Hi guys.

Quick question about bench bleeding. I know the correct process, but im just curious.....is there any good reason I cant bleed the master cylinder installed in the vehicle? Its all manual brakes(drum brakes as well), and Im just curious as to why it cant be done this way if I have a helper slowly depressing the brake pedal, and then not releasing until I tell him to do so after I see all the bubbles rise?

Ive got no problem doing it the correct way....but I suppose you could say that curiosity got the cat! FYI, with the front tires deflated, the nose down angle of the vehicle actually sets the cylinder totally level.

Thanks for any insight!

Hi guys.

Quick question about bench bleeding. I know the correct process, but im just curious.....is there any good reason I cant bleed the master cylinder installed in the vehicle? Its all manual brakes(drum brakes as well), and Im just curious as to why it cant be done this way if I have a helper slowly depressing the brake pedal, and then not releasing until I tell him to do so after I see all the bubbles rise?

Ive got no problem doing it the correct way....but I suppose you could say that curiosity got the cat! FYI, with the front tires deflated, the nose down angle of the vehicle actually sets the cylinder totally level.

Thanks for any insight!


Bench bleeding allows you to push the cylinder in further then with it on the car removing all the air that is inside the master. Without bench bleeding there could still be air in system.

Here's a great way to do it. I tried it and it works. Here a link.

http://www.cardone.com/English/Club/Service_Plus/10908BBF%20bench%20bleeder%20flyer.pdf

One bennie of doing it on the bench is that you can have the master level, whereas in the car it it somewhat nose up. May help get air out of the bore.