(Topic ID: 141823)

SOLVED: I need help with Grand Prix Ball in Play stepper

By jmountjoy111

4 years ago

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  • 9 posts
  • 3 Pinsiders participating
  • Latest reply 4 years ago by mrarcade
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#1 4 years ago

To start, this is only the second EM that I have owned so I am struggling. I picked up this Grand Prix project that the score motor would just spin on at the time of purchase. I have been reading and working for over a week and I now have it fully working (super fast and fun game by the way).

However, the ball in play stepper will not step from ball 2 to 3 or from ball 4 to 5. If I manually move it from 2 to 3 and from 4 to 5 it runs perfectly. However if not it just stops. Flippers and coils are still live but not ball gets kicked out and it does not move from 2 to 3 and it will do the same thing between 4 and 5.

I have cleaned it and it all moves freely. I am not an EM genius by any means but I know that there are a ton of them on this site so I am fishing for some ideas.

#2 4 years ago

So does the step up coil fire when at ball 2 and ball 4? If it is firing, do you see the ball two light go out then came back on? If this sounds like what is happening, make sure there is no sticky stuff on the drive and stop pawl. Inspect the teeth on the ratchet gear, too.

#3 4 years ago

No coil fire. No lights flash. It registers the bonus for the ball but nothing else. Driving me nuts lol

The gears all seem fine. I can manually move it through all balls and it will go through them all on its own except those two

#4 4 years ago

Does this happen in both Multi player and single player? Just trying to narrow things down.

As a single player game, it is odd that it will step from one to Two but not to three.

Below is the ball step up schematic snippet. The red is the path of all the balls counting up in a single player game. As you can see, all balls are dealt with same here, only multi player is different.

So check to see that the outhole Re is energised after ball 2 drains and bonuses collected.

#5 4 years ago

In Multi player the game will transition from player one ball one to player two ball one. It then resets to player one ball two. At the end of player one ball two the game collects bonus but stops there. It will not even move to player two ball two. Thank you for your help by the way

#6 4 years ago

But!!, does the Outhole RE Energise after ball two? We need to find which SW is not in the right position after ball two drains. Then we can trace it back. I expect we will end up at the zero SW on one of the bonus units.

#7 4 years ago

You were such a big help and I appreciate it greatly. I checked the Outhole relay and it did not fire on the end of ball 2. I then went and looked at the right bonus stepper and sure enough the switch was out of sync. I adjusted and played a perfect game for the first time. Thanks a ton. These old EMs are fun to play but I have lot to learn about working on them.

#8 4 years ago

Cool!! anther working EM!!

3 weeks later
#9 4 years ago

I hope someone is still following this thread...

I am working an a Williams Aztec. The ball count unit step up coil never fires. It seems the player unit step up fires instead. Here are sequences I have tried/witnessed:

start 1 player game, score, drain, advances to player 2 ball 1; score, drain, advances to player 3 ball 1; score, drain, advances to player 4, ball1

start 2 player game, score, drain, advances to player 2 ball 1; score, drain, advances to player 3 ball 1; score, drain, advances to player 4, ball1 (same as 1 player game)

cannot start 3 player game or 4 player game. stepper can be manually advanced to 3 or 4, but will not advance past 2 using the start button

I did not look at the bonus unit zero sw, could that cause this? I will look at that sw tomorrow. any advice is greatly appreciated. I will start a new post, I am just hoping someone from this thread might have insight.

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