Troubleshooting - Tandem Master Cylinder with No Fluid/No Pressure to the Rear
Common complaints to our tech line involve no pressure to the rear brake lines. With a dual circuit/tandem M/C this issue has a common cause - the rear piston not fully returning to its proper resting position. Customers often think they have a defective M/C but that’s not it. For the M/C to build pressure properly, the piston's primary seal must retract past the compensating port, and the rear of the piston rest on the snap ring.