An intermittent issue has started to happen more frequently as of late. When the machine is supposed to activate the outhole ejector and kick a ball to the shooter lane, it sometimes instead activates the knocker. This only happens sometimes, but as I said, it is getting more frequent.

I put the machine in single solenoid test mode, and the outhole ejector seems to work fine then. However, when in play mode, about 50% of the time, the ball does not kick out, and the knocker sounds instead.

What should I look for here? Thanks in advance!

Playing and searching around a bit with it, and I think it is an issue with the solenoid expander relay. Both the outhole ejector and the knocker have the same output wire, so I think that if the relay is not in the right position, the knocker will fire instead of the outhole ejector.

(This is where I should mention that this is all new to me. I just did some reading up and looking at schematics. So, if I misstate something or say something completely wrong, have mercy.)

The relay has a 555 bulb powering it. I read about a test where you put the pin in all lamp test mode. The lamp should blink on and off and the relay should click. My lamp seemed to stay on, and the relay only clicked some of the time. Other times, it was silent or perhaps had a very faint buzz.

I replaced the 555 bulb just in case and started a new game. The same thing happened when the game tried to kick out the ball into the shooter. Finally, after a few tries, it kicked out the ball correctly, and the game played perfectly. I tried several games and it played well. I then decided to do the all lamp test again. Same results as before. I then started a new game, and the ball would not kick out -- just the knocker again. Once the ball finally kicked out after several tries, the game played ok. I did the lamp test one final time, and this time had all clicks, no silence or buzz. I started a game, and it played well.

I hope this makes sense. I am guessing if you are familiar with solenoid expander relays on old Ballys, you will know what I am talking about.

At this point, I guess I should just watch the game and see if it continues to recur. Assuming it does, what are my next steps? I read an article that sounds like it could be any number of problems with the relay. Is there any way to figure this out and narrow down the possibilities?

I've only been playing Special Force intermittently, but honestly, I completely forgot about this post and the problem. I believe it resolved itself . . . or at least has temporarily. If it reoccurs, I'll have to dig in deeper.

This problem is reoccurring. I can solder wires together but don't think my skills are sufficient to deal with cracked solder points on a board. Should I just try to get a new expander? Would that be the next step, or is there something else I should try first?

Ok. Will do as soon as I get a chance. I'll report back. Thanks.

Well, that didn't take long. The back was filthy. I cleaned it with a paper towel so you could see the joints. If you don't think you can see them clearly, let me know. I took a bunch of bad iPhone pics, but I think you can probably see enough. I didn't see any cracks. What do you think?

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Bump for some feedback on my pictures. I have a couple weeks off work and plan to try to get this resolved if I can. Thanks!

Cool. Mine was a faulty relay. Marco Specialities finally had some replacement boards in stock and buying another solved my problem.

Now that I have a new one that works, I'm going to try repairing the old board. I don't have any experience with board repair so I was reluctant to try until I got a new one in case I made things worse. Now, I can freely make mistakes and learn from them.

Here. Check out this thread. It has the part numbers in it.

https://pinside.com/pinball/forum/topic/bally-special-force-solenoid-expander-board#post-1998757

I was able to fix the old board. It was just cold solder joints, and it was easier than I expected—without having much experience—to reflow the solder. That fixed it.

SF was my first pin as well. It is good to learn on, not too expensive, and pretty fun to play.

Look into getting an NVRAM chip rather than a remote battery holder. You’ll never have to worry about batteries again.

It’s a matter of preference but I really like incandescents on this pin. The attract mode is beautiful, and I’m not sure LEDs would do it justice.

Get the Demo Man.

It’s a better pin, and it will be easier to sell if and when you want to change things up.