Well my front brakes started to make a nasty grinding noise. Its been going on for some months now, but as the car went through its MOT and an annual service with no problems within that time, neither brake pads nor discs were mentioned, I haven't been too concerned. However, its obviously annoying and passengers are noticing. It will do no harm to change the brakes, and checking shows that discs are recommended for change very 30k miles... I have no knowledge of mine ever having been changed and as I'm now at 120k, I'm guessing this is likely to be the problem! I bought new Eicher pads and discs which seemed very reasonably priced.
First step- jack up the car and remove the road wheel. The pads are visible clipped into the caliper with a wire spring. Lever this out with a screwdriver but hold it at the same time with a pair of pliers to prevent it going anywhere.
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| Clip visible on outside of caliper |
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| Remove clip with a screwdriver and pull it out |
The caliper is held to a bracket which is itself held onto the front hub. The caliper retaining screws are hidden beneath plastic caps at the rear of the caliper. Lever the plastic caps out...
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| Plastic caps removed from rear |
... and use a 7mm Allen key socket on a short extn bar to unscrew- they dont need to come out completely to remove the caliper- just unscrew out of the bracket but if there are corroded then that may need to be withdrawn and cleand, refit with antisieze
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| using the 7mm Allen key to unscrew the caliper mounting bolts. |
When both the bolts are released, the caliper can be wangled off the disc bringing the pads with it- front pad may fall out in the process.
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| Caliper removed, front pad came out. |
Do not let the caliper hang on its flexible pipe, I suspend it with a bungy running through the suspn spring and down to clip onto the steering tie rod.
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| Suspending the caliper using a bungy |
Remove the front pad- noting orientation although it seems hard to get this wrong in this car.
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| orientation of front pad. |
This leaves the bracket on the hub and this has to come off before the disc can be swapped. In my case the disc was clearly worn leaving a prominent ridge around the rim. This was contacting the metal edge of the pads as the pad material wears down and thus accounts for the grinding noise on braking.
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| Bracket left in place when caliper removed |
The bracket is held on by 2 13mm bolts again on the inside of the bracket
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| Position of bracket mounting bolt indicated by grubby finger. |
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| Bracket mounting bolts loosened- not fully removed. |
Once these two bolts are released, the bracket comes away
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| Bracket slips off the hub. |
... and the disc then lifts off the wheel studs.
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| Disc removed |
The next step is to compress the piston to make room for the new pads. This will push fluid back into the system so you can remove some brake fluid from the master cylinder to make room for this. However, I understand that pushing fluid backwards might do damage to the seals in the master cylinder so an alternative is to clamp the flexible and slacken the bleed nipple. Fluid is then disoplaced through the nipple rather than backwards through the MC. Use a flexible pipe (preferably with a one way valve as in bleeding) to direct the fluid into a suitable container... you will need three or four hands or a range of suitably sized supports to stand containers as you are also holding the caliper and whatever you are using to push the piston back.
I used this cheap tool from ebay- fantastically simple! Leave the rear pad in position and use this tool to press the pad (and the piston behind it) into the caliper against the front supports. Others use a simple G clamp although this could damage the caliper. This clamp is much safer.
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| Really neat piston clamp compresses piston with no risk of damage. |
Close the bleed nipple, and remove the piston clamp and pipe clamp. The rear pad has clips on the back to hold it inside the piston; it just pulls out.
Clean the packing grease off the new disc and slip it onto the hub.
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| New disc on- piston clamp not yet off. |
Refitting
Refitting is as they say the reverse of disassembly. It was surprisingly straight forward. Sorry about the lack of pictures but I was lost in the excitement of the rebuild!- Refit the bracket to the hub.
- Put a smear of copper grease onto the back of the pads (take care not to get any on the pads or discs themselves) to help prevent squeal. My new pads had anti squeal shims already in place.
- Clip the new rear pad inside the the piston and hold the front pad in position. Offer the assembly up to the new disc and slide it over the rim and into position making sure the orientation is correct and the wings of the pad fit into the slots on the bracket.
- Refit the caliper retaining bolts; it is a bit tricky to line up these bolts as visibility is limited, but its possible with a bit of perseverance. Screw them in to hold the caliper in place.
- Check the torque setting of all bolts.
- Refit the plastic caps followed by the roadwheel... do not forget to remove the bungy strap!
- Pump the brakes and check that the pedal firms up
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