QR1 and pressure regulator valve repairs

I discovered a couple of air leaks after running the bus a week ago.  Ordered parts and the arrived Friday.  So Saturday I worked on the bus attempting to fix the air leaks.  First is this quick release valve which, in this case, is part of the parking brake system.  It resided up front in the spare tire compartment behind the bumper.  Luke at U.S. Coach sent me the rebuild kit which consisted of a diaphragm and a gasket.  Other than laying the the compartment on your back removing the QR1 valve was not difficult nor was dismantling it and replacing the two parts. However, in reading the maintenance manual it mentions a spring and diaphragm seat and my valve clearly did not have these parts.  After I reinstalled the valve I aired up the system and it STILL leaks out the exhaust port with the parking brake applied.  Not sure what my next step is going to be.  I wonder if I have a leak somewhere else in the parking brake system and it just happens to leak back through the exhaust port of the QR1 valve.  I'm still researching.


After finishing the QR1 valve, I removed, rebuilt, and reinstalled the pressure regulator for the blower belt tensioner.  Here is a picture of it NOT blowing bubbles after the rebuild.  Only problem is, it STILL leaks too, just not as bad.  No nest of bubbles, just leaking out the tiny weep hole in the back.  I am researching that one too, but feel that the problem may be a leaking tensioning air cylinder and it comes out the weep hole.  Hopefully I can update with the fix soon.  The regulator is at the top of the picture and the air cylinder on the right side.