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Weak Flippers - what else can I check?

MarkS

MarkS

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10 Years
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Oct 14, 2013
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Devon
My recently acquired Surf'n Safari (Gottlieb System 3) has weak flippers. The LH one feels about 80% and can make the RH ramp, but the RH flipper feels about 50% and can't make the LH ramp (table set to 6.5 degrees). So I have concentrated first on the RH one:

First I checked the coils and they are the right ones according to the manual. The plunger seemed to move freely inside the sleeve but I took it apart to check anyway - apart from it all being a bit sooty the coil stop looks pretty flat and plunger doesn't look mushroomed. The coil sleeve has a tiny bit missing off the end (nearest the spring so the plunger is always past it) and isn't misshapen. I cleaned them up but that didn't seem to make any diffference.

Finally I checked the EOS switches which looked a bit mucky/corroded and were quite far apart with the plunger in - I tried sanding the switches and wiping with cardboard and narrowed the gap to about 1mm. Again it doesn't seem any better :(

Is there anything else I can do? I'd like to understand why it's weak rather than just blindly try a mini rebuild kit - especially if that wouldn't fix it if there's a different issue... any ideas please?

PS. The RH flipper shaft is slightly out of line due to grub screw wear - I assume I can file the shaft to fix this but this wouldn't affect its strength?
 
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Anyone got any ideas on this please? :hmm: Or do I just do a mini rebuild and hope?
 
Check everything in the path cleaning/filing switches, i.e. EOS switches, flipper buttons, check all plugs for burns/aging/desoldering, flipper enable relay. Rebuild may help if the coil stops are shot or the bushings are binding. If the plugers move freely it may make them more precise but probably not stronger.
 
I would just do a rebuild. It might have the wrong linkages from another game in there (as I discovered on a TAF that was supposedly restored)
 
Hmmm, thanks for the replies, sounds like I should just try a rebuild then... will update after I've tried that!
 
Not on expert on these - well in fact I can not stand them!
But have you done ground mods? I know this is not such a big thing on System 3 but it is worth a go.
I would be changing all the switches, EOS switches - but make sure you get the right type.
Also clean the relay that energizes the flippers.
Change sleeves, plungers and stops.
 
Hello, Mark,

The thing with 'conventional' flipper circuits, as I call the older non 'Fliptronic' type, is that the entire current drawn by the coil has to pass through the coil, End of Stroke switch, button switch and relay contacts, and the wiring between all of these. Any of those points giving poor contact can affect the flipper. It's not a case of a more dependable transistor switching the coil under processor control, with the button requesting flipper operation and the EoS saying it's worked.

In a way, this is a final left-over from the electro-mechanical days; a solenoid operates through a series of contacts, distributed around a good part of, if not the entire machine.

A T2 (one of Williams final pre-fliptronic games) was discussed here quite recently, with its flippers not quite up to standard, and the vendor advised its new owner to sand the EoS switches (again, as it turned out). They chose to change the flipper units entirely, since the coils were wrong in any case. As above, filing the contacts is better, though if they're really badly worn you may be better replacing them. Are there capacitors on the EoS switches? And probably the buttons as well, though ipdb entries for this era of Gottlieb games don't have many pictures of the mechanics (and forget having a look at the manual). Without capacitors fitted, the EoS contacts can burn quickly. By this time, they'd probably be due for replacement anyway.
 
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I've attached a couple of photos below which hopefully shows the mechanics - these are of the RH flipper, the weaker one. (Ironically the LH one that works better has a detached wire on the capacitor and the coil stop is screwed in at an angle but tight.)

I don't understand what the capacitor does here?

Pick Holder said:
But have you done ground mods? I know this is not such a big thing on System 3 but it is worth a go.

Also clean the relay that energizes the flippers.
Click to expand...

Eeek, sorry but I don't know what either of these mean? Are these something to do with the boards?

On the one hand I think just do a rebuild, but if it's all moving freely I'd like to understand better what else could be a cause if that's possible - or is that a waste of time? :)
 

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Not the best photo, is this considered worn? :hmm: Sorry, I'm new to this :)

1722856293347.png
 
MarkS said:
I don't understand what the capacitor does here?
Click to expand...

Hello,

The capacitor connected across the EoS switch helps to supress a damaging spark as the switch opens - turning off (or turning down)* the power winding produces a large voltage as the magnetic field decreases. Without the capacitor this would jump across the opening contacts, the capacitor serves to absorb it until the contacts are too far apart for that. It's much the same as the old-fashioned 'points and condenser' set-up in a petrol engine distributor, condenser being another term for capacitor.

Gottlieb solid-state games used to have a tendency to poor earthing, hence popular modifications to improve it.

A flipper (enable) relay breaks the return circuit of the flippers when it's not energised, such as when in attract mode or if the game's tilted. With it energised, the only remaining break in the returns are the flipper buttons, so pressing them allows current to flow. Most electronic pins have a pcb-mounted relay, with a sealed plastic case, but Gottlieb persisted with e/m type relays ('Game Over' and 'Tilt'), using slotted frames moving bladed contacts.

Yes, the plunger and end stop shown do look worn. I think I see filing marks on the end stop, where it's been rescued once already. And the EoS shows the whitish burn marks resulting from a failed capacitor.

* after studying the pictures in this thread, I conclude that Gottlieb were still using serial-wound flipper coils; with these, the EoS switch brings the hold winding into circuit, rather than cutting the power winding out of circuit
 
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Thanks for the further replies, it's slowly starting to make more sense!

I see a full rebuild kit on pbresource.com:


Does anyone know if there is a better/UK/cheaper source for these kits? Pinball Mania only has the mini kit.
 
Looking at your pictures again, in the second picture of the group of three (No. 3165) the solenoid plunger doesn't seem to be straight*, as in properly lined up to slide into the coil. That could be costing some power, as it would need to straighten up as the coil pulls in. I'm not that familiar with this design of flipper unit, but it seems to have a similar 'coil stop' bracket at each end - could there be a missing stop on that end (not according to the drawing from PBR), allowing an excessive travel, which lets (or forces) the plunger out of line? Or a lack of movement (rotationally) between the plunger, the link pinned into it, and the 'crank' or 'pawl' fitted onto the flipper shaft?

* though the playfield is upright in the picture. You mentioned at first that the coil sleeve has a bite out of the end; this may be a cause or a symptom of the plunger mis-alignment. If it'll push out of the coil, move the damaged section elsewhere, or replace the sleeve.
 
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Hmmm I see what you mean about the plunger angle... I will need to take another look. The sleeve comes out of the coil easily and the plunger feels smooth in/out the sleeve, however I do recall there being quite a bit of play in link mechanism area so I will have to check that again too (not home right now). Photos of the sleeve and coil:
 

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Rebuild the linkages with a full PBR kit and be done with it.
You'll get hit with parcelfarce's charge irrespective of value so why not? You'll also have to pay vat on the parts. However, I think Steve gives 10% off if you spend over a hundred dollars so make the order up with some other goodies to get some sort of value out of it.
 
If you'll be sending off to usa-land, maybe add flipper button switches too, if you feel like adding on to your order. As I see it, the flipper assemblies are pretty worn in any case, and need significant work. If they've got to that state, check on the button switches (and relay contacts, too) before ordering; it would be galling to have to put in another request. The EoS switches suffer the most, button contacts fare a little better, while tbf the relay contacts are the last point before ground and often escape much damage - I think the relay only operates at the beginning and end of a game, so unless some clueless sort is thrashing away on the buttons as it does there's less chance of the contacts actually carrying current as they open.
 
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Thanks for mentioning the flipper button switches, I hadn't even thought to look at those... the RH button switch looks older/different from the LH one and the switch leaves were far apart - I have closed the gap and sanded the contacts and it's improved it a little, even made it up the ramp a couple of times so that's another area causing an issue! I also re-checked the plunger into the flipper coil and yes the plunger does have quite a bit of play in it from the linkage area although it goes in smoothly. I am going to do a complete rebuild but it's been very helpful to understand what issues there can be 👍

Jay Walker said:
tbf the relay contacts are the last point before ground and often escape much damage - I think the relay only operates at the beginning and end of a game, so unless some clueless sort is thrashing away on the buttons as it does there's less chance of the contacts actually carrying current as they open.
Click to expand...

I have tried googling this and get mostly EM articles/threads, I don't really understand the relay contacts other than it says Gottliebs used them for most things and to check they are clean.... does anyone has a link showing where to find them please? Are they on a board? :hmm:
 
Hello,

The relays (which I think are called Game Over, designated Q and Tilt, T,) aren't on a circuit board; they're most likely to be under the playfield or in the cabinet. A small mounting frame, with a tiny coil, armature and plate with slots in, which opens/closes the contacts. Probably mounted on a bit of metal rail. If you're getting pictures of e/m games, similar to the relays operating bumpers or score reels.

The ipdb entries for this age of Gottlieb games are light on interior pictures, but Class of 1812 and Operation Thunder have some. The C 1812 is appallingly dusty inside, but it and OT both seem to have the relays on the floor of the cabinet, to the right, behind the transformer/rectifier/fuse assembly. A plastic cover is shown with OT, but not C 1812. Cue Ball Wizard CBW also shows a cover over the transformer, and what I take to be Gottlieb's offering for a light box bolt in its cashbox.
 
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So I grabbed a couple of coil sleeves from @David retro at Pinfest as that was an easy thing to try out before I ordered the whole kit to rebuild both flippers, to see what difference that could make. I replaced the sleeves on both flippers and also wedged in (semi-temporary "fix"!) the RH coil which was slightly wobbly... the result was that the RH flipper is now strong enough to make the ramp ~80% of the time, but weirdly the LH flipper is now weaker! Either way I will get the rebuild kit to re-do both flippers but it's interesting to see how easily they are affected by each component, especially what seems minor to me in a tiny nick off a sleeve and a slight wobble on the coil.

I do now have a couple of follow-up queries which might help me (and anyone else reading this thread in future) understand this stuff better if anyone can help please:

1. The LH flipper hums now when it is held up, I'm sure it didn't do this before and the RH flipper doesn't do this. It seems to get louder the longer it's held up? Google reveals answers varying from "it's Stern's fault" to filing the plunger tip, refitting the coil stop, replacing the EOS switches and alien invasion. All seem viable to me, but which is most likely?

2. Ummmm, are the EOS switches supposed to spark?! :-o I've never looked before but hadn't really expected that, not being very electrically-minded I don't really understand what that indicates other than not to leave the gas on? 💥
 
1. Normal, as the coil heats up hum may change. Tight mounting of all parts counters it somewhat.
2. There should be a capacitor across the EOS (the yellow thing) to suppress the spark mostly. This sparking is the reason the contacts burn up and need to be cleaned, the right EOS switch for your application has contacts enabling that. New style EOS for electronic flippers don't and therefore can't be used - buy the right rebuild kit.
 
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