Player Unit is not resetting/stepping up properly. Key thing on these EM's is to clean those steppers so that they move easily and accurately.

Your making fast good progress! Excellent-

Its probably worth taking a careful look at the stepper units. Just use your finger to rapidly, firmly, pull the coil in and check to see if the unit indexes up smoothly and INSTANTLY- if there is the slightest hesitation where the unit catches on the step up but even slightly hesitates to move the index gear up its sticky- same goes for reset. If any unit is sticky in any way it can rear its ugly head in game play and do things like- fail to change player, fail to count/award/reset bonus, fail to change ball, fail to award/remove credit etc etc... all of those functions are "computed" or counted by basically- the number of steps a gear has turned.

These are fairly simple mechanical units, if they are sticky you will be able to easily (take your time) remove all the switch stacks and coils so that there are no wires, then just pull it out (2-4 screws usually) of the game- take pictures of every thing as you take it apart, clean it, and use the pics to put it all back together again. This will greatly enhance reliability.

Maybe your game is clean and perfect, but unless someone has done this in the last 5-10 years- its not, its far more likely to be sticky- they nearly all are after this long.

Running through these units is a "simple" fix for an EM that reward's you with clean game play for years to come. You can cause problems for your self if you put the switches back wrong (worse- if they are on wrong first and you do not know it) or gap them wrong- but aside from that, they are relatively hard to screw up- just put them back together the way they were and usually all is well.

Ha- ya never know...

Couple things.

Lubrication is in general not needed in many places. When its is called for is typically metal on metal contact. Not sure how much you have done and know... but since you asked general questions I will provide basic answers - if you knew this then disregard.

Things to never, ever lubricate.

1)Coil sleeves- just don't go here. They cost 15 cents... buy new sleeves for every coil in the game (its going to be 15-20 bucks total). Keep them, and whenever you take something apart replace the coil sleeve- sand the coil plunger until its nice and shiny, clean it with Brasso metal polish, dry it and assemble.

2)Any part of a switch stack/coil assembly

Things you want to lubricate-

USE a teflon based lubrication like TriFlo or SuperLube. Super lube I think is available as a grease type or a liquid. I only have ever used the liquid TriFlo because any bike shop in the USA will stock it so its easy to find locally.

On the stepper units you do NOT need to lubricate the main gear thats doing the counting- at least not on the teeth or any part that contacts it.

You CAN and should lubricate the bushings that hold the gear onto the main assembly, you can and should lubricate the pivot points on the arms that engage the teeth to step up or down the main gear. Thats really about it for those. Every manufacturer builds them slightly differently but its all the same stuff. A gear bolted down to a bushing that allows the shaft to spin. Use the smallest possible amount of lube and work it in mechanically- spin the part, move it, etc. Then wipe it down so no excess is sitting around gathering up dust etc.

The other main place for lubrication in EM is on the wiper units attached to the stepper units. These on Gottliebs are predominantly a bake lite disc with a bunch of brass spring mounted contact points that rotate with the central gear and switch contacts. The contacts should be sanded until shiny (careful not to sand the bakelite)- if they are not worn but simply corroded use Brasso- its safe on Bakelite and does wonders (I go through 2 bottles per machine I shop and use it to clean and polish every single part of anything I take out of the game).

Various people use various things there. Thats typically a place for a grease type lube. I personally use a dielectric grease designed to lubricate electrical contacts like this. Others use the paste version of the Super Lube (TriFlo is not available so far as I know in a paste formulation and would not be a good choice here).

Beyond that- I am struggling to find any other part that needs lubrication but for the score motor. If this is your first EM- I strongly advise that you ignore the score motor until it demands your attention- this is by far the fastest way to generate difficult to solve problems- by "fixing" a working score motor. I know this from experience- just leave it alone until your experienced enough at reading schematics and fixing EM's to at least be able to participate meaningfully in the troubleshooting discussion that will inevitably occur when you put it back together.

Hope this is what you needed.

A very very good place to start, is to find a stepper unit that has an otherwise IDENTICAL or very close to identical unit in the game... then if you work on just one- you have at least some reference point to use to help put it back together. But- these are common basic EM units and many people here will easily be able to help you get it back together if your lost. Like I said and will reinforce here.

TAKE PICTURES from every conceivable angle of the unit in the game, when its in the game you really want to be sure (as much as you can give what you know) that the unit is in the ZERO position before you take pics. Then- be sure to get good quality pics showing the position of the switch stack, which switch is OPEN which is closed and how the switches are hitting the various posts sticking up from the assembly. BE sure to take pictures of the wiper disc position- MARK IT WITH A PEN so you know the correct orientation BEFORE YOU UNSCREW ANYTHING.

One final word of advice. The wiper discs are attached to the central gear- their position is fixed more or less (usually you have two orientations opposite from each other by 180 degrees that it can mount- this is what you need to record). However, the actual contacts are on a large bake lite squareish piece that bolts onto the mechanical- this can be MOVED a few degrees and when you assemble it your going to have to ensure that you adjust it so ALL the wiper contacts are centered (as much as possible) on their zero position contact. Tighten it up so that its held in place but could be moved, and index the stepper up and down checking to see that things are nicely moving from one center contact point to the next in line up and down. Then when its looking good- firmly tighten the screws and you should be good to go.

Beware- you do NOT want to crank down the bolts holding pressure between the wiper unit and the contacts, it will make the stepper VERY hard to move and it will not function.

One last thing I just remembered. There is always a center "clock spring" Photo this- its exact orientation and when you take it off unwind it and COUNT how many turns were put into it to generate the return force (for moving the stepper down) and put it back as it was as a start. Again, if you under wind the spring the unit will not move back easily, if you overwind it - there will be too much resistance for an advance.

Sounds like a lot, but its all fairly obvious once you get one out and play with it in your hands - THATS important. Once you have the mechanical out- play with it for 10 mins and watch how everything works this will be a very good bit of knowledge to have and every single unit is basically the same core mechanical set up with variations but once you get one down the next will go far far faster. They take a couple hours each once you know whats going on- maybe less if its not to gunky.

Finally- I find a citrus degreaser to be a great product for blasting out old black grease gunk. NEVER use this in a game- never put a piece back in a game that has this on it- its flammable- EMS spark... spark+flammable= fire. But- if the parts sitting in your garage on a work bench, have at it with the degreaser it will save you time and very efficiently cleans out old grease.