Front Brake Pad change

[roton600]

Hi,

Im after some advice...i am going to be changing my front discs and pads on a 2000 406 HDi estate, after talking to someone at work they said that when you push the caliper piston back that you need to open the bleed screw on the caliper to prevent the seal in the master cyclinder flipping back on itself? I have never done this on any other car i have changed pads before, just opened the master cyclinder cap and put rag around to catch any excess brake fluid.

Has anyone heard of this before or done this? As would obviously prefer not to do it as then will have to bleed the brakes.

[mandelbug]

All I do is take the reservoir top off the master cylinder to allow the piston to be pressed back easily

[steve_earwig]

I thought there was a valve in the piston to let the fluid back (or the brakes wouldn't release )

[roton600]

Thanks for the quick replies, thought as much....will do it as i normally do...just take the master cyclinder cap off and push the caliper back slowly.

[jasper5]

Opening the bleed screw was for the early 1970's vauxhalls, if you didn't open the bleed screw before pushing back the pistons you destroyed the master cylinder.

[omega]

dont you have to wind the pistons back in if it has abs?,im sure also ive read somewhere that
theres a pin that can break?
not sure about this so hopefully someone can confirm or not

[mandelbug]

Rears are usually wind back to accommodate the handbrake from memory. Fronts push in and out.

[steve_earwig]

Handbrakes are separate mechanical shoes (you thinking 407?)

[mandelbug]

On my Mk4 Golf and a couple other cars I have worked on, the rear calipers are wind back when the handbrake mechanism is in the caliper rather than being a drum brake on the inside of the disc. My 200 has a drum inside the disc (i.e. handbrake shoes) but the caliper pushes back on the rear.

[jasper5]

Makes no difference whether it's ABS or not.
Most rear calipers these days are wind back as most of them are the same caliper, Ford, Vauxhall, Peugeot, Citroen, Renault, Volvo, and several other including vans have wind back calipers.There are some that are electronic and can only be reset by using diagnostic machines (this includes fronts).Some handbrake mechanisms are electronic.
Some cars have to have the warning lights reset by diagnostic machine and I always replace the warning wires on BMW and suchlike.
Of course the 406 has drum handbrake and a caliper that pushes back, except the older ones.

[steve_earwig]

Some handbrake mechanisms are electronic.

And they're doing really well "follow that Passat!!"

Used to have to wind the front brakes in on my BXs, using a bar the right thickness, keep the pressure on... pain in the bum that was The first car I worked on where the mechanical handbrake worked through a hydraulic piston was... a Morris Minor

[jasper5]

Ah, the Morris Minor Those stupid trunnions that always used to strip their threads and dump the wheel on the ground

Have you ever worked on the Citroen 2CV? The handbrake was adjusted by undoing a locknut and turning a large eccentric nut, you locked up the brake then backed it off slightly.