Rear brake bleeding

The service manual I have stops at 1-15, unfortunately the brake bleeding procedure is on 1-25. Is there a trick to bleeding the rear line? I have a vacuum pump and get a steady flow of fluid out of the bleeder nipple with no air bubbles, but there is barely any resistance in the pedal. On the front line you can just get most of the air out, close the nipple and keep squeezing the lever - the bubbles will work their way to the top and just come out in the master cylinder. Does this work for the rear if I remove the caliper and let it hang below the master cylinder?

thanks

Try bleeding the line to the master. Crack the line loose from the master with the pressure on the pedal. Repeat until its squirting solid fluid. Sometimes there is a bubble inside the master piston that needs some assistance.

Turns out it was the caliper. If you ever have the thing fully empty, you have to get the system mostly bled, then remove the rear wheel and turn the caliper upside down for the final bleed. Big trapped air bubble came out, now the pedal is a rock.

Went to install new pads today (there's more to the story but this should be enough). Pushed the piston in to install the new pads. Now I have absolutely no pressure. Opened it up after to see if bleeding helps but it didn't. The question is....what happened to lose pressure and more importantly how do I fix it?!?

*I'll try taking the wheel off tomorrow and turning the caliper upside down but.....why did it do it?

If you cannot make the piston move at all then it it's the master not the caliper
I always just push the piston ALL the way into the caliper before you do anything as it makes bleeding much easier
There's really no reason to ever get air in the system while changing fluid, you just cycle fuid though til it comes out clean
Even after you have it al bled and working it's good practice to do this but sometimes you overflow the master and then when you pump it up you need to add some fluid

Pretty sure there was just a big air bubble in there. How I don't know.

Ended up pumping the brake about 20times(maybe this was enough to help with the bubble instead of taking the caliper off...worked for me) to try and build pressure then releasing bleed nipple then tighten. Did this 4 or 5 times. On the 4th try it actually started to build pressure. Now seems good.

*edit...could someone call up Yamaha and tell them the manual is screwy? Kept referring me to page 1-25 when actually "How to bleed the brake system" is on 3-25. (was looking for what fluid level should be...never really said)