The only thing that strikes more fear into a new pinball owner's heart than setting the EOS Gap is rebuilding their Pop Bumpers.

There are always posts about how hard it is, but it really isn't hard at all. Like most complex tasks, rebuilding pops is quite easy, if you break it down into small steps.

A good machine needs strong Pops for fast action.

I know I've been many months late getting this guide done, but I'm fixing machines damaged by Hurricane Sandy and finally have some time to kill in my hotel.

First label your wires. I know you can look it up in the manual, or even remember the wiring, but sometimes you get back to things much later than you think you will. Nobody ever complained that they took too many pictures or labeled everything too well.

Next unsolder the coil wires at the top of the bracket, and the lamp wires on the underside of the playfield.

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Next pull the staples that hold down the Lamp leads.

You can put a sharp Scratch Awl under the staples and give them a light tap. Pull the staples out completely with a pair of pliers.

If you don't have a pneumatic staple gun to put new staples in, carefully lift the staples just enough to pull the leads through. Then when you put everything back together, pass the leads under the staples, and tap the staples back down securely.

If the staple breaks, be careful to pull out any remnants.

There is usually a little piece of rubber or vinyl insulation that keeps the lamp from shorting against the bracket. You can reuse this, or use a piece of shrink tubing or even aquarium air line.

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Next remove the two 5/16" nuts (yellow handled nut wrench if you have a mechanic's set) that hold the Ring.

Be ready to catch the ring if you have the playfield upsidedown on a rotisserie, as it will drop away freely. Don't lose the two small washers that are on the underside of the Metal Yoke.

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Here is the Ring, washers and nuts.

Can you tell what side of the ring the balls always hit on this particular game?

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Brand new Rings are not ready for installation right out of the box.

New Rings have a rough sandpaper surface that quickly chews up your balls.

1. Sand out any scratches to 500 or 600 grit.

2. Polish with Green Compound to produce a mirror finish

3. Polish the shafts too for ultra fast action.

4. Wax the Rings and shafts.

5. Install.

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Some Ring/Rod porn for you:

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Next remove the three 5/16" nuts from the Bracket.

If the whole screw shaft is turning freely in the wood, grab the shaft with Vise-Grips and turn the nut with an open ended wrench. Make note to fill hole with wood epoxy, redrill and pound in a new "Fin Shank Screw" - the fancy name for those screws.

http://www.pinballlife.com/index.php?p=product&id=240

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The whole Bracket lifts off and you can see the Spoon, the Switch Stack and the Lamp leads.

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From the topside of the playfield, remove the Pop Bumper Cap and remove the two screws at the bottom of the Pop Body.

Gently lift the whole assembly out, don't scratch the playfield with the Lamp leads.

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Now that you have it out, it does not look that complicated, does it?

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Now, let's start the rebuild.

Unless you want the look of yellowed plastic (don't laugh, on older games it often looks best), I'm assuming most of these parts are going to be brand new. They are very inexpensive, so replace them if at all possible.

First, put down the new Base into the Pop Bumper hole in the playfield.

Rotate the Base so the large base holes line up with the playfield screw holes.

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Next install the Skirt Spring, also referred to as the "Small Spring".

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Place the Skirt on the Spring.

Note the the two widely spaced holes go over the large holes in the playfield. You can't really mess this up once you look at it. The Ring rods travel through those holes.

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Next the Body snaps into the Base.

Note how the larger holes line up with the screw holes and not the Lamp lead holes. Again, you are not going to mess this up, but watch for it.

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Here we slide in the Lamp holder through the small Lamp lead holes.

Push it all the way to the bottom.

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If you somehow got stuck with the flexible wire lead Lamp Holders, you have now probably discovered that they won't go down very far into the Body, and tend to fall to one side or another.

You need to fix this with a Zip-tie so the Holder can go all the way down to the bottom of the body.

Next time, make sure you buy the stiff wire leads, LOL.

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Next you can install the bulb.

If you are using a LED Lamp, don't put the bulb in yet, as you may have to reverse the bulb to get the polarity right (depending on the game).

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The cap goes on with two screws.

Again, don't put the cap on yet if you are using LEDs. Once you have the game powered up, THEN you will find if the bulb needs reversing (literally pull it out and replace it 180°).

NOTE: Many System3-7 game where the pop bumper lamps are under CPU control (meaning that they are NOT part of the GI lighting circuit (on all the time)) won't light up simple, single LEDs. You will need more complex LEDs with multiple lamps because they have the little, on board regulator in the base. If you used 555 sockets, you can try reversing the bulb 180*, but the #44 sockets require a better bulb.

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Now that the topside of the bumper is completed, we go under the playfield to the Bracket assembly.

First, take a look at the Coil and see if it is the correct model for your game (usually the required coils are listed on the inside cover of the manual).

Don't be surprised if you have a smorgasbord of mismatched coils, as most operators only cared about keeping the game working, not how well it played.

Take the two screws off the back of the bracket and the whole assembly will come apart.

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Now that you have the Bracket apart, inspect the Plunger for wear. If it's not smooth and shiny, replace it. If the end is mushroomed, replace the Plunger and the Bracket; as it's probably too worn to fool with. If the Plunger has become magnetized and is covered with metal shavings, replace it.

Clean any parts you are keeping with Fantastik or any other degreaser using an old toothbrush. Clean inside the Coil too.

Replace the Sleeve. If it's stuck tight in the coil, press the protruding part down flat on your workbench and push it out. If it is hopelessly stuck, replace the coil (it probably overheated at some point, and could be a liability latter on). Remember that the lip on the Sleeve goes on the diode end of the coil.

The Bracket has 2 yokes. The metal one is almost always broken, the fiber one is always worn. Always replace them both.

Make sure both screws are the type with lock washers installed on them. If the Yoke Retaining Bracket comes loose, the Plunger will become damaged.

When reassembling the Bracket, remember to press the Yoke Retaining Bracket towards the Coil Stop end of the Bracket as you tighten the screws. By doing this you will ensure that there is no slop in the Coil; and thus all the energy will be transmitted to the ball. The Coil should NOT be loose or have any play.

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The plastic Spoon on the front of the Switch Stack should be replaced.

Often the ball will hit the bumpers from one direction and the inside spoon surface will wear in a pattern, or even a straight groove.

The Switch Stack has some room for adjustment so that the center of the Spoon can be directly over the center of the Skirt Pin. Loosen the two screws a bit so you can just move the Switch around.

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Many spoons are translucent plastic, assuming yours are, you can use the following operator's trick:

Use a strong beam of light to illuminate the underside of the spoon.

Look at the shadow cast by the contact point between the Skirt Pin and the Spoon.

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Move the Switch Stack around until the Skirt Pin is exactly in the center of the spoon.

Check your work by tapping your finger in the center of the Spoon. If the Skirt Pin is truly centered, there will be no play or movement. If not centered, you will notice the Pin will slightly veer off to one side as you tap. Purposely misaligned the Spoon to learn this effect.

If you spoon is black or an opaque plastic, use the tapping technique as above.

Tighten the screws on the Switch Stack and double check that your Pin is still in the center of the Spoon.

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Once the Spoon is centered, put your now reassembled Coil Bracket back into place.

Resolder your Lamp leads and the Coil leads.

Clean the switch contacts with a crisp dollar bill. Gently press the contacts together while pulling the bill between them, repeat until bill comes out clean.

Here is a picture to explain how all of the parts fit back together around the Switch Stack.

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When the Pop Bumper is at rest, we want the Solenoid Switch to have a very small gap so that the Bumper has a "hair trigger" (this reference comes from fire arms, where a small amount of force (I guess a human hair) can set off the firing pin).

On a pinball game, we want the slightest amount of force to trigger the bumpers so they are VERY lively.

When the game is powered on, pound on the playfield a few times and make sure that the Pop Bumpers do not activate from vibration alone.

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The Scoring Switch activates whenever the Pop Bumper fires. The Solenoid drives the Fiber Yoke into closing the Scoring Switch.

The Gap on the Scoring Switch is not very critical. As long as the contacts touch before the last 1/8" of travel it should be fine. This last bit of travel lets the contacts slide across each other for self cleaning action.

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So that's it. Like always, I'll fix any typos over the next few days.

Once you have done it, figure about 10 minutes per bumper to rebuild them.

Again, most of these parts are very inexpensive, so don't waste time cleaning or filing old ones.

Newer Bumper Bodies are much less translucent that the old ones, so a 5 LED lamp may be needed to illuminate as well as the old incandescent 555 did.

Check your voltage at the coils to make sure you are getting all the juice they need.

I assume you checked that the correct coils were installed for your game.

I assume you checked that the plungers are moving freely.

I assume you set the Solenoid switches to the smallest gap possible.

If none of that helps, then you can always install more powerful coils. Don't go crazy with power, just swap out the next stronger value.

Indeed!

You'll be wrenching on pins like a pro in no time.

Yes. It will be a little bit of a wrestling match, but no big deal. Replace your Yokes at the same time, as I'm sure your metal one is broken by now.

Changed it, thanks!

I need to add a few more pics to the Flipper guide too and I can migrate them both over.

Yeah, I've done it on location plenty of times - not as fun as disconnecting a few cables and plopping it on the rotisserie, that's for sure.

Still breaking.

I always tell everyone I want to be displayed at this funeral home:

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If it is smooth and polishes up nice, then reuse it.

Look where the rod becomes threaded at the ends. If there is any cracking, replace it.

http://pinside.com/pinball/forum/topic/vids-guide-to-upgradingrebuilding-flippers

http://pinside.com/pinball/forum/topic/vids-quick-and-dirty-rotisserie-guide

http://pinside.com/pinball/forum/topic/vids-guide-to-lighted-flipper-buttons-for-418

http://pinside.com/pinball/forum/topic/vids-guide-to-proper-shipping-playfields

You probably don't have to remove more than 2 staples per bumper.

Unsolder the 2 legs of the lamp holder, not the entire lighting circuit.

If you have brand new replacement lamps, you can just cut the leads on the old one.

Then solder the new one into the "nest" of the old wires.

Don't use the prop rod, pull the whole playfield forward and lean it backwards against the back box (use a towel to keep it from getting scratched).

Your back will thank you.

Or just disconnect the plugs and pull the whole playfield out and lay it across 2 saw horses.

This might take you 4 minutes the first time, and 1 minute the next. Really easy, not scary at all.

If it has just the 2 hinges, then disconnect it and pull it out of the cab.

Once you try it, you will not believe that you ever thought about doing it any other way. No solder dripping into the machine and of course the fact that you can sit while you work.

Vid, you did not mention what you use to re-staple the light leads.

An upholstery stapler is good if you have an air compressor in the shop.

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This.

A new coil is $10, so if the wires look too damaged, don't hesitate to just replace it.

90% of the time, nail polish is fine.

A nice solution.

Usually I put in the body, then the ring.

Once in a while you find a body fatter than the ring, if that's the case, obviously the ring needs to go in first.

If you don't have a long nose pneumatic stapler in your shop, you can use your diags to lift one staple leg for lead removal, then tap it back down to secure the new leads.

I've done that when doing "on location" repairs.

The staples keep the leads from shorting against the pop bracket.

Great contribution and pics Ken.

Thank you!

Take the pop apart and see how it is different than the other 2.

It could be cracked, wrong spring, wrong wafer.......

Post pictures so we can see what is wrong.

Yep there is a longer ring and rod for a bunch of Gotlieb years.

Your easiest fix is probably to cut a Coupling Nut to the additional length and use a machine screw to fasten the yokes rather than the lock nut.

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Need a pic to know what you've got.

Firepower pop lamp wire colors:

Top Left pop = Red wire Yellow stripe and Yellow wire blue stripe
Top Right = Red/Grn Yel/Blu
Bottom Left = Red/Violet Yel/Blu
Bottom Right = Red/Blu Yel/Blu

The banded side of the diode goes to the red wires.

http://www.firepowerpinball.com/downloads/LampWiring.pdf

http://www.firepowerpinball.com/ is the greatest effort "fan site" for any pinball machine ever.

Excellent work.

Thin staples need a stapler made for them. So you would have to buy both thin staples AND a new stapler.

If you do lots of rebuilding get an pneumatic upholstery stapler, it has a nice long nose for extra reach.

That vinyl tubing can be replaced with aquarium airline tubing from Kmart or any pet store.

The factory is full of sloppy workmanship.

It is possible that a short tube got mixed in and installed.

The tubing **should** extend under the pop, but as long as it's secured against shorting out, it's fine.

It will be fine.

Again, smaller staples would require a different, smaller stapler.

Many of the original staples were plated with copper that supposedly kept the corrosion down and was easy on the stapler itself. I used to have a manual stapler that used them, but I'm not sure where it is now, or where I'd buy the staples.

Usually they lay to one side or the other, never straight up and centered.

I'd avoid them for pop use, unless you are on a service call and they are the only thing you have.

That is usually the little disc capacitor that is on the pop switch.

Cut one leg of the disc cap (NOT THE DIODE) and see if the problem is fixed. If it is, replace the cap (.047uf 50v non-polarized )

I don't think anyone sells a kit for specifically for CV.

If you call Terry at PL, I'm sure he can make one for you.

Probably because most pops are the same parts since the 70s, whereas flippers changed coil stops/springs/switches every few years.

Action Pinball sells the entire assembly for many old games, but most people don't need to replace everything.

http://www.actionpinball.com/pops.htm

I'd use the adhesive version, as like you have seen, the loose rings gather abrasive crud under them.

I like the sheet Mylar you cut yourself:

http://www.marcospecialties.com/pinball-parts/66-MFT

http://www.pinballcenter.eu/catalog/advanced_search_result.php?keywords=7443-5&ampx=0&ampy=0&ampsearch_in_description=1

You want the wires to be on the same terminal they were on before (banded or unbanded side of the diode) - otherwise you blow stuff up.

Sounds like your rods are worn out.

You can peen over the tops of the rods to try and firm them up, but for a few bucks, it's probably best to just replace them with new ones.

They are usually "riveted" by being peened over onto the ring.

They do wear out, either becoming loose, or the threaded end breaks off.

At $4, they are a normal wear-out kind of item that you just throw away.

If it was the last ring rod on earth you could try to peen it over again with a doming punch, or TIG weld it.

http://www.pinballlife.com/index.php?p=product&id=1518

This tool is not too durable, so use it gently, but it works great

First check your voltage across the coil.

You put the leaf into one of the slots and GENTLY bend it so you close the switch gap.

Lets see some CLEAR picture from a few angles - including the hole.

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When it came down to Solid State machines, Williams generally were better built vs. Bally.

You could name a ton of junky Bally features like those tiny .1" header pins on Bally boards (or just the thinner Bally boards themselves), the terrible linear flippers with their little nylon button that instantly wears out, the foil covered cardboard "ground plane" in the backbox, or the odd solenoid expander boards that stop working when a 555 bulb mounted next to them burns out.

But the one place that Bally totally trumped Williams was the serviceability of their pop bumpers. Most pop bumpers in the world require you to unsolder the lamp socket before you can perform routine servicing on them. Of course the lamp socket is buried and stapled as deeply into the underside of the playfield as you can get.

From 1981 to 1989 Bally had an ingenious solution, allowing the entire pop mech to be removable in once piece. No de-soldering, no un-stapling, even the switch gap can be set with the pop just sitting in front of you.

And, unlike Williams where you have to replace the entire frame and bracket when the coil stop wears, the Bally allows you to replace just the coil stop!

The system is so simple, it makes you want to rebuild your pop bumpers!

Above the playfield you have the Ring/Rod, Wafer (aka Skirt), and Small Spring.

These are all standard parts and can be freely interchanged with Williams pieces.

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Servicing the pop body could not be easier.

Remove 2 screws and pull straight up.

The 80s Bally pop bodies can take screw on pop caps, or caps that use the retention clips.

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On the bottom of the pop body, you can see the 2 male pins that provide power to the lamp socket.

Clean these with a brass brush until shiny.

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The base is where all the action is.

Note the female sockets for the lamp.

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7

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The Switch Stack is a crazy collection of different fiber spacers.

When servicing the spoon or switch leaves, don't take the stack apart further than you need to.

If you drop the stack, or indeed take the whole thing apart, refer to this picture to reassemble it correctly.

Note that some spacers are actually thicker than others....

Clean the switch contact faces by pulling a crisp $100 bill between them until the bill pulls out clean (without a black stripe from the contacts ).

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A standard Williams spoon is 1/10 the price of a genuine Bally replacement.

They are interchangeable, as long as you slightly enlarge the mounting holes.

Note here how the old spoon has grooves worn into it and needs to be replaced.

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Here you can see the difference between Williams and Bally Yokes.

Williams metal yokes are always broken when you take apart a pop bumper; Bally are much better designed with their reinforcing lip.

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Although they look different, the Williams and Bally Yokes are interchangeable.

Unless your Bally metal yoke is totally worn out, I'd keep it and just replace only the fiber yoke with a Williams one. The Bally metal yoke is much superior.

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As Bally parts are harder to find, people always ask if a Williams mech can be substituted for a Bally mech.

It can, but you have to drill out the mounting holes on the Williams bracket.

Also note that the Bally coils are 1/16" shorter than the Williams, so make sure you have the Bally coil mounted tight. Loose coils rob the game of power and cause parts to prematurely wear.

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Classic Bally pins don't like LEDs because they don't draw enough current to keep the circuit latched.

You can easily solder a 470 ohm, 1/4 watt resistor across the lamp socket giving the circuit enough current draw to use LEDs.

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Reserved for pic

So if you want maximum performance out of your Bally 80's pops, at minimum you will want to:

1. Clean everything. All that black carbon dust is abrasive.

2. Replace the Coil Sleeve. A new Sleeve will give the pops maximum power.

3. Clean and gap the Switch Contacts. Clean switches give the game full power. Follow the gaping instructions earlier in the guide.

4. Replace the Spoon. The old Spoon has grooves that cause it to have memory. A new Spoon will return the randomness to the game.

5. Replace worn Yokes. The fiber ones will always have heavy wear. Wear makes slop, and slop robs the pops of power that could be used to drive the ball harder.

6. Replace Ring/Rod if the rods are loose. Polish and wax the Ring so the ball will have less resistance and thus faster play. If the Ring has corrosion or a rough surface that does not easily polish out, replace it.

Do NOT overtighten the Rod Nuts. They easily break.

7. Check plunger tip for mushrooming or uneven wear. A tiny amount of mushrooming can be filed off with a fine metal file. Uneven wear is probably a sign that both the plunger and coil stop need to be replaced.

8. If the tip of the Wafer is worn (compare to a new one), replace it.

9. Replace any corroded or broken springs.

You might have to adjust the Scoring Switch gap.

got a volt meter?

Get your digital camera out, find the setting for MACRO (often a tulip flower for some reason), prick up the wires so you can see the colors and stripes, take pictures from every angle.

Tape the wires that go to the same terminal together, peel the tape off after soldering.

You can, of course, switch a #47 socket with a #555 socket.

Do a dry run and assemble a #555 bulb, in that socket in your pop body with the pop cap.

Make sure there is clearance.

If not, then http://www.pbresource.com/sockets.html

Just assemble the body, socket, bulb and cap on your workbench and see if it all clears.

If using an incandescent bulb, make sure you leave 3/16" spacing so you don't melt the cap.

You can also use a few small plastic washers to raise the cap up off the body, as long as there are no ramps or other obstructions above it.

Put a piece of paper between the pop bumper switch contacts and see if it still happens.

Usually that means you need to rebuild the flipper.

Take the glass off and manually move the flipper bat through it's range of motion.

If there is any resistance, you need a rebuild.

-

If the flipper sticks and stays up - kill the power. If it stays up without power, you know the problem is mechanical.

If the pop bumper switch has too close of a gap, the vibration of the flipper can make it trigger.

Pounding on the playfield in front of the pop can sometimes show this.

Take some clear pictures and lets see what you have.

How does the plunger tip look?

One side of the diode.

So if one diode was backwards, you would have one power wire backwards.

You can put a piece of paper between the switch contacts to rule them out.

Are you sure you don't have a diode or power wire backwards?

Usually the doubled red wire would be on the BANDED side of the diode...

Just be careful not to break off the brittle old plastic tabs and you should be fine .

Often people loc-tite them so try heating them.

If not, then grab them sideways with Vice-Grips and twist them free.

Lefty Loosey.

Probably not.

Soldering gun?