paul.h Posted September 5, 2008 Posted September 5, 2008 Members felt this would be a good post to pin at the top. It contains the important points to do the job:- raise the car suspension to its highest level, jack up the car, use axle stands, remove wheel,- use brake cleaner/WD40 in the holes in the caliper to help free the bolts (only needed the first time the caliper is removed when loctite is still down the length of the caliper bolt holes),- remove the brake pad cover bolt/ cover/ brake pads (knock out from below if seized in place) but then refit the bolt which held them in place so the caliper does not split (3.5 Nm so not too tight),- clean the caliper a bit,- use a file/screwdriver to scrape any rust off the brake disc and consider removing the wear ridges but if the discs are worn too thin (less than 12 mm) they must be replaced. Then clean with emery paper (180 grit works ok) to remove any glazing. Leave wiping with brake cleaner until the caliper has been refitted in case any grease gets on the disc.- unclip the caliper brake pipe from the 2 plastic clips on the suspension arm. The pipe will release fully from the clips when the caliper is moved. The brake pipe does not need to be disconnected from the caliper.- undo the caliper bolts enough so the caliper is free (if the loctite has been removed the bolts can be removed completely),- slacken the disc holding screws (I have never had to do this),- move the caliper out and rest it on a 2.5 litre paint tin (or similar),- clean/scrape the corrosion from the back of the caliper and suspension arm using a file (and maybe a drill or emery paper). Clean the pad contact points on the caliper.- apply copper grease to the caliper/suspension arm contact faces or use a gasket made from heavy duty black plastic bag or use the Citroen recommended Loctite formajoint 510 to prevent galvanic corrosion due to contact of the different metals of the alloy caliper and steel suspension arm,- apply copper grease to the caliper where the brake pads contact (it is easier at this point and there is no risk of getting any on the brake disc),- refit the caliper but fit the bottom caliper bolt first since the top one does not line up (before knowing this I fit a top bolt first but cross threaded and snapped it), torque setting 70 Nm,- clean the brake disc with brake cleaner on a tissue/rag,- clean the old brake pads and then rub the friction surface on emery paper (180 grit works ok) on a flat surface, refit the brake pads (or new ones if too worn or not worn evenly), refit the brake pad shims. Use a bit of copper grease down the pad backing plate sides and back and on the shims to avoid seizing/squealing and in the pad retaining bolt holes on the caliper to avoid corrosion (this part of the caliper can corrode and break off). Fit the pad retaining spring and bolt (3.5 Nm) and cover.- refit the brake disc screws (10 Nm) if slackened and the wheel (90 Nm).- use the brake pedal to push out the brake pistons before driving. If new pads are used they will take a few days of normal use to bed in and until then the brakes will not work as well as normal.To remove the loctite from the caliper bolt holes a long 10mm drill could be used but this will require removal of the bolts (do one at a time and refit whilst the other is done) and be carefull not to touch and damage the threaded part in the suspension arm. Officially I think you should inject fresh loctite down the length of the bolts through the holes in the caliper when refitting, I suspect to prevent corrosion between the bolts and suspension arm and if so then copper grease would do, but as a minimum loctite should be used at the bolt end in the suspension arm so they do not become loose. Edited 11/6/2013.Additional notes to help with the bolt removal when there is still loctite down the caliper bolt holes, copied from a 19/10/2008 post and successfully using this method on a mark 1 and mark 2 C5. It was found best to remove/clean up/grease and refit the bolts on a separate day to pad removal/caliper corrosion cleaning due to the time taken: Yesterday I removed the loctite from the driver's rear caliper with the caliper still in place and learnt a bit more (previously I had just undone the bolts enough to clear the suspension arm on this caliper and the other one I had to remove completely before hammering out the bolts).One caliper bolt was removed and the loctite drilled out of its caliper hole whilst the other was kept in place as in the above procedure so the caliper did not split.Once a bolt is undone from the threads on the suspension arm it stopped moving out. After futile attempts with a hammer and also trying a bolt from the back of the suspension arm with the same thread (10mm x 1.25) to push out the bolts, I eventually successfully used a pry bar/crow bar to lever against the back of the bolt head (protected by a large washer) against the caliper (and a piece of wood as the bolt moved further out) whilst continuing to turn the bolt. Gradually the bolts moved out but it still took a lot of effort and time and it was then too late to bother removing the pads and cleaning up the back of the caliper. WD40 and brake cleaner were used in the small holes in the calipers but their benefit was not great (if any). The pry bar I have is a Draper one, L shaped with cut outs for nail removal so this helped keep it against the bolt. There is probably a puller that would make this job easy. The long 10mm drill was a masonary one since these are cheaper. The bolt hole is probably 11mm so the loctite also needed cleaning out with a file and long screwdriver so the bolt is a nice loose fit. A vacuum cleaner helps in removing the mess from the bolt holes. Edit 26/11/2014:Some other posts worth a read:http://www.citroen-owners-club.co.uk/citroen/topic/22077-rear-brakes-to-use-loctite-or-not/http://www.citroen-owners-club.co.uk/citroen/topic/22076-c5-mk1-2001-22hdi-replacing-rear-brake-calipers-and-discs/http://www.citroen-owners-club.co.uk/citroen/topic/22073-c5-mk1-2001-22hdi-advice-on-brake-bleeding/ To see other comments and ask questions about this procedure please use the thread here.Disclaimer Edit 4/9/2015:The post has been edited to better reflect the best order for the various tasks.
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