This page describes my project of restoring a Williams Time Warp pinball machine, and how I got into pinball repair in the first place.
I have always been very fond of pinball machines, and after having created my SpiffMAME cabinet I decided that it would be cool to look into owning a pinball machine as well. The primary reason for sticking with the arcade machine in the first place was that it takes up a lot less space, and you can have a multitude of games on the same machine. This is not true for pinball machines, so getting into this hobby requires more room.
I have helped a friend restore his Silverball Mania, so I had already been introduced to this exciting hobby, and had an idea of what was inside one of these machines. There is no doubt in my mind that I will at some time have a room with at least a few pinball machines, along with my SpiffMAME cabinet, and perhaps another one or two arcades, and a jukebox. So far I do not have the room for this, though, and so this will remain a dream for now.
In order to use less space, but still have some pinball nostalgia, my initial idea was to create a coffee table with a playfield from a pinball machine. I did some research on where to find a usable playfield, and although the condition of the playfield in terms of wear was not important, I wanted a playfield with a nice background image, a lot of lights, and all plastics should be in good shape. I checked some prices, and also told a few friends about this project.
A friday as I was coming up the driveway, a friend calls me up and tells me that there is a Williams Time Warp pinball machine standing outside his office, and whether I would be interested in having it. I couldn't believe this, but he checked with his manager, and called me back and told me that I could have it if I came and picked it up. I got into my dads station wagon and drowe down to meet my friend.
Of course it turned out that I had forgotten the bag of tools I packed, so we had to make a stop by his place to get some tools. Luckily the machine was not locked. It turned out that both of the locks (the coin door and the backbox) had actually been forced open, but this was much better than not being able to open the machine, since we did not have any keys for it. Luckily there is no aparent damage to the backbox or coin door, so getting a new pair of locks should take care of it.
Taking out the back glass and opening the backbox allowed me to unscrew a couple of bolts securing the backbox. All wiring from the playfield and coin door to the backbox have connectors, so these were unplugged. I took the backbox off and put it in the car. Then I removed the two back legs while my friend was holding the machine, and after this we were able to slide it in the trunk and take off the front legs.
I got home with the machine, and did take a few looks at it, but had no chance of getting it inside yet.
I spent the entire Saturday cleaning out the basement in order to make room for the machine, and Sunday (after cleaning out the basement stairway and going to the dump-site), my dad gave me a hand carrying the machine down in the basement.
Initially it was just sitting on the floor, without the legs mounted, and the backbox next to it. I got it onto some work-tables, allowing me to open up the machine and take a look inside. Unfortunately tha ceiling in the basement is quite low, so when the machine is standing on the work-tables there is not enough room to put on the backbox. So I have not yet had the chance to connect it and try powering up the game.
Here is a picture of the backbox:
There is a little damage to the artwork on the back glass, mostly on the right side of the player 2 score display, due to the backbox not being closed properly before the back glass had been inserted. Other areas show a little wear as well, but so far this does not seem very noticeable, although getting the light in the backbox turned on may change my opinion on this. So far this is not a top priority, but hopefully I will be able to make it look decent in some way or another.
I took out the player 1 display, as it was broken:
I took a look on eBay, and it looks like it should be possible to find a replacement.
I also found a bag of spare parts inside the machine, and replaced a few bulbs on the backbox, which had been crushed (along with the player 1 display). I searched the web for some information on maintenance and repairing of this type of machine.
After taking off the top glass, I took a few pictures of the playfield:
As you can see on the image, there is a lot of wear and tear on the playfield artwork. A few rubber bands were missing, and the remaining ones were very fragile (and basically unusable). So I will be getting a new set of rubbers. Also notice the banana-shaped flippers used in this machine. I actually found a web-shop stocking new rubber covers for these, so they will be replaced as well.
But all plastics on the playfield seem to be in good condition. This is nice, since getting replacements for these can be quite difficult, since they are game-specific.
Removing the protective cover on the bottom part of the play-field reveals the coil used to kick the ball up to the plunger. This part seems to be in good shape.
Flipping up the playfield (no pun intended) shows all the coils, lamp holders and other mechanics on the underside. These seem to be in great shape too:
I opened up the backbox and got a picture of the insides. This also looks pretty nice, but since I have not yet connected the machine, I cannot tell if the electronics start right up, or some tinkering is needed.
Finally, here is a picture of the legs. Notice that one (the 2nd from the top is gray, rather than chromed. Also, the design is slightly different. There were only screw-stand mounted on the two back legs, but these should be readily available. I'm more concerned about the leg.
At this point it seems quite doable to restore the machine, and so I will not us the playfield as a donor for my coffe table project. Whether I end up having too little room for this machine, and need to sell it is yet unknown, and may also be heavily influenced by how much time I spend on getting it working, and whether the game is any fun. But so far this is the beginning of my adventure into restoring a pinball machine.
The machine has been mounted back on the legs. This makes it low enough that it is possible to mount the backbox. Trying to power up the machine, the only thing that lights up is the displays, showing the audit mode. I took a look at the fuses in the backbox and noticed a blown 1.5A fuse. After replacing this I turned the machine back on, and the General Illumination (GI) in the backbox lit up for about half a second, before the fuse blew again.
After finding some information about repairing Williams pinball machines, I discovered that the GI fuse was actually supposed to be 20A. No wonder it blew when I put in a 1.5A fuse. Luckily it actually turned out that there was a spare 20A fuse in the little bag of spare-parts I found inside the machine. After replacing the fuse, the GI circuit worked better, and I now had GI lights on, but only in the backbox.
Taking a closer look at the problem with the machine starting up up in audit mode, I discovered that this normally happens if the backup battery for the settings and high-score is dead. An external 4.5V battery had been mounted in the bottom of the backbox, with wires connected to the battery holders on the CPU PCB. Since this battery looked very old, it was removed and discarded. I then mounted an external battery holder and put in 3 new AA batteries. I measured 3.62V on the 5101 RAM chips power supply pin (IC19, pin 22), so new batteries were connected correctly, but the machine still started up in audit mode, and even the suggestion of quickly powering off and on again did not work. Also, pressing the diagnostics button on the CPU board lit up both LEDs. This suggests a defective 5101 RAM.
I found a guy who had a spare 5101 RAM, which he was willing to sell. The old one was removed by taking a pair of wire-cutters and snipping all the pins of, then removing/desoldering the pins one by one. I mounted some pin strip connectors, acting as an open-frame IC socket (I did not have any sockets with 22 pins and the strange in-between width that this RAM-chip uses).
Mounting the new 5101 and starting up the machine, it still went into audit-mode, but when pressing the diagnostics button the LEDs flash briefly, but then turns off again. Also, now the trick of powering off and on quickly allowed the game to come out of audit mode. :-D
Activating the coin-switches I was able to start a game. A few sounds were heard in the speaker (after turning it up a bit), but no solenoids were working. This included the one to kick the ball up to where the plunger is, so it wasn't really possible to play the game yet. But hitting various targets would actually score points, and sound various sounds.
I had ordered some new locks off of eBay, since the old ones had been damaged and there were no keys. The locks were replaced when this shipment arrived.
When I had the CPU board out to replace the 5101 RAM, I had to take out the solenoid driver board, since these are connected via a board-to-board connector. When handling the solenoid driver board I noticed that one of the TIP122 transistors was broken (physically snapped in two pieces). Testing the others with my DMM I found that another one was shorted. I unsoldered those two and ordered some spare parts for the PCBs. First of all, the TIP122 transistors. I also ordered a bunch of 2N4401, although these did not seem to be broken. Then I wanted to replace the 27Ω power resistors, of which there are 8. These also seem to work, but are slightly burnt, so they will go. Also, the shorted transistor probably blew the fuse for the solenoids. I checked all the fuses in the game and found that both the flipper and solenoid fuses were blown, so I ordered a bunch of different fuses as well.
I ordered spares of all electrolytic capacitors in the machine, except the large storage capacitor for the lamp driver voltage. This one would cost around $30, and I discovered I already had one, which was 68000μF instead of 30000μF, but this will just smooth out the voltage some more.
I decided to also check why there was no GI lights working in the playfield and coin door. The coin door issue was due to a wire that had been cut. Soldering the wire in place gave nice light in the coin door.
Then I started checking the connections from the power supply to the GI circuit on the playfield. These appeared to be OK. I had originally thought it was a fuse, but looking at the schematics, there is only one fuse for all the GI. Then I thought it had to be a bad connection between the power supply and playfield, but now this seemed to be OK as well. Finally I discovered that every single one of the GI bubls were blown. My guess is that the playfield has been hooked up incorrectly at some point, either by orienting a connector the wrong way, or hooking it up to the wrong connector. This will have given the GI-circuit too much voltage, and all the bulbs have blown. I replaced all the bulbs in the GI circuit of the playfield. I did not have spares at this point, so I took them from the backbox. Also ordered 100 EIKO #44 bulbs, so when these get here, I should be able to get it all lit up. Looking at the playfield all lit up is so much nicer. Although the damage to the artwork on the playfield is looking bad, a lit playfield gives the real pinball atmosphere:
When I got the components, I did some restoration of the PCBs, starting with the driver board:
As you can see from the above image, I had already removed the two defictive transistors. The board was cleaned with rubbing alcohol on a small stiff brush. Then the two broken transistors were replaced, along with the electrolytic capacitor. I also replaced the eight power resistors with ceramic 7W types, although the original ones were not broken. One of the old ones had a resistance of about 42Ω, and the others were still good, but looking slightly burnt. If I had known about the trick of using FETs instead, I had done this, and replaced the resistors with wires, which would have avoided the heat generated by these resistors. But now I have already spent the money on the power resistors, so this is not top priority.
After the restoration, the driver board looks like this:
Next came the CPU board. Before starting it looked like this:
As I had already replaced the 5101 RAM, putting it in a pin-strip socket, all that needed to be done on this board was replacing the electrolytic capacitor and the wiring for the external battery holder. Of course a little cleaning with rubbing alcohol was in order on this board as well. End result:
After replacing the battery wiring, the machine now starts up correctly and not in audit mode. Excellent. I think I'm getting near on the electronics side.
Then there was the power supply board:
This was mainly replacement of the electrolytic capacitors. Notice that I was unable to find an axial capacitor to replace the 12000μF on the right, under the heat sink. I found a 15000μF upright type, but by drilling a small hole through the PCB, I was able to wire it nicely. Actually the trace that it needs to be connected to was available near the existing hole on the bottom side of the PCB.
The fuses for the solenoids (F2 - 2.5A) and for the flippers (F4 - 10A) were both blown, so I replaced them. This is what the power supply board looked like afterwards:
Finally, there was the sound board. I had been fooled by Time Warp being a System 6 machine, but it turned out the sound board is actually a System 3/4. Before restoration:
As with the other boards, I replaced the electrolytic capacitors. Since I had not found the schematics when I ordered components, I had missed the 33μF capacitor, so I had not ordered a replacement for this. I therefore put an 18μF and a 15μF in parallel. Later I found out from the schematics that this was just another decoupling capacitor for the 12V supply. A 100μF could probably have been used with no problems (and it would have looked nicer).
Once again, the 12000μF filter capacitor was replaced with an upright version. On this board I had to run the wires a bit longer in order to mount the capacitor to the PCB with a cable tie.
The socket for the sound ROM was replaced with pin strip sockets. I haven't replaced the socket for the CPU, and the PIA isn't even mounted in a socket. If problems occur, this will probably be a good thing to check.
I also replaced the fuses with some known values. I used 2A, but later found out that the fuse rating according to the schematics was 4A. I haven't had any problems with this so far, so I will keep the 2A fuses unless thay blow.
After fixing the sound board it looks like this:
When all the boards were installed in the machine, I powered up, and since the solonoid and flipper fuses had been replaced, I was now able to start the game. I didn't really play much, since I had removed all the rubbers from the playfield, since these were worn and brittle. Also, I later noticed one of the pop bumpers being stuck on. At that point the machine had been on for a few minutes, and when I noticed, the coil was very hot. So I turned off the game, and checking the resistance afterwards it does not seem like the coil has been damaged.
Another thing I bought on eBay were two VFDs. As one of my initial observations when looking at the machine was that one display was broken, I had checked the options of getting a replacement. I got two of them, and although they came with no warranty, they both worked fine.
I also got the #44 bulbs and replaced the ones in the back box, which I had removed earlier when changing bulbs in the GI circuit on the playfield. It's really starting to look nice:
When the game is in attract mode, I noticed that there is a buzzing sound in the speakers when all the lamps flash. I originally thought this was due to the large lamp matrix filter capacitor being bad (dried out). Since a new capacitor of this size would cost about $25, I decided to look in my parts bin, and found a 68000μF 30V capacitor, which I decided to use. Although this was more than twice the specified value, I figured this would just help smooth out the ripple even more.
After replacing the capacitor I turned on the gama again, but the buzzing sound in the speaker persisted. Then I looked at the sound board schematics, and discovered that the relatively low voltage signal carrying the sound is routed out through J4 and down to the volume control in the cabinet (inside the coin door). Then it runs back to the amplifier on the sound board and then out to the speaker. What had happened was that the amplification on the sound board had been turned up high, and the volume control in the cabinet had then been used to turn it down again. In other words the signal running out through P4 on the sound board was reduced to a very small voltage swing, and then amplified afterwards. Of course this made the sound more vulnerable to noise being picked up in the wire from the volume control and back to the sound board amplifier. And although this wire is shielded it runs along with the others to the playfield, along with the ones for the lamp matrix. So turning down the amplification on the sound board and up on the volume control inside the coin door solved the problem.
I think I will put back the 30000μF filter capacitor, since this fits in the mounting bracket in the bottom of the back box.
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