for you brake bleeder folks
 

put in new metelli master cylinder
all new brake hoses
rebuilt both rear calipers, fronts are recent

bench bled the master poorly, didn't have right technique
bench bled it again after installed in the car
got only a few blobs of air in the first several rounds of plungeing the cylinder

then zero more air

still with the mushy deep diving pedal

84 300TD

anybody know what I'm doing wrong??

yes, repeatedly

then bled master in vehicle, maybe 40 to 50 strokes,

first the two front wheels only with the one line feeding rears screwed in,

then the one feeder to rears bled solo with front feeders screwed in as in running condition, got significant intermittent air into the reservoir from fronts but the feeder to the rear produced no air

feels a little better but still deep plunge before it begins to feel firm

in all cases bled the lines to the calipers after MS bleedings