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View Full Version : How to replace/service your front brakes.



Wobbly Dave
Wednesday 28th December 2005, 03:57
This article includes details about how to do a 280mm to 302mm conversion and in so doing explains how to dismantle and replace your front disks and pads.
The car used in this process was a 1996 850R estate. This process is the same for all 850s and 70 series (except V70 phase 2)

**Please read my brief guide on jacking safety - http://www.volvot5.co.uk/forums/showthread.php?t=1335

This process assumes you have access to the following tools...
Pair of Pliers
small screwdriver
19mm socket
15mm socket
10mm long socket/spanner
7mm Hex
Water Pliers
Torque wrench
1/2 socket driver
hand file
copper slip
brake cleaner
Jack
Axel Stand

Apply Handbrake, loosen wheel bolts (19mm), jack car**, remove road wheel.

Remove caliper spring with pliers.
http://www.bigredvolvos.co.uk/images/brake_conversion/1remove_spring.jpg

TOP TIP - Rotate steering so that it is at full lock (direction will depend on which side is to be accessed), so that the caliper is furthest out. This will make it much easier to access the rear of the caliper assembly.

Remove top and bottom guide pin covers
http://www.bigredvolvos.co.uk/images/brake_conversion/2guide_bolt_plugs.jpg
and undo guide pins till they are out of the carrier.
Optionally - Make a gap between the end of the pins and the caliper carriers - as this aids next step

Wiggle caliper free from carrier/disk.
http://www.bigredvolvos.co.uk/images/brake_conversion/3remove_Caliper.jpg

Outer pad is loose and should come away. The inner one has a retaining spring and should be pulled out of the hollow caliper piston.
Skip to +++shamfer section below if you are only replacing the pads.

You may also wish to check the integrity of the rubber caliper piston seals - make sure that there are no signs of leaks

Rest the caliper on the wishbone. Try not to twist or stress the flexible brake hose.

http://www.bigredvolvos.co.uk/images/brake_conversion/4carrier_bolts.jpg
Undo the two 15mm caliper carrier bolts - best use long bar or torque wrench - they are on tight!!

You can now remove the retaining bolt for the disk (10mm)
http://www.bigredvolvos.co.uk/images/brake_conversion/6retaining_pin.jpg

You make need to tap the edge of the old disk with a malet/hammer to free it.

Apply copper slip to hub to prevent future binding.

Clean new disks with a clean cloth and brake cleaner on both sides. Try not to get yer greasy mits on it.

Replace retaining bolt and tighten it
http://www.bigredvolvos.co.uk/images/brake_conversion/8replace_retaining_pin.jpg

Fit carrier (hand thread bolts intially) and tighten to 100ft/lbs.
http://www.bigredvolvos.co.uk/images/brake_conversion/9insert_carrier.jpg

+++Take each pad and shamfer the edges with file.
http://www.bigredvolvos.co.uk/images/brake_conversion/10shampfer.jpg

Squeeze home the caliper piston to make extra room for the new pads.
http://www.bigredvolvos.co.uk/images/brake_conversion/11squeeze.jpg
I used water pliers - but you can use a g-clamp and a thin piece of wood.

Apply copper slip to be back of the pads - being careful not to get any on the disk or pad friction surface. In the photo you can see the retaining spring on the inner pad. http://www.bigredvolvos.co.uk/images/brake_conversion/12inboard_pad.jpg
Sorry but the photo is slightly out of focus.

Stick the inner pad back into the caliper piston and push it home, so that the spring slides down the inside of the piston.

Locate the outer pad on the carrier. http://www.bigredvolvos.co.uk/images/brake_conversion/13outboard_pad.jpg

Remount the caliper by sliding the caliper/inner pad over the disk and outer pad. Secure the guide pins and tighten the to 30lb/fts. Refit plastic pin covers.

Refit the caliper spring (strong thumbs required)
http://www.bigredvolvos.co.uk/images/brake_conversion/14completed.jpg

Straighten steering up. Refit road wheel (dont forget to lower car before finally tightening wheel bolts)

I know this may sound obvious but please endeavour at all times to prevent any grease/contaminents getting on the disks - and if you do then use brake cleaner to remove it. If you by accident put your pads face down in oil for what ever reason - dont expect any braking at all???!!! - I would bin 'em and start over! LOL

For comparison I have put the 2 carriers together
http://www.bigredvolvos.co.uk/images/brake_conversion/5carrier_comparison.jpg
and the disks
http://www.bigredvolvos.co.uk/images/brake_conversion/7disk_comparison.jpg

Rainman
Wednesday 28th December 2005, 17:22
Sorry about the out of focus camera work, It was boxing day!!! Maybe the focus would improve after some altake of incohol.

Many thanks to Dave who not only supplied me with the discs and carriers, but then offered (insisted) that he came across and fit them on boxing day. All I could offer in return was some money, coffee, a dry workshop and some shoddy camera work! He also noted a few other minor things that will need attending to in the new year.

The brakes are working fine, athough still bedding in. The improvement over the original set up was worth it.

Once again Thanks Dave and have a good new year.

Richard

Shouldn't those torque measurements be in N/Meters???

Wobbly Dave
Thursday 29th December 2005, 01:20
Could you please double check the torque settings. - I dont have a Haynes on the 850 anymore.

Was a pleasure to help.

Wobbly Dave
Thursday 15th June 2006, 23:47
One thing I forgot to mention is that your gonna need longer flexible brake lines (already fitted to the car above) and if anyone doing this can take some photos and do an extension to this brake related how-to, it would be much appreciated.