Your favourite degreaser (I prefer Mean Green) and an ultrasonic cleaner for frames. Then tumbler for a few days. Q-tips and isopropyl alcohol for switch stacks. Yes it is tedious and no one else will know but YOU know it’s clean in there! Put on some tunes and work away at it.

I've posted about this before, but when I remove the bottom-board from a Gottlieb EM for a restoration, I carefully spray off the bottom-board with a hose and get all that dirt off. I immediately dry in the sun and with fans. Never had an issue and it gets a ton of dirt off. I can then do the small/manual cleaning of each relay, stepper, etc. as described above, but without all the dirt on the board and cloth wires.

There are lots of options as you'll likely find. How far you take it is a matter of personal preference. Options include:

- Just vacuum it out and enjoy it as it is.
- Unscrew a few of the relays, steppers, etc. at a time and brush/scrape/scrub the plywood underneath. Work your way across the board that way.
- Remove everything and sand or replace the bottom board completely.
- Wire bundles can often be brushed clean with brushes of various stiffnesses, even toothbrushes.
- Switch stacks can be cleaned with a rotary tool and a wire brush bit, or a toothbrush with a little mineral spirits or other cleaner sprayed into it. You can put a rag under the switch stacks to catch the dirt that gets flushed out.
- Relay frames and armatures can be removed for cleaning if the switch stacks are unscrewed and left more or less in place. Just be sure to keep the switches in the same order in the stack with rubber bands or whatever, and be sure to thread them back in to the armatures the same way.
- You can go the full hose-it-down route shown in the classic video referred to earlier:

It's all good.

/Mark

I take all the relays apart and tumble the frames. Wire wheel on a Dremel for all switches. I generally do not take trip banks apart though. I generally take the motor apart too. I have sanded the board a few times, only if the labels are junk and I need to reproduce them.

Clean the harness with Mean Green and a brush.

This is what I do. There are a lot of ways to restore a pinball machine. My way may or may not be best for you.

Mech Board

• Remove all mechs from the mech board. Be extremely careful to pull the mechs up and over the labels! Put the screws, nuts and other hardware somewhere safe where it won't get lost. (Do as I say and not as I do!) I need to get one of those magnetized metal bowls! You will need to remove every relay from the mech board anyway and this method is not much more work.
• It might be easiest for you to remove the labels on the board. I find it is too easy to damage the labels.
• For non-painted boards, sand down the board with large grit sandpaper. Finish with a fine grit sandpaper. Sand CAREFULLY around the labels. You can clear-coat the mech board, but I found that it darkens the wood too much and I prefer the original look. For painted boards, clean with a good cleaner. Repaint if necessary. Do NOT get the mech board wet! The wood will swell and the labels will get soaked. You can, carefully clean the labels with Isopropyl alcohol and cotton swabs, but be aware that this might remove some of the ink on the labels.
• Set the mech board aside in a safe place.

Mechs Removed (resized).png

Screws and Washers

• If you have a tumbler, you can use it to polish up the screws.
• I don't have a tumbler, so I put Mother's Mag and Aluminum Polish on an old T-shirt in one spot and some Mother's Carnauba wax in another. I manually rub the head of the screw or washer in the Mother's Mag and Aluminum Polish until it is shiny. I do the same with the wax. I then do the same on a clean part of the cloth to finish.
• As you take apart the assemblies, the score unit for example, clean the screws as you go and keep them together! They are easy to lose!
• Shiny screws leave a professional look to your work.

Clean Screws (resized).png

I no longer use rubbing compound. I now use Mother's Mag and Aluminum Polish, polishes to a bright shine and protects.

Stepper Units

• Take a lot of pictures of stepper unit from every angle!
• Take all stepper units apart, clean all loose parts in the sink with Bon Ami and Gain dishwashing soap, using a toothbrush.
• Sand any surface rust down with 500 grit sandpaper and blue glass cleaner.
• Optional: Polish copper gears and parts with Mother's Mag and Aluminum Polish. Just buy it. Great stuff!
• Remove any remaining dried grease and oil with Isopropyl alcohol, especially on the gear teeth.
• Remove the cotton from a cotton swab and using Isopropyl, clean out the shaft holes in all nylon pieces.
• Using a cotton pad and Iso, thoroughly clean the shafts on the stepper unit base. Continue until cotton pad is clean.
• You can polish up the stepper metal base with Mother's Mag and Aluminum Polish, but I usually just clean it off with iso.
• I used to put some SuperLube on the parts with metal to metal contact, but not so much anymore. Put some on the teeth of the gear though - only the teeth that interact with other stepper unit parts.
• I used to use fine sandpaper to clean the stepper unit contacts/rivets and spider contacts. I now use Mother's Mag and Aluminum Polish, I shines up beautifully and the contacts are as smooth as a baby's bottom!
• Put the stepper unit back together again!
• Check for loose or missing wires. I had an Aztec that had a lot of bare wires on a stepper unit. This can wreak havoc when the game is turned on. Remove any bare wires, use shrink tubing to cover the bare spots and solder back on. Do this one wire at a time!

For more detail about disassembling and cleaning a stepper unit, read this post:

https://pinside.com/pinball/forum/topic/bally-1970-double-up-minimalist-restoration#post-2949171

Relays

• Clean all contacts and switches with cotton swabs and Iso.
• Using a Dremel with a #443 wire brush, polish the contacts until they are bright and shiny. I used to use burnishing tools and 500 grit sandpaper but this method is far superior.
• Clean all contacts, again, with cotton swabs and Iso
• Look for missing springs, loose wires, missing wires, anything that is 'wrong.' Lightly pull and move each wire. Sometimes the wires appear to be soldered on properly but may actually be loose. This is rare but cause intermittent problems that are hard to track down. The wires tend to get bent down and flattened over time. I like to restore them to 'loops' when testing the wires - just that extra little touch that looks nice when done.
• Optional. Clean the metal relay base and the edges of the spacers with a cotton swab and Iso. It's amazing how much dirt and grease will come off!
• Tighten all switch screws with the proper-sized screwdriver.
• Using a switch adjustment tool or small regular screwdriver, adjust all switches so the switches are open when they should be and closed when they should be. The gap should be about 1/16 of an inch. Manually move the armature to mimic when the relay is energized. Normally open switches should now be closed and normally closed switches should now be open. The key word here is deflection. Does the switch move just a tiny bit when the switches are opened and closed? If not, you may not be getting good contact and, over time, the switch will come out of adjustment more quickly.
• Check each switch by manually moving the relay armature to confirm the proper gaps, closed switches that open and open switches that close. Then, go back and double-check your work. Later, when the mech board is put back into the cabinet, repeat the process for each relay and switch. Switches can come out of alignment when bumped during work on other parts on the mech board.

For more information about cleaning and adjusting relays, read this post. Please note that this post was made before I used the Dremel #443 brush to clean contacts:

https://pinside.com/pinball/forum/topic/bally-1970-double-up-minimalist-restoration#post-2958141

Jones Plugs

• Clean all male plugs with iso and Dremel #443 brush
• I move the male Jones plugs up and down in the female Jones Plug to, at least, try to remove some of the dirt and to make better contact. Sorry about how that sounds! I still haven't found a good way to clean the female contacts. Anyone?
• Look for loose or missing wires on the Jones Plug! These problems are very hard to track down, so make sure now that all is good.
• You can clean up the rest of the Jones Plug with Iso and cotton swabs if you like. I always clean the area where the screws are since these areas collect dust.

Tools

• Cotton swabs - I like the paper swabs. The cotton comes off too easily on the plastic swabs. I like Q-Tips. They cost more but hold up better in use.
• Cotton pads - I was getting the expensive pads at Walmart and found that the cheap 100 for a buck pads at the local 99¢ store were good enough.

This is a thorough restoration and may not be appropriate of you are doing your first electro-mechanical restoration. Only you can decide that.

More to come.

WARNING! This Forum is full of threads where a beginner took a machine apart, cleaned it and brought it back to 100 %. Go for it, isn't rocket science.

This will raise the roof but here goes: Go to the auto parts store and get a couple of cans of spray brake cleaner. It will cut thru all the grease and grime.

Remove your relay board from the cab and set it on a table or anywhere you can spray.

The brake cleaner is flammable so let your board and relays dry for a few hours before you apply any power. The cleaner will evaporate fairly quick but your wiring will be wet. To be safe, wait 24 or 48 hours before you apply power.

You can speed up the drying by placing a fan and letting it blow on your parts.

This is my go to method. I also remove the head board then remove the replay wheel from it and spray it with brake cleaner. Just avoid spraying anything that has ink or paint on it. Let dry completely. Never had any issues.

Do it outside if possible, that stuff is stinky!

Can't steal someone else's schtick...

There is no way I'm pouring water on an electrical panel. Just a basic reality check...Water and wood do not mix. It creates expansion and warping. Anybody that has any REAL experience with electrical panels would agree, Water and wire harnesses do not mix. Especially, cloth insulated wiring that is 50+ years old. Old cloth wiring has an tendency to shrink due to age...add water? It's just idiotic.

Mark (The hot water guy) may have a nice and shiny game after a 48hr dryout, but that game failed and is ruined.

Peco on the other hand, is demonstrating years of experience and dedication to the our hobby and profession.

There are no shortcuts in ANY profession.

Here is the basic information I pass on to new pinheads.

1- Buy a game that works.
2- Develop a thorough understanding of EM logic.
3- It takes hours and hours of dedicated detailed attention that makes a game play and look special.
4- Enjoy the game and NEVER use any water based products on the playfield or logic boards.

Easy tiger!
When I started the games I bought were not working. Key you missed is to take a lot of pictures. You can learn on the fly with the tutorials available.

I am not working on games that have 50-70 years of filth over them as they won't work right and problems are hidden. So as part of my strip down the cloth wire will get a one off hot bath in my ultrasonic and a degreaser + water, gentle scrub with a tooth brush and 90% of the gunk is gone. Never an issue afterwards.

The Mark reference I guess is to the video of the Dutch bingo guys. I contacted them about the cleaning method years ago and understand why they start there restoration process that way is because they are a professional successful operation that will not work in filthy conditions. The games are never ruined the cloth wire nor the wood.

I agree with your other points if you want to have a long positive experience in restoration of EM's.

For what it’s worth, I’ve had success in brightening up relay labels by lightly rubbing them with a pencil eraser. It worked better than alcohol.

Did not intend to ruffle any feathers...but the original post was a good question regarding cleaning the bottom logic board. I wouldn't recommend pouring hot water on any electrical component, especially to somebody who is just getting out of the gate with pinball restorations. So I guess my question to you is:

After viewing the video of the hot water rinse down...you endorse this?

I take everything off the score motor board, remove all the labels, and sand away the embedded dirt and discoloration. Sometimes the labels can be cleaned up and re-used, but lately I’ve been replacing them.

All the hardware gets dismantled for a deep cleaning/polishing and mechanical rehabilitation. It takes time, but the end result is satisfying.

Score Motor 3 (resized).jpg

No endorsement here, it would be excessive to use this method of cleaning for a pinball we find in the US. Possibly your post was a little too black and white and water can be gray

This video was made by a company that is very respected in Europe and provides mint vintage bingo games to the public that wants a perfectly working game. The condition of the bingo games is much worse in the back box by the use of neadsfoot oil in the lubrication of the control and mixing assemblies. I spoke with Frans a friend of Coo's and they still do this cleaning when the game is bad. The use of the magic cleaner in the original video as 'Frans' admits is a caustic(sodium hydroxide) cleaner we don't know the strength but just look at how the grime washed away.

Here is a link to a 6 year old thread. https://pinside.com/pinball/forum/topic/how-do-you-clean-cloth-covered-wire-harnesses#post-1392482

There are a few topics here in the last 5 years that discuss the use of water and always have this video attached (I am guilty for attaching it sometimes). The reality is that games that are particularly smelly can benefit from having their cabinet and bottom board washed in Clorox and water. The games I have done this to had no adverse affects. I put motor/gearboxes and relays (not the wrapper) etc in the ultrasonic and they come out as new. I use compressed air to expel excess water and air dry for a day or to. All my games after the 6 month restoration cycle work perfectly including my bingo and have done for years.

I discussed this recently with two well known experienced bingo enthusiasts and they had a concern that they have evidence of older bingo's wire failing but this is as I understood is more to do with the coated wire under the cloth having age issues. We agreed that one good wash in their lives may be enough (or they listened to me and grunted acceptance i think).

It just blows me away!

WD-40 electrical contact cleaner. It is amazing for pinballs and other electronics. It is non-flammable, and dries almost instantly.

You can find it at Wal-Mart, Lowe's, Home Depot, etc.

It is a secret trick of some of the best pinball restorers/techs out there.

Is this a joke? Highly flammable and really has no place in pinball repair.

This is what he's referring to
https://www.wd40.com/products/contact-cleaner/?specialist=GoogleBrand&gclid=Cj0KCQjw_ez2BRCyARIsAJfg-ks-gbxuy2zcRABEJxG5Dliyc9FZ7zSV5oLaO4TAd3utN_g22rKq0ZUaAiOwEALw_wcB

Reading the Tech sheet on the link:

"DANGER!
Extremely Flammable Aerosol."

"Keep away from heat, sparks, open flames, hot surfaces. – No smoking.
Do not spray on an open flame or other ignition source"

"Use only outdoors or in a well-ventilated area."

My view would still be that it has no place in pinball repair.

Yes, do NOT use other WD-40s.

The electrical contact cleaner is only flammable when wet. So, about 2 seconds.
They have to put the disclaimer as a fail safe.

I learned this trick from one of the top restorers in America, and come to find out...a lot of the most respected restorers use it as well. You never hear about it because these guys don't share their tricks of the trade.

Watching that video is super satisfying! I'd totally do that if I had an EM game that needed a good general cleaning.

The effort/hours invested between that approach (esp if the game is working) vs tearing down and rebuilding everything is not comparable. Both work depending on what you are trying to achieve.

Brake/switch cleaner idea is also reasonable though keep in mind you don't want to be breathing that stuff in and not a great environmental choice.

You can totally wash SS circuit boards with water too, just need to make damned sure they are fully dried before powering them up again.

If one does not know how to handle flammables, then I agree. But brake cleaner and contact cleaner evaporates. It dries out and leaves no residue behind. They are best used outside. And let the pin dry out for a few hours and you will have no problem.

As far as washing down with soap and water, the metal parts are mostly brass and copper. Water is not going to hurt those metallic parts. If water were to destroy the wooden base the relays are mounted on, go get another piece of plywood---unless having that original piece of plywood means something.

That looks amazing. How do you reprint the board labels and get the right font, spacing, etc?

I scan them, bring them into Photoshop, and rebuild the text using Futura, which is a pretty good approximation of whatever font Gottlieb used.

Atlantis (resized).png

Take the bottom board outside, put a tub or shallow pan under it, lean it up against something, and hose it down with aerosol brake cleaner.
About two cans worth will clean the grimiest board, and will clean the wiring too. Let it air dry thoroughly, or use an air gun to speed up the process. The labels and relay stickers may not fare very well, but they won't in a water bath either.

Edit: I rewound about a year back, and see that this method has been proposed already.

This is what I'll be doing to my Spanish Eyes. Both the bottom board and the head board. There's grime, grease, and gunk in there. I was thinking of going the simple green, scrub, and hose route, but I think brake cleaner will be much more effective. I'll spend the money on 4 bottles of brake cleaner if it'll save me 75% of the time.

Staying with warm water and a diluted Zep Citrix orange degreaser in my ultrasonic until we get this concern resolved.

I've used a font called "Intrepid" to approximate the text on S/I cards.
It's very close to the original.

this is good feedback. I thought with the cloth wires, that color wouldn't be affected. What game was this on?

Might you have the bottom panel labels from a Capt Fantastic in your files? Mine had seem some water at some point (I'm assuming) and most of the labels are so far gone, you can't read them.

"WD-40, repairman in a bottle". Please keep the repairman in the bottle

Spanish Eyes is '72. I wonder if the 5 years difference will make a difference with the wire bleaching. I guess I'll see if I have some brake cleaner in the garage before I go and get a few cans.

As with anything else, spot test it first. I haven't had any issues using the brake cleaner. I've used a product called "Brakleen".

That's what I typically use as well. They make a chlorinated and non-chlorinated version. I wonder if the chlorinated version is what can cause the color of the cloth wire to "bleach" since bleach is chlorinated as well?

What kind of brake cleaner did you try using?

Sorry, no.

Wow, that is an amazing board. It looks like those parts have been chrome plated. They were never that clean out of a factory. Very impressive.