I really shouldn't mention this but the Bendix factory guy taught me in a brake tech class many many years ago.....
Remove drum and peel back the rubber dust cap & insert a .002" feeler gauge in between the piston and cylinder untill it begins to dribble , have a helper pump the brake pedal and stop when bubbles stop coming out - one must be very carefull with a rag to prevent any brake fluid from reaching the lining or the game's over .
Note : this can kill old brake cups that only have a tenuous seal in the first place , any signs of leakage when the dust cap is peeled back means no go , you must rebuild / replace the offending cylinder .
This method also works quite well on vertical slave cylinders like those used in older C- series
trucks from that other brand - you know the bad one ('F') .
When bleeding brakes , _always_ use _ONLY_ a 6 point box end wrench to help prevent stripping and when faced with older machinery , before anything , smack the bleeder nipple hard with a 32 Oz. ball pien hammer _before_ you try to open it , 99 % of the time this will shock it and release it .
Good luck and have fun ! .
