check the gapping on the open contacts. sounds like one of them is not adjusted correctly.

Hi Azfalconfixer
great - You have the schematics. Want to show the snippet with "bumper-action" ?
I show my Gottlieb Orbit --- the switches below the "skirt (?) of left and the right bumper" activate the B-Relay --- and the B-Relay actuates BOTH Bumper-Coils - BOTH bumpers fire --- BOTH bumpers must open their End-Of-Stroke-Switch so the B-Relay quits pulling --- and in YOUR pin ? Greetings Rolf

0Orbit-Work-08 (resized).jpg

Hi Azfalconfixer
when You put some insulation into the E.O.S.-Switch to keep it permanently open: Your pin is fully running ? If "Yes" - want to do some documentation (explanation of the mystery and the work-around solution) - and keep the documentation in the pin (?) (((mystery stays mystery)))

I feel a bit uneasy - asking questions You most likely already have checked ...
When the ball rolls to "left" bumper - BOTH bumpers fire ?
When the ball rolls to "right" bumper - BOTH bumpers fire ?
The strength (power) of firing is the same (both bumpers fire heavy) ?
Have the pin toggled off and the main power cord unplugged (Safety Reasons) --- manually actuate the "good" bumper and watch the opening of the E.O.S.-Switch. Then manually actuate the "bad" bumper and watch the opening of the E.O.S.-Switch - Same ? Clear, good opening ?

Timing (?) --- the two E.O.S.-Switches should open exactly at the same moment in time --- the one "opening later" carries the load (current flowing to keep the B-Relay pulling) - its contact points may wear due to sparks on the opening switch.

(((I would prefer: ONE Bumper - ONE Relay activating this bumper --- ANOTHER - ANOTHER --- THIRD - THIRD etc. Maybe the manufacturer wanted to save money by using less relays (?) )))
Greetings Rolf