HOWTO: Replace Rear Discs & Pads (Octy Mk1)

[thesquiff]

Replacing rear discs and pads - Skoda Octavia Mk1 (pre-facelift) 1.9TDI 110

So it's a fairly straight forward job but I though I'd take a few pics along the way in the hope it might help someone else out at some point.

Firstly a disclaimer: I am not a qualified mechanic - my way of doing this may not be correct, or best practice. Make up your own mind - if you're not sure, ask a qualified mechanic. We are talking about brakes after all - and they're quite important.

These instructions are for doing one wheel, obviously any brake work needs to be replicated on the other side, i.e. if you replace brakes pads, you must do both sides, and if you replace the discs, you must do discs and pads on both sides.

Tools you will need:

Wheel bolt wrench

1/2" socket

5/8" spanner

Copper grease

Caliper rewind tool

Lump hammer

Philips head screwdriver (medium size)

string or long cable ties

axle stand

pipette & clean glass jar

Here goes:

Step 1: Remove road wheel and jack up rear corner.

Not going to go into detail on this, but remember to use the correct jacking points. Add extra support with an axle stand. Chock the front wheels.

I had an absolute mare getting my rear alloys off. Lots of penetrating fluid and a very big hammer required.

Step 2: Remove the two caliper bolts.

Release the handbrake (make sure you have the front wheels chocked OK).

I needed a 1/2" socket and a 5/8" spanner to undo the bolts. Use the spanner to hold the nut in place and the socket to undo the bolt. The lower bolt gets fouled slightly by the handbrake cable so I used a short extension.

Step 3: Withdraw the Caliper from the Disc

I found on one side the caliper came away really easily, on the other it needed some help from a friendly hammer.

We don't want to leave the caliper dangling from the brake hose so tie it up with string or a cable tie.

Step 4: Remove the brake pads and their clips

The pads should be quite loose now so should just pull out or fall out.

Step 5: Remove the discs from the hub.

You'll need to undo the locating screw, which will be a phillips head. Hopefully the kind soul who put it there will have smothered it in copper grease so it will come out easily. (If you've got one really foobared or the head breaks off you may have to resort to drilling it out).

Once the locating screw if out then the disc should come away from the hub. If it's a bit stubborn, use a lump hammer on it.

Step 6: Rewind the caliper.

Undo the top of the brake fluid reservoir before doing this and if it looks overfull then it might be wise to pippette a bit out into a glass jar so the reservoir doesn't overflow. Don't get any on your paintwork - it's corrosive as hell.

You really need the right tool to rewind the calper. People will say you can do it with funny shaped pliers but you risk making a mess of the protective rubbers and it will take ages.

I've had a Laser rewind tool from Halfords (I think it was about £20) for a few years so I dug that out.

The caliper was a bit stubborn to turn back to begin with but all that was needed was a bit of perseverance. The caliper needs to be wound in the whole way if doing both discs and pads to get enough clearance. It might take 5 minutes or so. Don't rush it too much as you don't want the tool to slip off and damage the rubbers.

On one caliper I couldn't get it to move at all to start with so used a small g-cramp to compress the face of the piston into the body slightly - this seemed to free it up.

Step 7: Insert New Disc

I've known new discs come coated in grease before to stop them going rusty so if you have any doubt, give them a good wash with soapy water. (Fairy liquid seems to work well). Mine came from the dealer and I don't think the really needed washing but I did anyway.

Fantastic picture coming up!

The new disc should locate easily into place. Remember to reinsert the locating screw. Make sure it has plenty of copper grease on it so you can remove it easily next time. A bit of copper grease on the hub should stop the brake disc welding itself on too much.

Step 8: Fit the new pads either side of the disc.

First you'll need to fit new clips. Depending on how corroded your caliper is, you might need to bend the lugs every so slightly to get them into place.

The pads should fit easily either side of the disc.

Step 9: Refit the caliper

Cut off the cable tie / string supporting the caliper and move it back into place around the brake pads. You should fit new bolts when refitting (some were supplied in the box of brake pads from the dealer for me).

1/2" socket and 5/8" spanner required again to do up the bolts. Do them good and tight, but don't go mad.

Don't forget to do up your brake fluid reservoir. Any excess you pipetted out at the start, you can put back in so long as it's been kept absolutely clean. Any dirt or water is not good news - don't put it back in.

Step 10: Refit Road Wheel

Probably a good idea to put the wheel back on. If you had problems getting the wheel off in the first place you might want to put a bit of copper grease in strategic places. Don't forget to torque the bolts correctly. (Well actually I've never torqued them correctly, I just do them up to a tightness I'm happy with and I've never had a problem yet - but it's up to you :-))

That's it, job done. Pump the brake pedal until pressure returns. Go *carefully* for a test drive. Remember it will take time for the new brakes to bed in an optimum brake performance to return.

Edited 6 September, 2012 by thesquiff

[Bowders1]

great guide buddy....

[Raf_]

Great guide m8, thought you're ment to clean the face of the hub before fitting the new discs tho?

Sent from my Galaxy S2 not a Crapple!

[thesquiff]

Great guide m8, thought you're ment to clean the face of the hub before fitting the new discs tho?

Sent from my Galaxy S2 not a Crapple!

Yeah that would sound sensible. I'm only a basic DIYer so always happy to gather advice from others.

[ian996]

Great guide bud. Mine just failed on rear discs and a coil spring. Parts for 56 sheets and saved a bundle on labour!

I encountered the following which may help out others:

Disc locking screw seized on one side - Drilled out the head of the screw and jobs a good un (I'll replace it when I get round to it).

The first caliper rewind, took ages and the tool slipped several times as I was holding with the left hand and turning with the right. On the other side, I re-fitted the caliper minus the disc and pads allowing me to use the rewind tool with the caliper held securely in its housing; two hands on the turning end was a lot easier and saved a bundle of time.

The coil spring was just a case of jacking both sides up, removing the shock bolts and carefully lowering the rear wishbone using a jack on each side until the old spring could be pulled out.

Just got to see if it passes the re-test now

[huwants2no]

nice guide

[Guest]

Nice clear guide. Well done.

[cmaj76]

A couple of more helpful tips:

 

1. I would not recommend compressing the piston with a g-clamp on a handbrake caliper due to the washers, circlips, bearings and screw mechanisms within the piston and caliper housing (these can be easily damaged).
2. When winding the piston in to the caliper, wind the piston all the way in and continue another turn and then wind back by half a turn, this sets the self adjust mechanism in the caliper and ensures that the caliper self adjusts with pad / disc wear. Also if not set properly, you may find that when you actuate the piston hydraulically or mechanically, the piston will move out but then fully retract back in to the caliper.
3. When the caliper is removed, check the condition of the slide pins, make sure they are clean, straight and undamaged and replace if required. Apply brake grease on the slide pins before you reattach the caliper and make sure the caliper can slide freely.
4. Calipers which do not slide freely can cause pads to not fully retract from the disc, this micro drag is a major cause of disc warpage and judder and in extreme cases, this causes the pad material to breakdown and bond to the disc surface, resulting in reduced braking force.

I see these issues on a daily basis in my job.