Hi all,
I have a Stern BDK that I am almost done putting back together. (Just picked it up and did a complete teardown).
I am having some issues with the autoplunger. Sometimes it is very weak. As in too weak to launch a ball out of the shooter lane. Other times it is plenty strong as it gets the ball to the rollover lanes. And still other times, it is somewhere in between, it is strong enough to get the ball out of the shooter lane but not strong enough to get it to the rollovers.

The switch in the ball shooter lane "seems" to be good. I tried it in switch test and it seemed to be perfect. (I seem to recall that a flaky ball shooter lane switch could cause this)

An example of what might happen is...
To start a 3 ball multiball a ball will eject. The autoplunger strikes it and then another ball ejects. Well the ball that was autoplunged didn't make it out of the shooter lane and then comes rolling back. The autoplunger now has two balls to strike. On the second or third try it will get both balls out.
The autoplunger also seems to move without any hangups.
I did have to replace a switch in the ball trough. The other ones seem ok. (Not sure how these would matter with this issue)

Any ideas? Mechanical? Electrical? I didn't replace the coil as I don't have that size on hand (Plus in my experience a coil going bad is exceedingly rare. I have other coils I can try but I can't recall the coil rules on deciphering the numbers so I'd want to replace it with something close. (This coil is a 24-940) I still need to change the sleeve on it though. I don't think it would be the sleeve as I would think a gummed up sleeve would make it always weak. (Maybe I am wrong here)

Thanks.

I replaced the sleeve and cleaned the plunger this morning . The assembly seems to move smoothly. I did notice that the bracket was a little bent. Not normal bent. That was, some bozo with big pliers bent.

It got a little better.

Then I was looking at the manual to get a part number of the coil bracket. Then I noticed that the coil in the manual is different than the one in the game.. So, I guess I shouldn't be surprised.....luckily the one in the manual is one I have a spare of.

Manual shows 23-800, the machine has 24-940.

Thanks Lloyd.

Thanks Lloyd.