[mitmaks]

when changing brake pads on discs, how would I go about getting calipers to back off to allow new pads, would it be ok to unscew bleeder nut and press them in or that would get air into system

[KULTULZ]

Originally Posted by mitmaks

when changing brake pads on discs, how would I go about getting calipers to back off to allow new pads, would it be ok to unscew bleeder nut and press them in or that would get air into system

You just described the correct way as not to force contaminated brake fluid back into the system. But it will usually require bleeding the calipers.

You can also use a syringe to remove brake fluid from the master cylinder reservoir as when you push the pistons back into the calipers, the displaced fluid will go back into the reservoir.

Press the pistons back into the bores with an old brake pad and large c-clamp. Mount new pads and calipers, press the brake pedal several times to push the pistons back out and refill reservoir.

[nosaj122081]

You shouldn't need to open the bleeder valve, just use a big C-clamp like the other poster mentioned and press it back in, not too hard... Take the lid off the MC and have someone watch, I've never had it overflow from new pads, but it could.

Oh yeah, you're not doin' this on some kinda new car are ya? Some late models that have rear discs and use the caliper as the e-brake you gotta screw back in, kinda a PITA.

[scot]

Open the bleeder screw, and connect a vinyl tube which empties into a container, so that the dirty/old fluid will exit into the container.
You want to replace the old with the new fluid. Add new brake fluid to the master cylinder as you go.

[Siggy_Freud]

Originally Posted by scrot

Open the bleeder screw, and connect a vinyl tube which empties into a container, so that the dirty/old fluid will exit into the container.
You want to replace the old with the new fluid. Add new brake fluid to the master cylinder as you go.

If you do it this way why not prime the tube going from the bleeder valve to the container with fluid. Also put some fluid into the container. This will allow you to keep air out of the lines and from having to bleed the system.

However if it were me, Id just pop the top to the master cylinder and use a c-clamp like was mentioned. Never had trouble with this method.