Burned flipper switch and coil [FIXED... I think]

im surprised you didn't short out the switch matrix with the original problems

from flipperwiki ...


Flipper Coil Gets Very Hot...

On pre-Deger (Time Machine and before) flippers, check the EOS switch to make sure it is adjusted properely (1/8" gap at full flipper extension), and that the contacts are clean and filed. If the coil is getting hot, this means the EOS switch is not opening, or the EOS switch capacitor has shorted on.

I would also still check the other switches in that row/column of the matrix. Make sure they are being detected as closed when activated in test. If you did short something, just testing to see all the switches as open wouldn't necessarily tell you if you have a problem. I would still really recommend tracing back to the board and the related components to make sure nothing is damaged and needs replaced there.
 
im surprised you didn't short out the switch matrix with the original problems

from flipperwiki ...


Flipper Coil Gets Very Hot...

On pre-Deger (Time Machine and before) flippers, check the EOS switch to make sure it is adjusted properely (1/8" gap at full flipper extension), and that the contacts are clean and filed. If the coil is getting hot, this means the EOS switch is not opening, or the EOS switch capacitor has shorted on.

Switches and capacitor are new (which, obviously, doesn't mean they're not defective in some way). The gap is good. I'm going to put a meter on it. I'm also going to check the other switches, as someone else suggested.

I've ordered the correct winding, 2 diode coils, hoping that solves the problem.

UPDATE: I tested the voltage, checked all switches (good), and added a diode to the new coil. It doesn't seem to heat up as quickly, but it's still a bit weak. As I understand it, the installed coils are not quite as strong as the ones spec'd in the schematics.
 
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theres a trick to the gap. Dont adjust it mechanically, adjust it electrically.

In other words, you are going to be able to push the plunger and link assy further than it would be than when the coil pulls the plunger link assy. Reason is, wear. The flipper pawl wears out, the link wears out (on two ends) and the shole thing just doesnt move as far as it should.

The reason your coil is getting hot and possibly frying is because the end of stroke switch is not opening up enough, if at all. The cap is there to suppress the spark that happens when the coil assy disengages the switch. THe suppressed spark is meant to make the contacts on the switch last longer.

The diodes aid in minimizing that spark. That missing diode could help the heat increase, a bit. You dont need to change the coils, just add the diodes. 1N4007's will do just fine.

As others here have said, DO NOT SHORT THAT COIL SWITCH TO THE LANE CHANGE SWITCH. That will fry your switch matrix. Not a good time to repair.

The heat shrink on the cap legs is preventative. As in prevents the high voltage from shorting to shit when the cap breaks off.

YMMV but heres how I adjust that end of stroke switch. Put the game into test mode so you can operate the flippers from the cabinet button. Push the play field up and put the prop rod on the field. Now press the cabinet button for the coil you are messing with. When all the way up that EOS (End of Stroke) should have about an 1/8" gap. If its too close it may not disengage if its too wide the flipper will be weak.

Let go of the switch so you can make the adjustments.

Now heres where you need to be very careful. With a pair of needle nose pliers adjust the blades as needed. Keep in mind these switch blades have 70VDC on them. If you touch them and are touching any other metal in the game you will get zapped. Turn the game off if you feel that its safer (and it actually is TBH).

The lane change switch is supposed to have a red plastic stud on the blade closest to the EOS. That stud acts as both an electrical isolator and an activator of the switch stack. If its missing DO NOT BEND THE LANE CHANGE SWITCHES CLOSER TO THE EOS! Replace that stud.

If all of this has already been covered than oops... If not and you have any more questions please ask.
 
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Are you talking about a literal spark? You shouldn't really be seeing any sparking or arc on the flippers unless you have a corroded EOS switch. I wouldn't make any switch adjustments with the game on, especially around the flippers with high voltage running there. Really you never want to work on a game with the power on. I probably sound like a broken record here but you really need to check out the other switches and your board...
 
There's no spark on the right flipper (after replacing switches and such). I did a switch test on all of the other switches, and they check out.

Right now, it's working, but a little weak. I've concluded that I have the wrong (weaker) coils installed. I've ordered the correct coils.

I'll update when I get them installed.
 
Sometimes the problems are self-inflicted. I was checking the flipper linkage for binding with the playfield upright. They moved fine. During the game, the right one seemed sluggish and would occasionally stick. This time, I checked the flipper with the playfield in the normal position and it was binding. Apparently the weight of the plunger was enough to make it bind. I adjusted the brackets to remove the friction, and it's working much better now. It's still not as snappy as I'd like, but I think installing the right coils should help.

Rookie mistakes, no? :)
 
Sometimes the problems are self-inflicted. I was checking the flipper linkage for binding with the playfield upright. They moved fine. During the game, the right one seemed sluggish and would occasionally stick. This time, I checked the flipper with the playfield in the normal position and it was binding. Apparently the weight of the plunger was enough to make it bind. I adjusted the brackets to remove the friction, and it's working much better now. It's still not as snappy as I'd like, but I think installing the right coils should help.

Rookie mistakes, no? :)

Did you also replace the plunger sleeve?
 
one would be surprised by how much drag a bad plunger sleeve can add.

In newer pins the plunger is pulled downward when the coil is energized. That causes the sleeve to wear thin where it exits the coil to the point that eventually the magnetized plunger is dragging across the steel coil bracket. That adds drag and a lot of it. You wont notice this when you push the plunger into the coil by hand because the plunger is not being manipulated by magnetism.
 
This should help. You could also check the different screws around the plunger. If those are too tight/too loose you can get sluggish returns or play in the flippers. I can get a picture later if that doesn't make sense...

That was the issue. There's a tiny bit of play in the screw holes, and moving the bracket just a fraction of a millimeter causes binding. I played with it until I found the sweet spot.
 
It's always something. I put in the new flipper coil, and the left flipper seems to vary in strength. Sometimes it pops the ball right up there, and other times it develops ED.

I adjusted the mount, and it seemed better for a while, but started doing it again. This leads me to think it's mechanical, but it could have just been my imagination. I'm open to other possibilities.

Suggestions?
 
It's always something. I put in the new flipper coil, and the left flipper seems to vary in strength. Sometimes it pops the ball right up there, and other times it develops ED.

I adjusted the mount, and it seemed better for a while, but started doing it again. This leads me to think it's mechanical, but it could have just been my imagination. I'm open to other possibilities.

Suggestions?

Check the gap on your EOS switch, sounds like it might be too wide.
 
Yep, agree with grantopia here...that's the first thing I would check. Work your flipper with the board up and watch to make sure that switch is not opening until the very last minute.
If it's opening too early you're dropping into the low side of the coil during the stroke.

Check the gap on your EOS switch, sounds like it might be too wide.
 
Check the gap on your EOS switch, sounds like it might be too wide.

Will do. I did replace it and the capacitor because it was sparking like crazy, and one of the contacts was burned off. I thought I checked the gap, but that could be wishful thinking.
 
Cool, hope that does the trick for you.

Just make sure you watch it in action while you're working the flipper. Don't move it manually. I've made that mistake before.
 
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