Goodmorning everyone. I have an Italian copy of TEN UP Gottlieb pinball machine TEX OP. It is for one player only (add a ball). Unfortunately it doesn't have a schematic but the relays and connections are very, very similar to the TEN UP. In fact the relays that give me the problems are exactly in sequence like those of the TEN UP.
While you are playing, sometimes, when the holes at the top (hole relay) are activated the motor makes one revolution, sometimes continues with the loop (ta ta ta ta ta) or makes one more revolution sometimes 3 sometimes 5 and most of the time nothing.

This loop with the "ta ta ta ta ta" does it in these other three cases:

1) when the ball return relay is activated
2) when the wow relay is activated
3) when the sequence completed control relay is activated

Cleaned and adjusted all engine contacts but without definitive results or improved but not resolved.

Are there any other contacts affected besides the motor and its relays?

I attach the link of the video so as to give a better idea.

(sorry for the google translation ....)

Updated information

That's right, all right in the description he kindly gave me.
Now I wonder (I don't know if he saw the video) all the tests I did, they were on the other three relays that give problems (return relay - wow relay - sequence completed control relay) but these complete an operation (ejection of the ball in the launch channel - add a ball - reset targets) but do not give scores.
This is why I don't understand where the defect could be, especially in my case that the connections have a logic perhaps equal to the king Pin but with different wire colors ...
What can be on the King Pin that contact you referred to me that is activated for a moment and basically stops the engine?
I hope I have explained. Thanks Marco

Thanks for the suggestion but the contact 1A is well adjusted and cleaned, so much so that the 500 or 5000 points marks them perfectly, always. Unfortunately it is the random spins (1 more or 2 or 3 more or none) that when he decides he does them. In fact, in particular on the ball return relay, operating it by hand causes the defect. Putting a piece of paper on the motor contact (4C for me) no longer does the defect but, obviously, the ball return relay does not trip.

Thank you.
Contact 1C should not be. In fact, turning the engine gently by hand ALWAYS only makes a third of a turn.
At this point I would check the 2B.
Unfortunately, I've had pinball since February and I'm not really a good repairman.
How do I find the 2B?
I saw that there are 5 positions in the engine (1 - 2 - 3 - 3 1/2 - 4)
In my case there is only 1 - 2 - 4
The letter indicates the position of the blade group (contacts) starting from the bottom A, then B and so on.
So for example contact 2B you mean the 2nd position and therefore the B for the second pair of blades of the position 2?
I am attaching the photo of my engine
Thanks Marco

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Thanks, now the question of the engine is much clearer.

However I believe (I hope) to have solved.
The problems were two of which one created by me.
The main one was the contact of the ball return kicker, in fact the pivot of the movement had loosened so much that many times, with the game it had, it touched the contact (as if the ball touched it), so the relay was activated several times or once only ...
With this problem not seen, looking for other solutions, I had noticed (my mistake) that with the engine at rest, the natural play of the switches in position 4C tried by hand, you could see an excursion of that row of switches that worried me ( seemed to touch).
In reality they are activated only with the engine running ....
Then I had pushed them away a little, just enough unfortunately that they didn't work as they should.
I gave it back a distance of 1/2 millimeter and everything seems to be going.
On the 4C line there are precisely the 3 relays involved
(return relay - wow relay - sequence completed control relay).
Thanks for your patience.
Marco

Thanks very much

Goodmorning everyone.
I still apologize but the problem returns.
Obviously there is no perfect synchronism between the reeds with the advances and postponements of the engine.
Always the three relays (return relay, wow relay and sequence completed control relay) when they are excited in the game (but also by hand or by making contact with a screwdriver in the reed that activates them), the motor continues to make one or more turns ( 1/3) and then stop and sometimes it only makes a third of a turn perfectly ....
I think I have identified the motor self-excitation in 1C the first NO contact that closes for the entire third of a turn but that does not seem to me to be the problem since I tried to isolate it with a piece of paper.
Instead, I think I understand where the problem arises, that is in the contacts of 2B.
There are three NO contacts that open at the third of a turn, while the only NC contact on the same row closes.
Evidently (but not necessarily in 2B) there is a contact that should open to remove current from the excited relay and that either does not open, or opens late ....
I added by soldering a piece of lamella that still keeps contacts 2B active for a few fractions of a second but it didn't help much.
I remember that being an Italian copy of the TEN UP or KING PIN it does not have a pattern, although it is practically the same as the original.
Can you please understand which contact is not opening well or late?
Thanks Marco

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