Received a new AC Delco single chamber master cylinder today. In the box was a red warning sticker that said “Warning Do Not Bench Bleed this master cylinder. If bench bled you will damage the cylinder.” I have never encountered this before. Could someone more knowledgeable than me explain? Thanks
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
It would have been nice for instructions but those that came with it are for a dual M/C and say to bench bleed those. Confusing.
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
Installed and bled on the vehicle. Just takes a bit longer. I have a Mighty Vac that I will use tomorrow to really flush the lines out. Hopefully it’s cooler in the morning.
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
The most recent "bench bleed" method does not use the fittings and tubes to recirculate the fluid- - - -just use plastic plugs to stop off the outlet(s), clamp the MC in a vise, and gently move the piston about 1/4" or so repeatedly until the bubbles stop coming up into the reservoir. I can't imagine how a master cylinder could be damaged by doing that. It's just purging the air that's trapped ahead of the piston without actually circulating any fluid. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
If you over travel the piston inside you run the sensitive rubber seal into the threads and damage it Then brake fluid leaks out the front of the device just enough to [censored] you off
The original master cylinder doesn’t need bench bleeding There are two holes between the top reservoir so that airlock is not possible The smaller of the two holes is often plugged after 70 years I’ve installed a couple of the original master cylinders and never had a problem bleeding it installed on truck -s
