How to change Discs and Pads- by Speedy

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Categories: MR2 Mk1 Articles -> Brakes

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[url=https://imoc.co.uk/app.php/kb/viewarticle?a=135&sid=e0b9a3620aa8ddd05c9e30a1960f63a4]Knowledge Base - How to change Discs and Pads- by Speedy[/url]

So, to replace front disks and pads, you will need the following :
- A 12 mm socket for the caliper bolts
- A 17 mm socket for the torque plate bolts
- Ratchet for above sockets
- Breaker bar for above sockets
- A 8 mm spanner for the bleed nipples (if standard)
- A way of restricting the flow of brake fluid in the pipe (small g-clamp or special tool)
- Brake fluid
- Bleed kit (or tubing and knowledge of how to use it!)
- Something to support the caliper (we use an axle stand)
- Caliper wind-back tool
- Your wheel brace
- Your fave way of lifting and supporting the front of the car
- Chock
- Some lithium grease for the pins (optional)
- Some copper grease for between the wheel and disk (optional)

Chock the car, and crack off (snigger) the wheel nuts, then jack up, and support the car using your fave method.
Remove a wheel (we did passenger side first, since for bleeding purposes, that one is furthest away from the cylinder). It can be useful to put a couple of wheelnuts back onto the disk to hold it in place.
Begin to remove the caliper pin bolts - these are the ones which go through the little rubber boots. You might need your breaker tool for this, since they can get stuck on.
Remove caliper bolts - one of ours came out complete with the pin, since they were heat-treated together. If you want to do a complete job (or you have a \'sticky\' caliper), you can work the pin out if it doesn\'t come out, and re-grease it with your lithium grease.
Lift the caliper off the pads - this can be tricky, and you\'ll probably require some grunt to work the caliper forwards and backwards to get it off the pads. Since we were losing our disks (and our calipers are a b*tch), we\'ve used the end of the wheel brace to lever it up - do that at your own risk!!
Once the caliper is free, put it on an axle stand to support it - the aim is to not stretch the brake line.
There are two little springs which slot into the top of the pads - just lift them out (they might need a little wiggle to get them moving), we didn\'t get any replacements for these, so be careful not to break them!
If you aren\'t replacing the disk (just the pads), you can probably get away with not removing the torque plate, and just pull the pads away from the disk. They are held in place by little springs, so it\'ll probably require a little wiggling to get them out.
Now you need to remove the torque plate which is the assembly which the pads sit in. It\'s retained by two 17mm bolts on the back of the hub - again, you might well need a breaker device for this.
Wiggle the disk off the hub, and replace with new disk, again, you might find it useful to stick a couple of wheelnuts on to hold the disk in place while you work around it.
Replace the pads in the torque plate - I found it easier to put the rear pad back in the plate before re-attaching the plate to the car. It\'s a little fiddly to get the holes lined up again. Gently tighten up the bolts (just incase something goes wrong and you have to take it off again).
Replace the front pad in the torque plate - should just slide and slot into place.
Replace the little springs on the top of the pads, again, should just slot into place.
Disk & pad replacement complete, it\'s time to sort out the caliper.
Restrict the flow of brake fluid in the pipe. Careful not to pinch the line too tightly.
Place your windback tool in the caliper, and take up the slack.
Attach your bleed kit to the bleed n1pple, and open the n1pple.
Wind back the caliper gently and slowley. Brake fluid should be coming out of the bleed n1pple, if it isn\'t then check that your bleed n1pple is open. Just wind it back as far as it needs to. For us, this was so the piston was flush with the body of the caliper.
Close the bleed n1pple and remove the bleed kit.
Now, put the caliper back over the pads. You might find that now the disk+pads width is greater, you have to push the pins back in the rubber boots to get enough clearance - gently does it.
Put the top caliper retaining bolt & pin (if you removed it - possibly grease with some lithium grease) back in, and then the bottom one. Tighten up.
Check that there isn\'t excessive binding - i.e. you can spin the disk quite freely. If there is excessive binding, then you might have not wound the piston in far enough, or there is something else wrong.
Now you\'ll need to bleed the brake to make sure you get rid of any air which has made it\'s way into the system. Remember to check the level in the master cylinder, and top up if necessary.
Tighten up all the bolts, torque plate and caliper pin bolts.
Put a little dab of copper grease around the base of the studs - this will help the wheel come off the hub if/when you have to take it off again.
Put the wheel back on again - all done!!

Now, just do it all again on the other side!