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Bench Bleeding Brake Master Cylinder

rgfrey

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Happy New Year all! I should receive my new brake master cylinder (MC) tomorrow for my 1959 BN4 100-6. Can anyone give me some advice as to how to bench bleed the MC prior to installing it?
 
Actually, the way the BN4 master cylinder is constructed, it doesn't need bench bleeding. Because the fluid reservoir is integral to the MC and the brake line exits the top of the MC, any air will automatically go out the brake line.
 
Rgfrey-I installed the new MC then attached the feed piping from the reservoir . At the discharge port I connected a clear tube that returned fluid to the reservoir can .

Next I slowly pumped the brake pedal until there were no bubbles visible in the clear plastic piping. Job done.

Remove plastic pipe at discharge port and connect hard pipe.


Be sure to bleed driver rear , then passenger rear, driver front followed by passenger front brake drum.
 
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