I can't believe you own 7 pinball machines and don't own an ohm meter - how can that be?! You can buy them for as little as about $10 anywhere, just google ohm meter or multimeter. I personally would spend at least $50 and get a decent one. Make sure you get one that has clip on leads at least. Mine has probes that you can screw the clips on. Are you sure you can't just borrow one from a friend or neighbor?

Another option would be to ship the machine down here to Florida and I could do the testing for the price of postage.

You know I'm just kidding with you, right? I have rebuilt the relay and it steps through all positions with no hangups now. It actually wasn't too bad when I got it, but it is "optimized" now. I put a very thin layer of Steve Young's magic contact disc "butter" on the wiper boards as well - I have always had good luck with that stuff. So, I'll box it up and get it in the mail tomorrow. Since the bonus scoring was sometimes marginally working before on your game - who knows - this might be enough to put it over the hump. I have seen stranger things happen. Think positive and good luck!

The problem is on the bonus countdown, right? Id be looking at the switch in the o relay that’s in the schematic clip that you shared. That’s what gates the score motor pulses to the stepper.

You’ve also got 2 Jones plugs in the circuit between the motor board, the backbox, and the stepper. This machine looks remarkably clean, but those connectors have a way of oxidizing over the years. There’s lots of debate on the best way to clean them. I’ve done alcohol and a scotchbrite pad, a dremel brush, and most recently, CLR (calcium, rust, lime remover) all with success.

Dave

The circuit that pulses the stepper for bonus scoring is highlighted in red. No "O" relay switch in that branch. If you are looking at the other branch with the "O" relay switch, that is a recovery circuit to reset the "I" relay back to it's home position, if for instance, you install the relay without having it in the home position or the machine was turned off in the middle of scoring bonus. I didn't show the rest of that branch, but it is in series with the 5-impulse SCM 1A switch. It would send the required pulses to "home" the stepper in one score motor cycle. That is the only purpose of that branch of the circuit - it normally never gets used.

I almost hate to tell you this, but the double bonus advancement is made by the "J" relay, which is... another "AS" relay. It closes a switch on every other score motor cycle to "make" the circuit for the "I" relay to advance. If it is sticking intermittently, then you experience what you are seeing. Advance it by hand to see if the problem is obvious. This one doesn't have wiper boards so it is bit easier to adjust. Also, this one doesn't have a jones plug, so you can't remove it from the game unless you unsolder it.

As for the ball advance problem you are talking about, I don't think that is a problem. On the first ball of the game, you must score points (the 10, 100, or 1000 point relay must be energized at least once) in order to pull in the "U" (First Ball) relay. The player unit will not advance until the "U" relay is energized. The reason for that is that the trough switch normally triggers the player unit to advance, but you don't want that to happen the first time the ball is kicked to the shooter lane, otherwise you would be at ball 2, instead of ball 1 at the start of the game.

If your not getting a big enough "bite" when you pull the armature back, that will definitely make it stick. You should be clearing the next ratchet tooth by about "1/2 a tooth" so there will be no doubt that the finger will engage the next tooth. In other words, you want the finger to "overtravel" on it's stroke to make sure it engages the next tooth when released. One of the reasons that it can look like you don't have enough "travel" is because the ratchet spring is not adjusted correctly. If there is too much "backlash", what will happen is that when you pull the armature back the drive finger will drag on the ratchet teeth and actually rotate it backwards slightly, so you think you don't have enough travel, but because the ratchet rotates back a "half a tooth", it looks like you need more "stroke" but you really just need to minimize the backlash and the stroke will automatically increase as a result. You can check the backlash by lightly turning the ratchet in the reverse direction by hand. There should be some "play" (also called backlash) - but just a little "play". Check that first. The ratchet spring has slotted holes (2 screws) to adjust it. Before you adjust it, use a Sharpie or a scribe to mark it's original position for a reference point and so you can set it back there if needed. You won't have to adjust it much.

Btw, I doubt if you would be able to find one of these specific for your game. They come in all kinds of configurations (different cams, wiper boards, switch stacks, etc).

Hope you got it working @MiloMV. If not, I am confident you can get it working yourself, if you study it and mess with it long enough, but you can send it to me if you like and I'd be happy to adjust it for you (or perhaps send it to someone closer to you like dgAmpGuy so the turnaround time wouldn't be so long). Of course, you would have to unsolder/resolder it from the harness, which is very easy (assuming you have the equipment to do it).

One minor note to add. In refurbishing a Card Whiz, had a similar problem. After doing everything possible to adjust and clean the I relay to get it to work correctly. Was still not always having the pawl catch. Finally traced it to the motor switch. It was adjusted with too large a gap, so was sending a very quick pulse to the coil which didn't allow a long enough full engagement of the coil and therefore pawl. Adjusted it correctly, and problem solved as the coil received a "full" pulse.

That's good info, DCRand. I've seen score motor switch dogs that were in the wrong position, which will completely change timing, but not a mal-adjusted switch - they're usually a go or no-go thing. Interesting. Maybe that's the reason it originally wouldn't work in his machine but worked fine in mine?

That sounds like the same condition golfer Jason Day has. I remember a few years back when he suddenly fell down during the U.S. Open and Greg Norman was talking about crystals in his ear canal causing the dizziness.

When you get back to it, maybe you want to take the playfield out of the machine and put it on a table to make access easier/more comfortable to the relay. It's just 3 connectors.