drop bank issues!!!!!!!!

spanks_4

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I have been fighting with this damn assembly for the past few weeks and i'm just out of ideas!

Ok I pulled the thing completely apart, cleaned everything, replaced targets, replaced springs, and replaced sleeve!

When the PF is up I can ALMOST get the top of the targets level with the pf before the coil won't shoot them back up. Ok fine I can deal with that, but when I put the pf down, push the targets, and the damn assembly starts struggling to push the targets up and won't, lift pf and works fine! The arm doesn't seem to be binding at all and it slides in/out the coil fine.

The top of the targets are supposed to be level with the top of the PF and I can't get them to that point. Anyone know what the hell is wrong with this damn thing?
 
The coil in both of my LAH machines matches. Is it possible for a coil to get weak over time?

Edit: Per the manual the 23-700 is the right coil so no clue what to do!
 
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Manually ground the tab of the driver transistor for that coil. If it's still weak there is a connector or mechanical problem. Could even be the wrong coil or a bad coil but seems unlikely. Especially if it was working before. If it's strong when grounded manually I would replace the driver transistor.
 
Well the thing that throws me off is if the playfield is up *resting on back box where I can get to the assembly* it will fire the targets back up like it's supposed to, but when I put the pf back down it starts struggling again.

I'm going to try the ground thing you mention Lindsay first then I guess I will try putting the old sleve back in and see if maybe the new sleeve is causing the coil to bind or something.
 
My guess is it the targets are binding on the side of the playfield and aren't when it is in the up position. Try repositioning the bank.
 
The bank is sitting where it should so that's not the issue.

The coil is the right coil per the manual. I grounded at the transistor and it still struggled. Is it possible for a coil to get weak with age? I usually have them either work or not work.

If it is then would it hurt to put like a 23-800 instead of a 23-700?
 
The bank is sitting where it should so that's not the issue.

The coil is the right coil per the manual. I grounded at the transistor and it still struggled. Is it possible for a coil to get weak with age? I usually have them either work or not work.

If it is then would it hurt to put like a 23-800 instead of a 23-700?

Try grounding it manually right at the coil. If it's still weak it's either the coil or the mechanism.

Coils don't get weak over time but it could be partially shorted. If it's in the mechanism you should be able to feel it when moving it manually. Try dropping the targets and resetting them manually. The targets could be dragging or something.
 
1.) Pull the coil sleeve out and use a q-tip and water and clean it up. If the coil sleeve is tight then the coil has simply been over heated and the coil sleeve distorted. Replace BOTH!
2.) While coil is out examine the plunger and link. (speaking in general here since I'm not familiar with that drop target bank) but if the plunger has any mushrooming happening at the bottom sand it/smooth it. If the plunger link is fairly worn it would also make sense why "gravity" is playing a part in this. Changing the angle would allow it to move more freely if binding is occurring.
3.) Clean the leaf spring contacts. THAT will greatly reduce the spunk of a coil.

It's an age old argument but I've seen it first hand where a coil has simply lost some of it's spunk. When a person can replace and clean everything and it's still weak and then lastly changing the coil and it works ... well ...(shrugging shoulders) ;)
 
The way this one works is it resets once all of the targets have dropped. The sleeve is very tight inside of the coil *putting it in* but the plunger slides in/out like like a penis inside a very lubricated hole.
 
If it is then would it hurt to put like a 23-800 instead of a 23-700?

A 23-800 will be weaker than a 23-700. The first number is the wire gauge, the second is the number of turns. Larger gauge wire (smaller first number) is stronger, and fewer turns (small second number) is stronger. The general rule is less resistance = more coil strength. So larger wire and fewer # turns = stronger coil.

Do you have another coil in the game that is the same gauge and # turns? If so, compare resistance measurements between the two coils. Unless there is a physical short in the coil, the problem is most likely somewhere else.
 
Thanks for the clarification Stang!


Well I was replacing bulbs and my apron row is completely out. So here we go with a new issue!
 
You weren't replacing bulbs with the power on, were you?

RussM

Nope, but I have done that before with no issues.

Well I fixed the magnet issue *replaced chip *put in a socket* and replaced the three transistors* and they are pulsing and doing like they're supposed to!

So drop targets and that row of lights and i'm done!

Curious: A friend said that hes had coil stops get magnetized and cause a similar issue before. Could the stop possibly be magnetized?
 
Ok the actual coil stop is magnetized and so is the piece of metal it screws into! The piece of metal it screws into doesn't affect the bank from going up/down, but with the stop being magnetized could it aid in the issue with gravity? Any way to demagnetize the stuff?
 
The plunger seems to be magnetized along with one of the brackets that holds it to the playfield.

I'm going to buy a new coil, stop, and plunger so if that doesn't fix the issue then idk what else to do.
 
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EDIT: I ordered a new stop, plunger, sleeve, and coil while I was ordering some other stuff. Will update this weekend.
Well the drop bank is still messed up, but i'm ordering new coil, sleeves, stops, and plungers for it and I will go from there.

EDIT: The bulbs started working again so not really sure what's up lol.
For some reason the bulbs that weren't working are now working so no clue on that!

EDIT: The nut that holds the crane to the shaft broke a weld so I will be pulling it completely apart and take welding the nut back on.
The crane isn't leaning back like it's supposed to, but keeps leaning forward which makes the ball fall out of it!
 
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Did you change the spring that drops the targets? Perhaps the new one is too resistant to allow the coil to reset the targets properly? Also make sure that coil is aligned perfectly and that there is no slop allowing the coil to shift under torque when pulsed. I have seen target banks reset perfectly by hand but when power is applied and the playfield is down the coil shifts slightly under power and makes the plunger bind against the sleeve.
 
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