You should not ever have to "pump up" the pedal when applying the brakes. When pedal bleeding, three slow strokes of the pedal, open the bleeder while the pedal is depressed, maintain pressure on the pedal, close the bleeder, release the pedal. Repeat as necessary.

Was the master cylinder you purchased a correct drum/drum power master cylinder? Like the first photo on this page? http://thefirstgensite.com/forum/kb.php?mode=article&k=1 The drum brake master cylinder should have two residual valves, one on each port, to maintain proper pressure in the brake lines. A disc/drum master will not have a residual valve for the front brakes and will displace a larger volume of fluid at a lower line pressure, causing less than adequate braking, soft pedal, and possibly unseating the wheel cylinder pistons from their proper location.

If your original master was in fact bad and not actuating the front brakes, it is possible that the front shoes are far out of adjustment, which will cause the pedal to ride low. It is not the same as a spongy pedal. I am still not sure which you are experiencing...when you press the pedal does it just go softly nearly to the floor, or does it stay fairly close to normal position but have a springy, squishy feeling? First is usually out of adjustment shoes or a bad wheel cylinder or a leak in the system or a ballooning line or an internally failed master cylinder, with nothing to resist the hydraulic pressure. The second is air in the system.

If a hose had an internal collapse the pedal would still be firm, even harder than normal. If a hose is very deteriorated, it can balloon under pressure. Examine them when you resume bleeding. The hoses should not look like they are inflating while pressure is applied.