Front Brake Pads

[c5banger]

Hiya, I need to replace my front brake pads on my 51 plate C5. Do i need a special tool for winding the pistons back in, & where can i buy said tool?? Thanks for any advice. Pete. :wacko:

[paul.h]

A car accessory shop will sell a special tool, has a couple of prongs on it to engage with the piston and such as Machine Mart sell complete kits to cover many cars. The pistons on the 2 sides turn in opposite directions.

[paul.h]

A car accessory shop will sell a special tool, has a couple of prongs on it to engage with the piston and such as Machine Mart sell complete kits to cover many cars. The pistons on the 2 sides turn in opposite directions. There is a pinned note on the problems and fixes pages on changing the pads, it mentions removing a pin but there is not one, only the lower guide bolt to remove and then pivot the caliper up. Pad replacement is covered in the Haynes manual. The slots on the piston have to line up with a raised bit on the caliper body so the pads go in correctly. I prefer to wind in the pistons with the bleed nipple undone to release the excess brake fluid in to a container to avoid possible problems with the master cylinder, if not check the fluid level in the reservoir does not go too high. Refit the handbrake cable to the caliper after the footbrake has been used a few times to push the piston out to the pads.

 

Job is something like:

Raise car to max height on suspension, chock rear wheels, jack up one front side, fit axle stand, remove wheel, check thickness of brake disc is not below minimum, turn steering to side jacked up so more room for working, release handbrake, pull off pad wear sensor wires at the top, thread lower one through bottom of caliper (may break plastic doing this), unhook handbrake cable from caliper and pull back, undo lower caliper guide bolt, pivot caliper up and tie back, remove pads, clean everything up, clean brake disc with fine emery paper to remove glaze and remove rust from edges and wipe clean (brake cleaner), wind in piston (right side anti-clockwise, left side clockwise) making sure the rubber boot does not turn, check new pads fit, apply a bit of copper grease to the pad and mounting bracket contact surfaces and the backs of the pads (but not the pad friction or brake disc surfaces), fit pads, lower caliper, fit guide bolt (31 Nm), fit wear sensor wires, push brake pedal to push piston against the pads, refit handbrake cable, clean hub and if alloy wheels apply a smear of copper grease, check tyre for damage/stones/nails/etc then clean wheel/hub contact surface and refit wheel.

[Johndouglas]

It isn't essential to purchase a tool to wind the pistons.   If you have a length of 8mm steel rod, it can be bent into a 'U' shape which will do the job.   Place the ends into the piston end and use a tommy bar to help with the turning.

[c5banger]

A car accessory shop will sell a special tool, has a couple of prongs on it to engage with the piston and such as Machine Mart sell complete kits to cover many cars. The pistons on the 2 sides turn in opposite directions.

Thanks Paul H.

[c5banger]

It isn't essential to purchase a tool to wind the pistons.   If you have a length of 8mm steel rod, it can be bent into a 'U' shape which will do the job.   Place the ends into the piston end and use a tommy bar to help with the turning.

Cheers Johndouglas.  To be honest i didn't expect any replies as i had trawled through page after page looking for tips. All the posts seemed to be ancient, as if no-one used these pages anymore. :rolleyes:

[Johndouglas]

When you get around to doing the job, bear in mind that each side winds in in a different direction.   Offside goes back anticlockwise, nearside clockwise. 

[DaveHerns]

You can buy a "Cube" with different spacing prongs to suit different calipers .This fits a 3/8" socket extension .You need to push in while turning. It's not hard , I've done it!

[c5banger]

Job done. Didn't want to jemmy my frozen garage doors open, then sit in snow on the street doing the job. Booked it into a local garage. Turned out i needed discs as well, kinda suspected so. Hour n a quarter in garage. Would have took me a lot longer & my local parts shop would have prob sold me wrong discs, LOL Cheers.

[coastline taxis]

A 3/8th ratchet and extension fit into the center of the piston and can be used to wind both sides back