During the landing roll, the pilot was unable to maintain directional control and the airplane swerved side-to side before going off the right side of the runway. The pilot said overhauled brake assemblies had been installed before the accident. He complained that the brakes felt “spongy” and the pedals went “almost to the floor, requiring two or three additional pumps for a hard pedal.” He was told that this was “normal” since the airplane was not equipped with power brakes or anti-skid. The brakes were removed and sent to the overhaul facility. They found that both brake assemblies each had one return mechanism binding. The return mechanism had a self adjusting friction bushing meant to slip along the return pin at a predetermined spring pressure. As pressure was applied to the brake, the pressure plate extended toward the number one rotor, pulling the return pins through the swage and tube assemblies and compressing the return springs. Although the swage should move through the tube, one swage on each brake was not moving freely. The brake travel went further than normal because “normal travel” was never set. Probable Cause: mechanical binding of the normal brake system, rendering directional control impossible. Contributing factors were the improper overhaul, inadequate quality control procedures by the overhaul facility, and the rough terrain.