Repair & Maintenance Log

10/13/06: Acquired game at the Whiterose Gameroom Show in York, Pennsylvania.

10/26/06: Re-soldered bad solder joints at the left coin switch (o6) and the ramp entrance switch (40).

11/07/06: New pair of matched locks.

02/04/07: Rebuilt high-voltage section of the power supply. All the displays suddenly died and I determined that I lost -100 volts. As usual I turned to the repair manuals at Look under the display section of the System 11 manuals. Once I got the power supply board out of the machine I determined that the 39k resistor R4 failed, but by then I had already got a complete rebuilt kit from Great Plains Electrinics ( I replaced all the components in the high-voltage section. The new set of components outputs about +/-91 volts as opposed to the original +/- 100 volts. The displays are a bit dimmer, however, their life span should be considerably increased. While I was at it I also replaced the big +5 volt filter cap.


Before (left) and after showing all new high-voltage components.


The original high-voltage output transistors are no longer available and the replacements have a different pin-out. The leads need to be crossed as shown. This only applies to the D-8345 power supplies found in sys-11 and sys-11a games.

02/11/07: Added remote battery backup. Instead of permanently soldering some sort of remote battery setup to the CPU board I made battery place-holders from 1/2 inch dowel. This method requires no board modifications. And no connectors are needed between the board and the battery pack. The battery pack is from Great Plains Electronics. I like that the pack is fully enclosed. I don't like that it has an integral ON/OFF switch. I set the switch to ON and put a blob of silicone caulk over it. The battery wires are mounted to an end of each dowel with a screw and crimp terminal. The screw head becomes the "battery terminal". Don't forget to account for the height of the screw head when figuring the length of the dowel. Also shown is a plastic tool I got from Home Depot. The tool is for pulling large inline fuses, but is also great for pulling AA batteries.


Battery place-holders and remote battery pack. Note the blob of silicone over the battery pack switch.

The CPU board shows how each battery must be oriented, but does not show the location of +4.5 volts. Before removing the old batteries I used my volt meter to confirm that the lower-left terminal of the battery holder is +4.5 volts. The orientation shown here is correct for most System-11 CPU boards. Grand Lizard is at least one exception. Grand Lizard and the previous System-9 CPU boards (along with their battery holders) are oriented 180 degrees from that shown here.


Dowel sticks in place.

01/15/12 - Battery Pack Update: I rewired all my remote battery packs with 8' leads. Instead of placing the battery pack in the head, I drop it down into the body and place it next to the cash box. Opening the coin door is easier than opening the head. The idea is that I'll be better motivated to replace the batteries more often.


Remote battery packs with 8' leads. Scruffy gives each assembly a quality control check.

03/18/12: New playfield glass. New legs, bolts and levelers. Replaced stripped-out leg bolt plate at left rear corner.

03/24/12: Installed standard-keyed (751) lock on coin door.

12/15/16: Installed new CPR mirrored backglass in place of the original translite.


CPR mirrored backglass.

02/20/17: Added fuses to the AC sides of the solenoid and lamp matrix rectifiers. This modification is generally recommended for System-11 and System-11A games prior to the advent of the auxiliary power driver board found in System-11B and later games. The fuse modification potentially protects the game from shorted rectifiers.


8 amp slow-blow fuses added to the AC sides of the solenoid (top) and lamp matrix rectifiers.

12/30/17: Fixed right lane change switch. The non-banded side of the diode needed to be soldered back onto the switch terminal. This switch hasn't worked properly for years. Not sure why it took me so long to get around to it.


Right lane change switch.

I also replaced the old shooter rod spring with a new softer spring. My Pin*bot is somewhat unique in that it has an original unbroken vortex ramp. I always thought the shooter rod spring in this game was too stiff and endangering the ramp. The problem is non-pinball visitors who just whale on the shooter without realizing there's a skill shot. But I haven't found a definitive reference for comparing the various spring colors. The old spring was a cut down piece of brown or purple and was pretty stiff. The softest spring I had on hand was green which is what I used. I believe that Pin*bot should have a blue spring. But some sources list blue as stiff while others list blue as soft. I think I'll have to buy a broader assortment of colors and see for myself.


New green shooter rod spring.

05/19/18: The drop targets were sluggishly resetting so I cleaned the plunger and coil sleeve. In fact, this whole game is due for a good teardown and cleaning. I also noticed the remains of the upper left eject shield in the bottom of the cabinet. Time for new eject shields (part 03-9101-9). For now I found a old spare in my scrap box.


Busted eject shield replaced with a less busted eject shield.