Is it possible to bleed a master cylinder on the vehicle?

Yes, install like normal but don't hookup the brake lines from master to car instead use the bleeder adapters in new master box and just loop line fittings back into reservoir and bench bleed on car. Once you have no more bubbles in master hook up cars lines and bleed at wheels like normal.



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Yep, done it many times like that! Nice to have those clear lines to see any bubbles.