If you install a new Master Cylinder, you'll have to bleed your brakes, there's no way around it. Bleeding a Master Cylinder can seem like it takes forever. The pros use strong vacuum pumps to suck the air bubbles out of the braking system quickly, but we don't have these at home. Without it, you have to use the pump pump pump method, a long process and sometimes unsuccesful, meaning you have to do it all over again.
There's a way to avoid a drawn out brake bleeding session -- bench bleed your Master Cylinder. Bench bleeding basically means that you are bleeding your Master Cylinder on your work bench, out of the car. How can you bleed a Master Cylinder before you install it? We'll show you how. It's actually really simple.

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Master Cylinder