Parking break release uses secondary tank only

Truck 2011 Freightliner fm2
Cummins isc 260
My parking break knob broke off with the pin connected to it. I replaced parking break valve. Connected air hoses same to same color (red, blue, black, green). When i release parking break, only secondary tank is draining noticibly. Main drains very slowly if i repeat pull and release. Secondary drains 5 times faster. No air loss detected if i drive or fully parked. Replaced parking break valve again, same problem. Second parking break valve is the same as 1st, sold by premier trucks in Mississauga. Please help.