Lubricate almost nothing

Nearly every part runs dry; over-oiling does far more harm than none. Only metal-on-metal pivots such as ball eject and slingshot hinges may get a drop of light oil. Never use WD-40.

Systems

• Bally MPU AS-2518-17
• Bally MPU AS-2518-35
• Stern MPU-100
• Stern MPU-200

Related tips

• Where to lubricate and where not to

Source: Repairing Bally Electronic Pinball Games from 1977 to 1985, Part One, Clay Harrell (pinrepair.com)