This is my first time ever installing a brake system. I’ve got a '50 3100. I converted the front brakes to the disc set up from CPP. Added the dual master cylinder with no power under the floorboard. Stayed with the original Huck brakes on the rear. Both the rear brakes were rebuilt. I have the master cylinder plumbed thru a combination valve and installed a 2 lb residual valve on the front to prevent backflow. I installed all new lines and fittings. I bench bled the master and installed in the truck. The rear brakes bled fine and pumped right up. The front disc brakes are another story. When bleeding I can get little or no pressure out of either caliper. I Bench bled the master again just to make sure. Next I plugged the outlet ports on the master cylinder and checked the pedal. Pedal was solid so master cylinder is fine. I plugged just the front & tested rears. Great pedal, no problems there. Connected to just the fronts and pedal goes to the floor. Installed a couple of speed bleeders. Can get weak fluid pressure out of right side and nothing on left. I removed the left side brake line and get some fluid out. Reinstalled line. Tried bleeding again and nothing on left side. Started at the master and cracked fittings and can get fluid pressure right to right side caliper. Still nothing out the bleeder on left. Cannot find any leaks or blockages. What am I missing here?

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