Brake Servo

and

Master Cylinder Change

 

Brake Pedal Securing Arrangement

My Servo had been rusted for a long time, not rusted to the point of being holed as many are, but not looking too pretty. There are some photos later to see how bad it was, but I had resolved to change it. I obtained a pristine servo from a scrap XR2i with a master cylinder and fluid reservoir for £28. But on inspection the reservoir and master cylinder had debris in them so I decided to use the servo and my new master cylinder and old reservoir to do the job. First thing to do is remove the R clip and pin from the brake pedal (see picture)
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Releasing the Servo

Next undo the four nuts in the drivers foot well. This releases the servo from the bulkhead

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Removing old Servo and Master Cylinder (MC)

Next suck out all the fluid from the reservoir and cover all paintwork to soak up spillages, then undo the three brake pipes from the master cylinder and pull out the vacuum pipe. If using a new master cylinder like I was you'll need an M12 bleed nipple to blank off the fourth connection as visible in the picture unless you can remove the original. The reservoir just pulls out of the rubber seals on the top and pushes into the new master cylinder and the master cylinder just pulls away from the servo once you've undone the two nuts on either side of the oval metal shape at the foot of the MC. I would suggest you remove these ancillaries off the car to minimise spillage and if you have undone the unions (3 off), the nuts in the foot well. (4 off) and the gudgeon pin in the brake pedal then the servo and master cylinder will just pull away from the bulkhead - it may take some wiggling and force.
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Putting the New Cylinder On

Now connect all ancillaries except the reservoir together off the car and fit to the bulkhead again. Then connect the brake pipes to the MC and tighten all nuts and unions. Once in place fit the reservoir by pushing into the rubber seals and fill the reservoir before re-fitting the gudgeon pin at the brake pedal. Next bleed the brake system well by the following method (you could use and easybleed pressure system, but I prefer the manual use of the brake pedal method as it is more controllable). Fill the reservoir and loosen the blanking bleed nipple in the MC having fitted a clear tube to the nipple, pump until clear fluid passes along the clear tube and then tighten the nipple. Next repeat the process of bleeding at each wheel until all old fluid has passed and clear new fluid with no air bubbles comes out of each nipple (this will take at least 1.5 litres of fluid), I suggest you bleed the front wheels first then do the back and then redo the front, as this ensures all air is expelled. Make sure you keep the reservoir full throughout - if not you'll have to start again!!!!

 

By the way, the pictures here are of the old cylinder taken before replacement, the new one is much shinier!!!! Forgot to take pics of new arrangement with shiny black servo and shiny silver Master Cylinder - wanted to drive it!!!!

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Putting the New Cylinder On

Now connect all ancillaries except the reservoir together off the car and fit to the bulkhead again. Then connect the brake pipes to the MC and tighten all nuts and unions. Once in place fit the reservoir by pushing into the rubber seals and fill the reservoir before re-fitting the gudgeon pin at the brake pedal. Next bleed the brake system well by the following method (you could use and easybleed pressure system, but I prefer the manual use of the brake pedal method as it is more controllable). Fill the reservoir and loosen the blanking bleed nipple in the MC having fitted a clear tube to the nipple, pump until clear fluid passes along the clear tube and then tighten the nipple. Next repeat the process of bleeding at each wheel until all old fluid has passed and clear new fluid with no air bubbles comes out of each nipple (this will take at least 1.5 litres of fluid), I suggest you bleed the front wheels first then do the back and then redo the front, as this ensures all air is expelled. Make sure you keep the reservoir full throughout - if not you'll have to start again!!!!
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The Old Servo and Master Cylinder


As you can see the condition of the old Servo and Master Cylinder was less than ideal and really needed sorting

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