Ok, so I decided to start the overhaul on my HS after the Millionaire went "bye bye". First thing I noticed, was the batteries had leaked. Actually, I noticed that when I got the game. I removed the batteries and the old balls before I loaded it in my truck.

You can see the damage that was caused by the leaky batteries. Lots of corrosion at U41 and U42 (also a little on U51 but not bad).
P1.jpg

Here's a better look at the damage with U42 removed.
P3.jpg

I don't understand why it doesn't work...
P2.jpg

Here is the same area after removing the damaged components and treating the area with a vinegar solution for about 45 minutes (amazing the difference).
Unfortunately, a few of the vias pulled out while removing the IC's (the damage was that bad).
F1.jpg

And here is the board hanging out to dry (yeah, I hang all my PC boards here after cleaning / rinsing).
F2.jpg

Here's the board after installing the new IC sockets and PIA's. I also installed a battery terminal block (blue terminal) so I can easily add an external battery source.
F3.jpg

I also had to add a few jumpers under the board from the damaged vias and the additional battery terminal.
F4.jpg

And... voila!!

It Lives!!

F5.jpg

It needs a lot of other minor little things, like....

1 - Beacon rotary motor not working.
2 - Most of the triangular inserts are lifting
3 - Playfield has some wear (doesn't look like it's been cleaned in years).
4 - Minor lighting issues.
5 - Wiring problem in the "Clear Memory" switch. There was a shorted diode.
6 - Several broken wires.
7 - General clean up / wax job needed.

Other than that, it's in pretty good shape. It was in a guys home for quite a while (but not HUO).

I'll probably clear coat the playfield in the near future. I also think I may get the new plastic kit with the header board from Marco's.

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There was also a blown fuse in this that kept the Hideout Kickers from working. Apparently, one method to fix this problem that I wasn't aware of is to add two drywall screws in the ramp to block the ball from entering the hideout's.

(Sorry, I didn't take a photo of this before I removed the screws, but I think you can visualize the image )

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