Do I need to bench bleed my new Master Cylinder?

[Chad300tdt]

I just replaced all the rotor and calipers and I'm getting ready to replace the master cylinder. I plan to use a Motive Power Bleeder once the master cylinder is in.

Do I need to do a bench bleed prior to installing the MC if I am pressure bleeding the system anyway?

[dkveuro]

Yes and ..er... no.

Pressure bleeding from the caliper to the m/c it could be said, no need to bleed the m/c at the bench.

In every case I always bench bleed.


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[Chad300tdt]

That's what I'm leaning toward.

Has anybody used a pressure bleeder and bled the MC in place? Would doing this cause any problems?

[dkveuro]

Here's the reason most m/c's require bench bleeding....

The pedal will not often stroke the piston in the m/c all the way to the end.

Bench bleeding has no such restriction, you can push the piston all the way down the bore and no air is likely to be trapped in the end of the bore causing spongy pedal syndrome.....supposing you have correct bleeding hoses to bench bleed.


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