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Rear brake caliper refurb

Spring has sprung and so has some more refurb work on TheHoff. I'd noticed on a few jaunts after the MOT in April that the left rear wheel was rather hot after a drive, even around town so I figured it was time to sort the rear brakes and give them some of the treatment the fronts had got a couple of winters ago... After 30 years the original ATE callipers were looking a little mangy and in desperate need of attention so I whipped them off and relocated them to the work bench...

 
...where a few knocks with a hammer separated the caliper into three parts:

  

I also noticed that each of the piston seals were hole - which made me wonder how they'd been able to actually work properly! 

  
With the seals removed I discovered much manginess lurking beneath... 

   

I can assure you that you do not want your piston looking like this! 

  
First step was to clean them up and remove all the loose rust etc - I used a drill and wire brush attachment to get them smoothed out then primed the callipers with anti rust primer. 

  
I had some Halfords brake calliper paint on the shelf so I gave it a go and duly vomited...the stuff is totally crap. Thankfully I only did one before I realised the error of my ways and stripped it all back with Nitormors and started again.

   

Doing what I should have done the first time, I went down to my local professional paint supplier and order up some 2pack high temp paint in the same RAL code as the fronts, rigged up a makeshift spray booth under my car port and set to work giving both callipers a good few layers of the stuff.
   
Once they'd dried for a day or so and had a good clear high temp lacquer applied I lightly sanded the pistons with a high grit wet n dry then inserted them complete with some new seals.

   

Then it was time to reassemble the callipers - at first I found them a little sticky, so I filed off the paint along the contact edges of the sliders and they moved freely - pretty stoked that I knew they'd be working optimally out back.

    

With both rear callipers refurbished and moving freely back they went on to the car...

   

I love the fact that Porsche still supply small items like the brake fittings and spring plates new for a reasonable cost:

   

Braking is vastly improved. Happy Days :)

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