Thanks for that

You're welcome. MG Chemicals Superwick has given me the best results. I bought some no-name stuff for less, but it was oxidized and wouldn't absorb any solder. I like the wider widths (MG Blue or Yellow) for those big globs on solenoid tabs.

Yes! It is totally worth buying the quality solder wick. Comes in handy for board work too in addition to a good desoldering station.

I still have the flipper flutter after rejoining the lugs on the solenoid and the one of the wires on the switch. My first soldering job.

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This might be of interest: https://pinside.com/pinball/forum/topic/flipper-flutter-problem-bally-1981

Flutter/machine gun: I tried sanding the EOS switch contacts but it didn’t change. I took the readings in the pic. Do they rule anything in or out. I didn’t test the flipper button switch, since it seems to me that the issue is not the initial up, it is that something is forgetting to tell the flipper to *stay* up (so machine gun fires the flipper back up every time it comes back down) which I thought was the EOS switch. Also the EOS switch has heavy sparking between the contacts during the machine gun.

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Fluttering is caused by an open circuit in the "hold" winding on the flipper coil.
The flipper coil has two windings, one powerful to thrust the flipper, the other low power to hold the flipper up.

At idle, the EOS switch is closed which shorts out the hold (thin wire) winding on the flipper coil.
Player presses the flipper button, which causes full 43 volts to go through the thrust (thick wire) winding on the flipper coil.
The flipper reaches the end of the stroke and opens the EOS switch.
Opening the EOS switch now puts the hold winding in series with the thrust winding to hold the flipper in the up position with reduced power to prevent burnout.

However in your case the hold winding is open circuit so when the EOS switch opens, current through the total flipper coils collapses so the flipper falls back.
When it falls back enough it closes the EOS switch, which now re-energizes the thrust winding. After the EOS switch opens again the open circuit hold winding fails to hold the flipper in the up position and the flipper falls back again - rinse and repeat.

With the machine OFF, put a piece of paper between the EOS switch so it no longer makes contact and measure the resistance across the two yellow wires on the flipper coil lugs. You should measure around 320 ohms.

Thanks very much! This will be really helpful

Flutter/machine gun: with the paper: the only connection showing Omhs is in the pic (3.5 on the first part of the omhs reader setting) the rest are showing 0. I also got better pics of the contacts on the switch.

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Holy crap, I though EM schematics were crazy, but now looking at the schematic for F2K I’m cracking up. I thought I would check and see if there are particular transistors to check, but I’m not sure I’ve found all the flipper switch sections!

Transistors don't drive the flippers on these games.

When you say the rest showed 0, do you mean the meter reading didn't change when you connected the meter probes or the meter reading changed to zero when you applied the meter probes (i.e. just like when you touch both meter leads together as a short circuit)?

Is your multi-meter auto-ranging or do you need to set the range you're measuring? i.e. if you have multiple ohms ranges like 200, 2k, 20k, 200k, 2M you need to select 2k ohms range to check the hold winding resistance.

See the image below with the thin hold winding wires highlighted. Very gently prod those wires to see if any are loose/broken. They sometimes break at the point of connecting to the lug.

Flipper_Windngs1.jpg

I think the thin wire is not fully connected, I can unwind one loop and reattached to lug and cut off excess, right? I notice a couple screws holding the bracket has fallen off, so I’m sure that the whole assembly was rattling around a lot.

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Before you solder a new section of the coil wire you need to sand it to remove the varnish that it is coated with. Solder won't stick to it otherwise

Awesome thanks

Didn’t seem to work. And correct reading of the lugs is : 1(thick) - 2(thick) - 3(thin) is:

1-2 = 0 (meaning it starts at 1 and goes to 0)

Everything else is “negative” meaning it starts at 1 and doesn’t move.

This is at 200k setting.

Anyone know what this means and/or how I can rule out the diodes? Thanks.

Assuming diodes are relevant, which I thought from other posts might be....

Just a detail. If by "a couple screws holding the bracket have fallen off" you mean there are 2 empty holes in the copper coil stop, that's normal. No sweat.

Thanks clodpole. It was the other screws into the underside of the play field. See pic.

Here is my markup of the schematic. Is this right? I forgot to check the other flipper, which is working, to see if the multimeter readings are different.

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The diodes on your flipper coil are installed backwards in reference to the schematics, however the wires and EOS switch have been alternatively connected on the coil to compensate. Your connections as-is will work but they don't 100% match the schematics.

To measure the resistance of the two windings on the flipper coil, you must open the EOS switch (put a piace of paper between the contacts).
Set the multi-meter to "200" ohms range.
Put either meter lead on the middle yellow coil lug and the other meter lead on the other side lug with the green wire.
You should measure around 4 ohms.

Now set your multi-meter to "2k" or "2000" ohms range however your meter is marked.
Put either meter lead on the middle yellow coil lug and the other meter lead on the side lug with blue-white and yellow wires.
You should measure around 320 ohms. If the meter reading doesn't change when you put the probes on the lugs then the hold winding on the coil is open circuit. If you can't find the break in the thin winding wire then you might need to get replacement coils. As mentioned that wire usually breaks next to either lug it's soldered to.
The thin winding wire is the orange coil wire winding as shown below. The left side is the schematic for your setup, the right side represents your coil wiring.

Flipper_Coil.gif

Thanks quench for the image, I did not realize that there should be a thin wire going to the middle lug too. If I looked more closely / attentively to your prior photo I would have seen it. Thanks again. I will check the machine again, as I think that might be my issue, because I do not recall seeing the thin wire also attached to the middle lug

I get it - you replaced those 2 screws holding the bracket onto the plywood?

Yes it was the screws holding the bracket into the plywood

Looks like I’ll just have to replace the coil. I couldn’t find the end that would go to the middle lug, and when I was looking around for it I severed the thin wire somewhere. I did resolder the thin wire after severing it. But I still have the machine gun effect. If I put an old em gottlieb flipper coil it won’t ruin anything right?

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So to confirm, you do not measure 320 ohms resistance across the two lugs with the thin wire? Sounds like you need a new coil.

Don't do it, EM flipper coil is not appropriate for this application and will likely cause other damage .

Correct on the ohms. It just stays at 1.

Flight on Flight.

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"Me Gorgar; me want beer!"

Hardware geek question:

F2K has 6 kickers (4 to play tennis and 2 in the ball walk maze). Each has a 3-piece kicker assembly held together by one "e" clip and one cotter pin. The part which attaches to the plywood fits over a pin sticking out one side of the kicker itself, and the plunger link fits over a pin on the opposite side of the kicker. That is, all but the lower left kicker assembly (just above the left flipper) on which both pins stick up on the same side of the metal kicker (see photo).

Do you know why?

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The kicker and the bracket only go together one way. For the plunger, look and see how it lines up the best with the coli sleeve. Put it on the side of the kicker that makes a straight run to the sleeve.

I see what you mean re the kicker and that is interesting. The part the plunger link gets e-clipped on is installed through the opposite side of the bracket than a typical one. I have a fully populated pf in the shop and all kickers are made the same way.

Weird, huh? It fits, and works, but it was manufactured and installed defferently than the others.

Another thing is that these wear out and no replacement available. The hole on the arm eggs out and creates a lot of slop.

https://www.pinballlife.com/slingshotballshooter-plunger-and-link-2-plunger.html

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https://www.pinballlife.com/slingshotballshooter-plunger-and-link-2-18-plunger.html

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Or if you really want to step it up, PBR has some NOS Stern slingshot links. He is fairly proud of them at $1.94 each.

http://www.pbresource.com/special.html

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https://www.marcospecialties.com/pinball-parts/03-8085

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Or if you are talking about the pivot hole on the pivot bracket, it is being looked into about trying to get new sling shot levers reproduced.

Thanks for posting these but I should have been more clear, I was referring to the arm A-157-1 and the pivot A-143. I'm not sure which part wears out more but there will be a lot of side to side motion (slop) when severely worn.

I did a mod on kicker assemblies.
1) File down the round housing to take a flat washer.
2) Epoxy the washer to the kicker housing.
3) Reassemble kicker and fulcrum bracket.
This process helped keep the kicker assembly more or less vertical.

The arm is the most serious wear part. I reused the pivot when I replaced the ones on meteor with the nos ones and the slop was gone.

My slop issues are related to the pivot point on the bracket being worn. My kicker arms show very little wear.

Pinball life sells this pivot bracket that will work on your Sterns. The pivot is shorter than original so you must file off about .030" of material on the pivot hole on the kicker. Also, this bracket is not as deep as the original so you have to grind out the inside screw hole to allow for clearance the original kicker lever.

https://www.pinballlife.com/search.html?Search=slingshot

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Your kicker arms aren't egged out in the hole? Consider yourself lucky to have the opposite problem than most have!

I didn't think it would make that much of a difference but boy did it once I put the new ones on. Now I automatically do this on all games, stern or not, if there's any rocking side to side.

Thanks for letting me know not to swap in EM flipper coils , but how about from an SS Bally. They are 25-500 / 28-1000. The one I took out is 25-600 / 34-4500. Is that going to mess anything up? Thanks

The power winding is fine at 25-500 although would be a little stronger than a stern coil. The hold winding at only 1000 turns is wildly inappropriately strong, and would likely blow the solenoid fuse.

Of course, likely you'd have to add diodes as well, unless the coil came from a DC EM.

Yes I was given diodes to install on the coil as well, will that prevent The solenoid fuse from blowing out? I don’t want to create more problems, because the machine still plays alright even with the machine gunning flipper.

No, the diodes are there to prevent back EMF through the computer boards.

Any particular reason you can't just order the correct coil? They aren't rare.

Yes. A new coil costs something like 10 dollars.

I am new to pinball and have not needed to order anything online outside of Amazon in years, so I guess I just wanted to buy something face to face rather than order online from somewhere I’m not familiar with. But since I hear Marco mentioned so much, I guess I should just get over it and order what I need from there.

I did install the Bally and it stopped the machine gunning, and haven’t blown a fuse after about ten three-ball games. But still the coil definitely doesn’t sit as tightly in the assembly as there is some loose space between the coil stop and the coil, so I am going to order the proper coils.

I am also going to go back to earlier in the thread because someone mentioned that the diodes appeared to have been installed backwards from what the schematic said, and I went ahead and installed the diodes the same way they were. So I can make sure to install them correctly when I get the correct coils.

BTW, why are the Bally’s hold winding so strong compared to the Stern?

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I am new to pinball and have not needed to order anything online outside of Amazon in years, so I guess I just wanted to buy something face to face rather than order online from somewhere I’m not familiar with. But since I hear Marco mentioned so much, I guess I should just get over it and order what I need from there.

I did install the Bally and it stopped the machine gunning, and haven’t blown a fuse after about ten three-ball games. But still the coil definitely doesn’t sit as tightly in the assembly as there is some loose space between the coil stop and the coil, so I am going to order the proper coils.

I am also going to go back to earlier in the thread because someone mentioned that the diodes appeared to have been installed backwards from what the schematic said, and I went ahead and installed the diodes the same way they were. So I can make sure to install them correctly when I get the correct coils.

BTW, why are the Bally’s hold winding so strong compared to the Stern?

That is not a flipper coil from a Bally SS, it's from a Bally EM.

The hold windings are the same, you're comparing the wrong coils.

The new coils usually come with diodes pre-installed and also come with a new sleeve. I don't remember for sure but there should also be a spring washer installed between the coil and coil bracket.

If it was an AC flipper coil, it needs to be strong enough to hold through the period of time that the AC sine wave passes the zero point - no power on the coil at that moment. It's why there is a slight magnetism in AC coil stops, the magnetism helps hold the flipper up continuously. It's why AC flipper coils buzz, as well.

Pinball machines need parts periodically. Do yourself a favor and obtain the correct parts where needed; other than tools I don't see Amazon really being a valid supplier of that. I've ordered somethings like cleaning supplies (wax) and in a pinch I got some capacitors/resistors from there (jury is out if the cheapie caps will prove to be any good over the long haul) - but other things if listed are likely to either be wildly overpriced or just not the right thing.

2 weeks later... You'll recall I was going to replace the 1000uF capacitor at C7 on my SB-300 sound board with a 4700uF/35v capacitor, on the theory that it would eliminate the loud belch my machine makes on power up. Today I got the new cap installed, and the belch is still present, a smidge louder and its timbre has changed from true belch to more of a pure tone.

Oh well, I guess I just have to live with the big burp.

Note: OEM Bally bobbins are slightly shorter than repro bobbins.
------ hence they use the spring washer.