Are there any secrets to bleeding the rear brake on a Techo. The rear brake did not work so I pulled the rear caliper and disassembled. Everything looked OK except the sealing surfaces where the bleeder valve seats. I reconditioned them. After assembly, I have tried the "suck method"...vacuum at the bleeder valve and pump method...pump, open valve, close valve, repeat....both get some (not alot) fluid to flow but the brake is still not operative. I can see the pads move but there is no braking action. Any suggestions?????