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Brake master cylinder overhaul #1

I started the overhaul of the brake master cylinder after the clutch slave cylinder.
This days work was removal and disassembly of the brake master cylinder.
My onboro ALFA is early type (Mk. I) 1750GTV RHD.  The brake master cylinder is made by BONARDI and it is installed on the frame under the floor together with the clutch master cylinder (this is made by BENDITALIA).

Regarding the removal, there was a little try and error.
(1) Remove the pipes
Then, I tried to separate the linkage rod connecting to the brake pedal.  However, the fixing nut was so hard that I changed the process.
(2) Remove the bolts fixing the brake master cylinder on the frame.
(These bolts were also fixing the clutch master cylinder penetrating the frame.)
(3)&(4) Separate the linkage rod from the brake pedal, and remove the brake master cylinder together with the linkage rod.
(The linkage rod and the pedal were fixed by a split pin.)


Next was the disassembly of the brake master cylinder.
(5) Fix the linkage rod with vise and remove the fixing nut.  Then, separate it from the rod of the brake master cylinder.
(6) Remove the piston inside the cylinder.  At first the piston was sticking with rust and could not be removed.  However, after moving it several times, rust was gone and the piston could be taken out.
(7) The condition of the piston was not bad.
(8) There was no remarkable scratch inside the cylinder.  It was also good condition.


(9) Disassembled parts.


I heard that the quality of the reproduction parts of the BONALDI type brake master cylinder was not good.  Therefore, I thought it would be better to overhaul and use the original brake master cylinder. I was a bit relieved with knowing that the condition of the brake master cylinder was good and it could be reusable.


(My original blog was written on 8th Jun 2009)

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