Pressing a flipper button only lifts the flipper weakly and holds it; there is no strong flip. All three-lug flipper coils on the game behave the same way.

Flippers hold up but will not flip: corroded EOS switches

Cause: On these flippers the high-power winding is fed through the normally closed end-of-stroke (EOS) switch. If the EOS contacts are corroded they do not conduct even though they look closed, so only the hold winding gets power.

Checks

• Check that the EOS switches are closed with the flipper at rest.
• As a quick test, jumper across an EOS switch for a moment and press the button: if the flipper now fires at full power, the switch contacts are the fault.

Fix

• Clean or replace the corroded EOS switch contacts and set the gap so they open only at the end of the stroke.
• Remove any test jumper: running the power winding without the EOS switch will overheat the coil.

Systems

• Gottlieb System 3

Games

• Big House

Related tips

• Lights Camera Action: new upper flipper coil blows the main fuse: lugs wired wrong
• Gottlieb large flipper coils by wrapper colour
• Flipper weak toward the tip after a rebuild: EOS opening too early

Source: Pinball Repair help group!! (Facebook group)