Test rig for brake cylinders
Posted: Wed Oct 22, 2025 9:14 pm
I recently replaced a rear slave cylinder because I was also doing the hub seals and new brake shoes, but the one I took off (a Delphi) didn't look too bad. I was thinking of a way of testing it, and possibly others, off of the car, and also found a spare Lockheed master cylinder in the garage, which i also wanted to test, as it had been sitting in a drawer for years!
So, I found a length of suitable brake pipe, joined the two together with a bleed nipple, topped up the master cylinder with fresh brake fluid, bled the 'system' then tested the pair out by using a suitable sized long bolt to activate the master, while pressing it against the garage wall, and looking for movement at the slave - sure enough, the piston moved out. To get it to go back in again, one simply pushes the handbrake lever on the slave cylinder against the piston to force it back inwards.
Thought I'd share, in case anyone is interested. You could, of course, attach the master cylinder to a suitable base and maybe add a lever to operate it, for a more refined test rig, but it did the job as pictured.
So, I found a length of suitable brake pipe, joined the two together with a bleed nipple, topped up the master cylinder with fresh brake fluid, bled the 'system' then tested the pair out by using a suitable sized long bolt to activate the master, while pressing it against the garage wall, and looking for movement at the slave - sure enough, the piston moved out. To get it to go back in again, one simply pushes the handbrake lever on the slave cylinder against the piston to force it back inwards.
Thought I'd share, in case anyone is interested. You could, of course, attach the master cylinder to a suitable base and maybe add a lever to operate it, for a more refined test rig, but it did the job as pictured.