1964 WMS San Francisco restart issues

Hi guys,

I'm finally working on the SF I got a long time ago.
I am no champion in EM, and I have the utmost difficulties to read the schematics, even though I watched several videos on it...
I do understand the basics though, and I am quite proficient on SS and modern machines.

So, I solved various issues, but am now stuck.
When starting a game, the score reels are reset, a credit is taken, and then it starts all over again, motor and reel are continuously turning, main relay assy is reset, and back to square 1. It'll go on doing this until I take the plug out, even though credits have been depleted in the meantime.

So from what I understand it looks like a contact staying closed, but I could not find it.

Any idea?

#2 3 years ago

MarkG

OP
Quoted from Nihonmasa:
then it starts all over again, motor and reel are continuously turning

Do you mean that the Score Reels keep turning even after they've reached zero? Do they all do it or just some of them? Each Score Reel has a zero position switch that should open when it shows zero to prevent it from advancing past zero during reset.

Each Score Reel also has a second zero position switch that can keep the Score Motor running. The Score Motor will keep turning until it sees all of those switches open.

If the Score Reels do reset properly and stay at zero the next thing to check might be the Coin relay. It should release at the end of reset and allow the Score Motor to stop. Beware that the Coin relay and other parts of this game run at line voltage so extra precaution should be taken.

Do you have a schematic for this game? If so please consider scanning it and submitting it to IPDB.org. They have one but the quality could be better.

/Mark

#3 3 years ago

TIM

TimMe

Vintage Coin-Op Repair

Seattle, WA

9y 62,900 897

In addition to what Mark has suggested, you'll also want to check for a stuck coin switch on the front door.

- TimMe

#4 3 years ago

LAG

Nihonmasa

Guys,
Many thanks for the feedbacks!

When the score reels are reset, they're not turning anymore.
Machine is dropping a credit, lighting the "4" (match unit) resetting the main relay bank assy, and doing this in circles.

Coin switch is fine, coind relay is not activated at all during all this process; I start the game with the start button.

I do have the original schematics, will check how I can scan it to send it to IPDB.

#5 3 years ago

MarkG

These are the switches that will cause the Score Motor to run.
San Francisco Score Motor (resized).jpg
The first one labeled IND. C is on the Index cam of the Score Motor (see the diagram on the schematic). The rest are on relays. Most of the switches will have 30/yellow wire on one side and 74/orange-green wire on the other side.

One or more of these are closed when the Score Motor runs. Which one(s)?

#6 3 years ago

???

currieddog

Pinside member

Springfield, MA

7y 63,550 3,312 6

Check the make/break sw. here.

Capture (resized).png

#7 3 years ago

LAG

Nihonmasa

Ok guys, looked at all the relays and switches above, they all seem to be in the correct positions.
Except the Coin relay, could not locate it (some relays have lost their tags).
IND C is closed/opened as the motor runs, which is normal.

I also noted the following stuff happening during the whole "reboot sequence": A relay activated/deactivated in pulses, same with tilt relay (but tilt latch never activated), change relay same thing.
Also the Ball count is constantly trying to put itself back in zero position.

#8 3 years ago

MarkG

Thanks to Rolf for sending me a better schematic.
I think your Coin relay is stuck on which prevents the reset sequence from ending.
San Francisco Coin relay (resized).jpg
The fact that the Ball Count Unit keeps resetting indicates that either the switch on the Coin relay is closed, or that the Coin relay is active (lower part of the schematic in red). The fact that the Score Motor keeps turning makes it more likely that the Coin relay is active (see schematic in reply #5).

You should look again for the Coin relay. I think B-41 (which is connected to one of the Coin relay coil solder lugs) is a green-red wire and probably PVC covered rather than cloth covered. You'll find the same wire on the Coin Switch for comparison. Keep in mind that it's running at line voltage so only poke around with the game unplugged.

You'll need to investigate what is keeping the Coin relay active. Assuming that the Coin Switch is fine there are two other paths (in red) that can fire the Coin relay. The Game relay is probably in the trip relay bank. You could try blocking a switch in both paths with a piece of paper to see if the behavior changes. That might tell you which path is keeping the Coin relay active.

#9 3 years ago

???

currieddog

Pinside member

Springfield, MA

7y 63,550 3,312 6

OP
Quoted from Nihonmasa:
Except the Coin relay, could not locate it (some relays have lost their tags).

You can match it up by coil # from the schematic.

#10 3 years ago

LAG

Nihonmasa

Many thanks! Will keep on checking

By looking at the schematics I was actually starting to think it might be an issue on this line?

20201130_190738 (resized).jpg

#11 3 years ago

LAG

Nihonmasa

and located the coin relay!
It is constantly locked on when this is happening.
So now I have to find why....
The switches in its stack are ok.

When I have the plug on "2 games for 1 coin"=> I trigger the coin mec switch: it adds credits, no issue. No activating the coin switch
If I have it on "1 game 1 coin", then it activates as soon as I hit the coin switch, and we enter the reset sequence.

Will dig in...

#12 3 years ago

LAG

Nihonmasa

Quoted from MarkG:
Thanks to Rolf for sending me a better schematic.
I think your Coin relay is stuck on which prevents the reset sequence from ending.
[quoted image]
The fact that the Ball Count Unit keeps resetting indicates that either the switch on the Coin relay is closed, or that the Coin relay is active (lower part of the schematic in red). The fact that the Score Motor keeps turning makes it more likely that the Coin relay is active (see schematic in reply #5).
You should look again for the Coin relay. I think B-41 (which is connected to one of the Coin relay coil solder lugs) is a green-red wire and probably PVC covered rather than cloth covered. You'll find the same wire on the Coin Switch for comparison. Keep in mind that it's running at line voltage so only poke around with the game unplugged.
You'll need to investigate what is keeping the Coin relay active. Assuming that the Coin Switch is fine there are two other paths (in red) that can fire the Coin relay. The Game relay is probably in the trip relay bank. You could try blocking a switch in both paths with a piece of paper to see if the behavior changes. That might tell you which path is keeping the Coin relay active.

Need to try the last part of your diagnosis but the first part is dead on! (see above post)

#13 3 years ago

LAG

Nihonmasa

Ok, so I checked the Game Relay, is working fine. Blocked the switches with paper, no change in the behaviour.
I then proceeded in cheking the motor 5C stack; working just fine, no change as well.
Did the same with 4A stack.

So still stuck :'(
Everytime I have checked a switch I made sure it was like in the schematics, and I cleaned the contacts

#14 3 years ago

MarkG

OP
Quoted from Nihonmasa:
Blocked the switches with paper, no change in the behaviour.

Blocked which switches?

What happens when you block the last switch in each of the three paths that lead into the Coin relay coil (Coin Switch, Coin and Replay relay switches) shown in the schematic in reply #8? The Coin relay should not fire under any circumstance. Then if you remove the block on the Coin Switch the Coin relay should fire but fail to remain activated once you release the Coin Switch. If you then unblock the Coin relay switch the Coin relay should activate and stay active for a single 180 degree turn of the Score Motor. Is that what you observe?

1 week later

#15 3 years ago

LAG

Nihonmasa