Table lowest point sweep up during spotting pins

[Jan-Willem]

AMF 82-70, MP chasis got a problem after half hour running after spotting pins sweep goes up, table on lowest position with pins on the deck. Ball light goes to first frame. Changed all switches at cams and switched chasis to other lane problem does not follow so it's in the electrical of the machine. Never seen this in the past 15 years also checked al the pins on C2 plug. Is it possible in the off spot switch faulty so it might be grounding ?

[jlww]

could be the table capacitor in the front trunking thats faulty

[Jan-Willem]

The motor starts and runs normal, the relay in the MP chasis switches of when Table is in lowest position so I don't think the issue comes from the motor capacitor. But anyway thanks for youre thought. Normaly this happens after running a half hour and the rest of the evening runs perfect.The solution when it happens to just push the table button on the side of the chasis and runs self to 360 degree stop.

[RTYPE]

Have you checked the cam switch wiring? Possible one could be grounding out somewhere.

[Jan-Willem]

I have changed out all the switches for brand new ones except for the interlock switch of the sweep so also checked the wiring didn't got a new one left any more, but it's not interlocking because I can run the table up with the switch on the side of the chasis.

[Tablejam]

If this was SS chassis and this happened on 2nd ball I would say it's either the ball stepper button in back, OS, or TA2 switching ball cycles while the table is down, which will cause the ball cycle to flip to first ball, the table to stop where it is, and the sweep to run to zero. Since there are several versions of the MP board, I'm not sure but I think one version of it behaves like a SS chassis.

You say you switched the chassis, have you also tried a different MP board?

[Tablejam]

I just caused this to happen on two of my MP machines.

I put it in 2nd ball and started the cycle. Then waited until the table was all the way down spotting (while TB was lifted and before TA1 gets lifted). Then using a long stick I waited until the table was all the way down and flicked TA2.... the result was the table stopped where it was, the sweep ran up to zero, and it switched over to first ball. So that then indicates a possible problem with TA2, could be cam adjustment or something on the cam surface bumping the lever at that moment, could be a switch or wiring issue, could be a weak lever spring, etc. Would also like to know if the problem follows the board if you move it to another machine.

If the TA2 spring is weak enough its possible a sloppy gearbox/table shaft or bad bearings in the table drive or clevis is causing a bump that causes the lever to jump off the switch, pretty interesting that it always happens when the table is in this position and if it is bad bearings since it happens during spotting the table drive eccentric bearings may be dry or shot.

[Jan-Willem]

I left the board in the Chasis when switching to other lane, adjust the cams after changing out the switches next time I will be there start checking wiring other end in the wireway. In my opinion is it the MP boards version 5, the tension on the springs are all right. The strange thing is that it happens on the lowest position of the table when the switches don't change at that exact moment. It's not the daily centre for me so have to go back this week. Happened a couple of times last weekend. I'am also thinking the problem comes from the TA2, ball stepper contactor also a good thing to check didn't think about the BE control box. When I figured it out I will come back with the solution. Keeps the job exciting something new to figure out. To bad they have to run with a small problem since they don't have a mechanic. Normaly there about once every 2 weeks.

[Jan-Willem]

Tablejam just reread you're post will also check the gearbox but quit sure about the gearbox in good condition This year checked al the motors on all machines, I always move a motor with some movement that is in my opinion an acceptable tolerance to a sweep before service a bunch money on parts for the gearbox. But thanks for you're simulations on you're machines. Greatly appreciate you're time !!

[RTYPE]

My money is in the wiring :-)

[DarkDays]

Sounds like the TA1 lever is too far outwards.