I'll admit that i know little when it comes to the air system of my bus but i understand the core principals. The service door on our bus uses an electric rocker switch in a neutral position, up activates one side of the cylinder of our door (open) and it returns to neutral, down activates the other side of the cylinder (closed) and returns to neutral.
A short time ago i noticed the sound of air leaking when i shut the door and traced the sound to what I can best describe as a plastic screw plug that can be hand tightened so i snugged it i and the sound stopped. Until last night.
I tried tightening it a bit more with a set of needle nose to grip better, no luck. Tired thread tape, no luck. I even tried pulling the plug from the open side and still no luck. I've not got a lot of clearance on the back side to see what I'm looking at but I'm afraid I've got a crack. Figured I'd seek advice from those more experienced to see if anyone else ran into a similar problem.
Also it looks like the district cut some writing and did a bit of splicing to the mechanism, if anyone is able to explain that i would be very grateful.Attachment 5152820201129_174828.jpg20201120_125430.jpg