So, the boards didn't come from the factory with sockets?
There are 13 sockets just on the MPU board alone not including the ones on the driver board.
whoever soldered those sockets on looks to me like they knew what they were doing judging by what the back of the boards look like.
I'm no circuit board guru but I know a hack job when I see one.
What do you mean by "makes it really sketchy"?
Do you think these boards are repairable or not?

Also there are sockets on the opposite side of the board away from the battery holder and no sign of battery corrosion at all....I wonder why sockets were installed when there was no corrosion around them?

The only part of the board I cleaned was where the battery holder was and just below it. I didn't want to get anything wet that I didn't have to.
Again, I'm no expert but the board doesn't really look all that bad at all to me.
I am just concerned about sending the three boards and $249.50 in to get "refurbished" , then get a call saying it will be more money to fix them.
That's why I was asking if anyone has used this guys services before...maybe I should have started a new thread since this one is so old.

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That's way too much. You might as well get a replacement board instead.

There are several reputable repair guys who are much more reasonable.

Only for the eprom/rom chips, but a different style of socket was used.

Socketing an entire board is one way of "shotgunning" the repair (replace everything). Of course, there are also times when solenoid voltage gets on the data bus and destroys all ICs that share the pins that get the HV.

No reason to pay to repair the other boards if they aren't damaged.

But yes, you also need to at least replace the female molex interconnect connectors as those internal leafs will start breaking if they got the alkaline too.

Any recommendations?

But wouldn't it be a good ideal to have the driver board refurbished and the power supply too since the MPU is gonna have to be done?
.....and I don't even know if there are issues with the driver or supply boards anyway

This method seemed decent and there was definitely a reaction when I tackled a WPC-89 MPU with decent corrosion. I bought my STTNG from some electronic engineer guy in Maine who has been in the pinball biz on the side for awhile. I'm no engineer nor an expert but I know enough to get in trouble and I'll let you be the judge on whether or not you'd trust this board to work five years from now. As you'll see I did start the tear down and will show progress and completion pics in the next post:
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Here's the board stripped and ready for cleaning. You can see the damaged traces that were the cause of the jumper wires on the back of the board. You can also see a good amount of the dark "shadow" PCB that has the corrosion deeply embedded.
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Sleeping my day away? Try scrubbing my day away.

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I did two acid brushings with each pass followed up by being rinsed with distilled water and scrubbed well. Unfortunately it wasn't enough so I had to bust out the sand paper and go to town on the embedded corrosion.
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I then used some solder braid and wicked solder all over the traces to cover the copper up.
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Here's the done picture before cleaning off the remaining flux. Unfortunately I didn't take a pic after to get a cleaner shot but hey the corrosion is gone.
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No way he was an electronic engineer with the solder job on those rear wires, LOL.

Congrats on extending the life of that board another few decades!

Most EE's I've ever worked with don't know what a soldering iron looks like.

Even if they didn't, they would hand it over to the tech guys and say "fix this, and bill an hour to my department".

I know a lot of Engineers that we shouldn't let drive the train....

There are way better options out there. I would stay away from this by all means. I had a bad experience with this repair guy. I sent him a board that was having multiple problems. What I got back was a total mess with jumpers everywhere. The board did work but I had a problem in the way he got it working, it only made it three months by the way. The seller had no communication, terrible repair and was very slow on repair and shipping. Good luck on finding a good repair guy.

I second that. Stay away from "Classicgameparts" on Ebay the guy is a hack. Way overprice for the low quality of work that he does. I ended up fixing the board again after he so call fixed it.

Oh my, I fell for this and I had the same exact experience with this guy. Sent boards to him in May, ad said I would have them back in 2-3 weeks. Finally got them back in October and he sent me an MPU that was not mine. Took at least another month to get my MPU back and I'm now left to rebuild my driver board again myself. Going mosfets this time.

Crap, horrible quality work, took months longer than estimated, would barely respond and I'm left redoing his work. Actual website is http://www.pinballrepair.net/ (confirmed, I called). STAY FAR FAR AWAY.

This was for my first pinball I bought Flash. Was a newbie and didn't want to do more harm than good, didn't yet know about this site so I fell for the ebay ad.

BTW I have used "The Works" toilet bowl cleaner with success. It's found just about everywhere and it's dirt cheap ($1.65 at Dollar General stores). https://www.dollargeneral.com/the-works-disinfectant-toilet-bowl-cleaner-32-oz.html?gclid=Cj0KCQjw-uzVBRDkARIsALkZAdlXbu0pqBMM5ha55HZcICvBetzzcXx6i-_Oxp7FZfdKm4PFeQxML_MaAkKMEALw_wcB

It is thin and runny though, not like the gel which I'll have to try.

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Check your label carefully.

"The Works" that they sell at my local store is Hypochlorite based - the opposite of what we need.

HCl = Hydrogen chloride - one atom of hydrogen, one of chlorine. Mix it with water and you get Hydrochloric acid.
http://content.rpgov.net/dpw/right_to_know/Libary/The%20Works%20Toilet%20Bowl%20Cleaner.pdf

Right.

The Works says Hypochlorite on the $4.98 bottle, I could not find the cheaper one.

I think your use of the word "chlorine" in post 69 is misleading. Chlorine is found in both acids ( like HCl-used to clean alkaline damage) and bases (like sodium hypochlorite- a bleach/disenfectant).

Maybe your local store has something with sodium hypochlorite?

Who knows?

It's just like when everybody for years used Formula 409 to clean their tape head rollers .

Then one day they apparently changed the formula, and it started pitting all the rollers it touched.

Nothing on the label saying "New and Improved" or "New Formula 410", just pitted expensive rubber.

I changed it to Hypochlorite.

Thanks, I see how that could be taken the wrong way!

Here’s what my “The Works” label reads.

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Bump

Just used this process on a Flash Gordon CPU with acid damage. Started with the vinegar route and then came across this thread and it seemed to be a better route. This is my first alkaline damage repair, and so far am very pleased with the results. If someone sees something that still looks bad before reassembly, please let me know. I used this Lysol brand that is 12% hydrochloric acid and waited 5 minutes on each side after scrubbing with a small brass brush, rinsing with hot water, then alcohol, and then blow dry with the compressor. I'm now waiting for the "corrosion rebuild" kit from Big Daddy so I can start to assemble.

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Went to play some Tri-Zone a bit ago and it didn't work. Doh! Never took the batteries out.... not a lot of damage so I'm going to give this method a go at it. Looks like it will work great.

Everyone mentions a brass brush..... anyone tried the brass brush wheels that you can get for a dremel tool?

https://www.menards.com/main/tools-hardware/power-tools-accessories/power-tool-accessories/abrasive-wheels/dremel-reg-1-2-brushes-2-pack/536-02/p-1454046437407-c-10154.htm?tid=6884497976735199426&ipos=1

Seem's like a no brainer there, but maybe there could be some issues if you have the dremel on too high of a speed. Might be quicker over all though if you get the speed/pressure right. Going to give it a go sometime soon and see what happens.

I already use these guys for cleaning up connector pins and chip legs.

https://www.menards.com/main/tools-hardware/power-tools-accessories/power-tool-accessories/rotary-tools-accessories/dremel-reg-detail-abrasive-brush/ez471sa/p-1444452428354-c-1537277164191.htm?tid=16735882553821792&ipos=1

Especially on the large EM plug connectors. You can get in between the pins with ease and shine them up real good for a like new connection. No more flickering lights!

I use the steel dremel brushes. They work well.

Just got a Champion Pub with leaking batteries. I've replaced them and the game is running fine but at some point there will be problems. What do you guys recommend I do? I can see corrosion on U5, U27 and U11. I bought some Zep Acidic Toilet Bowl Cleaner but I wanted to check here first before I screw something up.

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Remove socketed chips and ASIC (with the proper tool--not a screwdriver!). Use zep to remove surface corrosion (use a soft toothbrush to agitate) and rinse off board with water. Remove affected components and sand off the masking on the affected traces (but be careful not to do too much, since the traces are very thin). Use zep to remove corrosion from traces, and rinse with water. Sand and repeat if necessary. Final rinse with water, and displace water with alcohol. Blow out droplets from under chips/components with air compressor at an appropriate pressure. Let air dry. Solder in new components (don't reuse the affected ones you removed!), clean off flux, and seal exposed copper with clear nail polish.

Thank you for the help.
Is it okay to use regular water? Do you know where I can get all three chips and it looks like I'll need to replace C76.

Yep, it's safe to use to rinse, but I usually like to use alcohol to finish up to ensure no contaminants/minerals get left behind.

Pinball or electronics suppliers. Simply to a search for the part number on the chip starting with "74", such as 74LS240. Electronics parts suppliers would probably be less expensive.

If you have the proper tools, you can remove the chips, clean them up, and reuse them. None of that is heavily damaged, no reason to replace.

You can do initial clean up on the board with the acidic cleaner to remove the corrosion. That will make removing the chips easier. Then clean again after removal and seal with nail polish. Install the sockets and you are good.

Same goes with the ceramic cap at C76. After some clean up it will most likely be fine.

It's better to replace a 25 year old electrolytic cap if you're removing it anyway. It's probably nearly dried out at this point.

Oh, yeah, I agree. I thought he was talking about the ceramic at C76, that's what I was looking at and talking about. I was looking at the corrosion on the board and didn't even notice the blue cap. I edited my earlier post to clarify I meant C76.

Thank you for your help guys!

This is a little unrelated as it’s corrosion OFF the board (but close).
It’s my Safe Cracker. The MPU board has been replaced with a Rottendog, a sign that there has been a problem. When I took the board out the other day, I noticed alkaline corrosion on a couple of the screws and their housings. The board itself is unblemished.
My question is, can a get away with giving them a bit of a wipe with a vinegary rag, or do I need to pull the whole metal backboard out? I will have to take all the boards out if that’s the case.

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I'd use the Zep toilet cleaner with acid, it works great! $4 at Home Depot.

Then how would you rinse it clean? Don't want to just leave zep on there and put a new board in!

Since it isn't a delicate board, and just a metal bracket, I would start by probably brushing off what you can (soft or even small wire brush if needed). Then if you are worried about it, maybe a soft bristle brush (toothbrush) dipped in something to neutralize.

The debate of what to use to neutralize is up to you. Personally, I'd be happy with a couple of vinegar scrubs, then maybe a little warm water on brush a couple times. That is just me though; only because if I used anything stronger, I would want to do a heavier rinse....kinda hard inside backbox I'm guessing.

Edit: Does anybody sell a similar replacement stand off??
That would really be best of course. Still scrub wood with something, then install new sure sounds nicer.

How would you rinse if you use vinegar?

Since it is not acid, baking soda will not work.

Agreed, not the best. That's why I mentioned a toothbrush soaked in warm water a few times to rinse what you can. Since, no this isn't as good as full rinse, I was just saying that I would be concerned on using anything stronger in place. Like I mentioned, Zep type acid being so much stronger, would make me personally feel better to be sure it was rinsed even better is all.

Not saying right or wrong at all.

I didn't realize that had clips can come out and be reused. Obviously, taking out, soaking, and rinsing well will be best! Then, while they are out, the backbox can even be scrubbed and wiped a bit too. Nice.

Wish I could find this stuff in my area. Anyone want to ship me some to Parma Ohio lol

Also didn’t realise this, that’s a great help!

You could have it shipped from home depot or lowes, if it's not on amazon.