I rebuilt a No Good Gofers about three to four years ago. I didn't restore it. I only rebuilt all the assemblies with a top side rebuild. No playfield restoration was performed. I have the images from this work but I would have to find them and sort them. Unfortunately I do not have the machine available to me. It is out on loan at a friend's place. He's not too far away if I absolutely need to view it.

To start with I would look at available images of the complete playfield and try to piece the puzzle together. The manual is also helpful in what goes where. Study the manual and read it - several times. I have found that the manual contains a lot of the information required to assemble a machine. Pay particular attention to the list of playfield parts and assemblies. Lots of great information there.

If you get stuck and need help you can either take it offline (message me) or keep it public and post it here. I think the back and forth would clutter up the thread though.

Great Lakes Modular is no longer around. The website is still up but the business is not fulfilling orders.

Looks like Marco has some old GLM boards still in stock.

This board should be fairly easy to reproduce if needed.

If you want a potentially faster response, consider posting images of what you have.

I am curious to see what crazy stuff people do. Sometimes, it's mind-blowing.

The images you posted are the power inputs to the Auxiliary 8-Driver board as well as the main Power Driver board. I don't see anything incorrect about your connectors and they look to be factory. Those attached sticky labels are factory.

00_w95_auxiliary_8-driver_power.jpg01_w95_power_driver_auxiliary_8-driver_connections.jpg

It does sound more like an opto issue rather than an issue with Auxiliary 8-Driver board.

Have you considered a problem with the +12VU (unregulated +12V circuit)? This is used by the 16-opto board as well as the Auxiliary 8-Driver board. Often, modifications (mods) to the system tap this as a power source and this causes an excessive draw on the circuit and results in the voltage level sagging. When this happens, it can interfere with opto functionality.

Extremely unlikely. The flashers on this board are under software control. When things go wrong on this board, it's more likely to be complete failure (flasher does not work or is locked on). Errant flashing (under incorrect circumstances) is more likely to be errant input to the software causing errant response.

The manual lists J137 but J136 and J137 are ground. They are identical. Note the board also separates "power ground" and "signal ground" but they are tied (and used) together as a single common ground reference.

It is possible (but not extremely likely) that your functioning power boards have a problem with the +12VU but the problem only manifests under load. The 16-opto board places a bigger load on the +12VU circuit than either the 10-opto or 7-opto board. Each opto transmitter draws 0.04A (40mA) and they add up quickly.

Starting with +11.5VDC is not high enough. It should be in the order of +14VDC. Check your AC ripple on this circuit. It's possible there is excessive AC ripple and the smoothing capacitor needs to be replaced.

This helps a lot for the load reasons mentioned above.

Each game places its own load (draw) on the circuits. If the board is performing to specification, it should be able to handle the load. If the board is out of specification (partial failure), the different loads may or may not expose the failure.

Bench testing is good for logic functionality but doesn't place the load of the machine on the boards. I have tester boards available but there are also other manufacturers that provide this testing functionality. It really depends on what you want to test and how you want to test it. These testers are good to answer the question "is it on the board or is it in the playfield?".

Agree 100%. Board swapping is a good quick differential diagnosis method.

You can bench test power. For rectification you will need an appropriate transformer secondary. This will allow you to measure the AC ripple on the bench. You can deduce there is potential AC ripple if the DC voltage is lower than the expected value. If you replace the capacitor and the DC voltage goes up that's good evidence, but it's not proof. Proof would be to re-install the failed capacitor and see the reduced voltage. A repeatable experiment. Of course, that's not practical and not worth doing but it's what a true scientific experiment would entail.

Without wanting to go the full Monty with this, the next best thing is to actually measure AC ripple before you replace any components. It could also be the rectifier that has partially failed. It's a full wave rectifier and half of it may have failed. I like to measure before I do any work to know what my baseline is so that I know what has changed after I do my work.

wpc95_solenoid_secondary.jpg

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I'd suggest cleaning the slotted optos. I assume the software determines the wheel "direction" (output) by checking the switches (input). If the software isn't getting accurate input then it won't make an accurate determination of state.

Run the wheel test (assuming there is one) after you get the failure and see what it reports. I haven't seen my NGG for years now. It's been on "permanent" loan to a friend who moved it upstairs so I haven't bothered to bring it back into the annual local show rotation.

After that, I can only think that it might be a software bug. I am running v1.0 but there's a v1.3 out there. It's not unknown for WMS software to have bugs. This game in particular is likely "unfinished" since the trough expects 6 balls but the game only utilizes 4 at any one time. An example of an "errant error" is IJ. Early versions of the software report a drop target failure but the failure is due to interrupted high power so the software is unable to reset the drop targets at POST and incorrectly assumes the drop target solenoids are at fault when in fact, the power is interrupted.

This is a feature of almost all Pat Lawlor games. The pop bumper lamps in his games are controlled (part of the lamp matrix). Most other designers have games where the pop bumper lamps are part of the GI (general illumination).

I am fairly sure it relates to how many points you score when the pop bumper is "hit". An unilluminated one scores minimum. An illuminated one scores more and a flashing one scores maximum.

You will see this in games such as Whirlwind, The Addams Family and Twilight Zone (the ones I am immediately familiar with) as well. All Pat Lawlor games.