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Pinball machines contain potentially lethal voltage. Dangerous voltage may remain for a period even after it is unplugged. Repair should be left to properly trained personnel. Prior to opening a pinball machine, be certain to unplug it, then turn it on to insure that it was actually unplugged. It is recommended that the machine be allowed to sit several minutes to allow any remaining power to dissipate.

Getting started[edit]

Glossary of pinball terms

Pinball machine can be divided into two general areas, the playfield and the backbox. There are also two general categories of pinball machines, solid state (SS) and electro-mechanical (EM) machines. SS machines have digital displays that power up when the machine is turned on. EM machines use mechanical reels that spin to display the score.

Maintenance of SS and EM playfields are similar. However, the similarity ends there as EM machines use relays, motors and switches to run the game. SS machines rely on electronic circuit boards (PCB) to control the game.

There is a tremendous amount of information available on the Internet about pinball repair. One of the most complete websites is

The first step is to identify your pinball machine type and model. An excellent resource is the Internet Pinball Database. Look up your pinball machine on this database to determine what type it is. Find out the manufacturer and the type (Solid State Electronic or Electro-mechanical) and the year. If your machine is solid state, also note the MPU type. You can then use this information to identify the information you need to research at or other websites.

It is always helpful to have the operating and repair manuals. For older machines, this may be a single manual. For later machines, usually two or even three manuals may be needed. These manuals can usually be purchased at Steve Young's The Pinball Resource, Marco Specialties., or Mayfair Amusements. If your machine was manufactured by Stern, Sega or Data East, the manuals may be available from Stern Pinball, Inc.

Routine maintenance[edit]

Regular maintenance of a pinball machine can keep it running smoothly and maintain its resale value. Prior to starting, see the Caution above. The supplies suggested below are available from companies that supply pinball parts (see External links: Parts).

Supplies needed[edit]

Most maintenance can be accomplished with supplies found in local stores. Some materials may have to be ordered from pinball parts suppliers. The following parts may be needed (will vary depending on the machine):

  • Q-tips.
  • Isopropyl alcohol (91%). Do not use rubbing alcohol.
  • Screwdriver (Phillips and standard).
  • Needle-nose pliers.
  • Allen wrench set.
  • 400 grit sandpaper or flexstone (switch cleaning).
  • Nut driver set.
  • Multimeter (volt ohm meter).
  • Novus #2 cleaner
  • Treewax or Meguires Carnauba wax


The pinballs wear, get chipped and can contribute significantly to the playfield wear. It is recommended that pinballs be replaced regularly. New pinballs are inexpensive and can be obtained from the parts suppliers listed below.

The playfield[edit]

The condition of the playfield can determine the resale value of a machine. Additionally, dirt on the playfield can slow the play down. As an owner, a playfield is easy to maintain.

If you find it necessary to tilt up the playfield, it is recommended that you remove the pinball(s) first. Otherwise, raising the playfield may eject the pinball, which could damage the playfield or backglass. Removing the pinball can be simple on single ball machines or tricky on multiball games. For single pinball games, you may be able to reach in and remove the ball, or manually press the solenoid ball eject mechanism. For complex EM games, it may be easier to enter the service menu to eject the balls. Consult the repair or operating manual for the specific procedure.


The first step is to clean the playfield. Novus #1 and Novus #2 are recommended cleaners [1]. Plastic ramps can be cleaned with Novus plastic polish.

The playfield should be waxed regularly. Be certain to use real wax. Treewax and Meguires Carnauba wax are among those recommended. [2].


Check the flippers and other moving parts. Manually move them and make certain that they do not contact the playfield. If a flipper scrapes along the playfield, it will quickly wear through the surface, which will detract from its appearance and reduce the resale value. If necessary, readjust the connection to the flipper shaft, which can be accessed from under the playfield. Adjustment involves loosening the bolts that are connected to the shaft of the flipper, then raising the flipper so that it no longer touches the playfield while in motion. Then tighten the bolts while holding the flipper in the proper position.

Rubber rings[edit]

The rubber rings on the playfield dry out and crack. As they age, they slow down the play and detract from the appearance of the game. New sets can be purchased from pinball parts suppliers. Depending on the complexity of the game, replacement can be easy, requiring only a few hours, or exceedingly complex.

With older games, all that is generally necessary is to remove the playfield plastics using a nut driver and screwdriver. It is a good idea to take digital photographs of the playfield before you start with additional pictures during the disassembly. These pictures will help with reassembly.

Some parts suppliers will provide pictures with their rubber ring replacement kits. The location and size of the rings are also listed in the pinball manuals. The rings usually have raised mold markings on each which indicate their size the can help with determining their location.

Some machines were manufactured with black rubber rings. These look nice, but can contribute to dirt on the playfield. White rubber rings do not cause as much dirt as they age.

Games with ramps, either wire or plastic, are more complex to disassemble. Some games like White Water have four ramps that intertwine with each other. Disassembly and reassembly requires a great deal of patience and care.

While you have the machine apart to replace the rubber rings, it is a good idea to clean and wax the playfield.

Playfield Switches[edit]

Playfield switches control the scoring of the game. They can become dirty or bent and fail to activate scoring. Usually, all that is needed to fix the problem is cleaning or adjustment.[3]

The first step is to test the switches. The easiest method is to open up the game, remove the cover glass and then manually manipulate the switches. This can be accomplished with a pinball or a push with your finger. If it works, leave it alone.

If several switches do not operate, look at the switch matrix in the operating or repair manual. If the non-operating switches fall in the same row or column, then it may be a problem with the wiring or the circuit board.

The cleaning procedure will be different if you have and EM or a SS game.

Cleaning EM playfield switches[edit]

With EM games, the full power to fire a relay or solenoid travels through the playfield switches. To clean these switches, 400 grit sandpaper or a flexstone file is recommended[4].

The switches that power the flippers and those at the flipper switches (EOS or end of stroke) handle higher currents and are designed differently. They can be filed with a standard metal file or they may need to be replaced. Worn or dirty flipper and EOS switches will lead to weak or non-functioning flippers.

In addition to the switches located under the playfield and the flipper switches, EM games have switches in the backbox and, usually in the cabinet under the playfield. Dirt or wear on these switches can lead to malfunctioning games.

Cleaning SS switches[edit]

Leaf Switches[edit]

SS machine switches work the same way as EM switches, except these switches have only low voltage (5 volts) flowing through them. That means they are less likely to be damaged by arcing and high current.

Most of these switches have gold or silver contacts and should never be cleaned with sandpaper or files[5]. Instead, use a non-abrasive cleaner such as a piece of cardboard or business card. Another method is to use a q-tip and a small amount of isopropyl alcohol (not rubbing alcohol) on the q-tip. Caution, alcohol is flammable and overuse can lead to a fire.

The only switches in a SS game that may require filing or sanding are the EOS switches located on the flipper solenoid. For older SS games, the full current flows through these switches and they need to be cleaned following the method described under Cleaning EM switches. The only exception is machines controlled by Fliptronics circuits[[6]]. Fliptronics EOS switches handle low voltages and should never be cleaned with sandpaper or other abrasives. They must be cleaned following the same procedure outlined for SS leaf switches. Fliptronics switches can be easily identified because they are not touching (normally open) when the flipper is not in use.


Microswitches are enclosed and cannot be cleaned. If they malfunction, they may need to be physically adjusted or replaced.

Opto Switches[edit]

Opto switches have a LED (transmitter) and a receiver. It is possible to physically adjust these switches. They may be cleaned with a q-tip and isopropyl alcohol. However, when they malfunction it is usually a sign that they need to be replaced.

Magnetic Switches[edit]

Magnetic switches act by sensing the presence of the metal pinball. They are sealed and cannot be cleaned. Malfunction usually means that the switch has failed or there is a problem with the wiring or the circuitry.


All solid state (SS) machines have batteries to maintain the machine memory. The memory retains settings and other information such as the high scores. Batteries will leak with time and when they leak, they can destroy the circuit board (PCB) around and below the location of the batteries. It is important to replace the batteries with fresh ones annually.

Some pinball machines have been modified so that the battery pack has been moved off the circuit board, usually to the bottom of the back box. Other machines have been modified so that the batteries have been replaced with a large capacitor and these do not require routine maintenance.

Electro-mechanical pinball machines do not have batteries.