brake bleeding problems

im having trouble with my breaks, my pedal is really soft and goes to the floor unless pumped a couple times before I try to stop. I have traced the lines from front to back and I am not loosing any fluid. I can bleed my rear brakes and it holds pressure good for a few days then back to the soft pedal. anyone had any problems like this?

I had the same thing going on in my ride, what fixed it was a complete flush of the old fluid.

I've replaced the master cylinder on my B2200 at least once. And I had to rebuild a leaky caliper once. That's in 19.5 years.

As Emjay said, bleed all your fluid

ill give those tricks a try. I have looked the master cylinder over and don't see any leaks at all and ive never added any fluid except to bleed the rear brakes. the calipers have always looked dry with no visible leaks I can find. im going to try the fluid change first.

+1

Just a tip on the rear adjustment.I remove my drums to adjust not thru the backing plate holes.Anyhow count how many threads are showing on the adjustment rod and do the same for both sides.So if 6 threads are showing left/right need to be the same.You want the drum to slide over the shoes,not grab or really hard to install.Unless your system has other issues like front caliper slide pins stuck,sticking,rusted and our trucks have one bolt,and the other a pin made onto the holding bracket itself.I do not want to overload you with too many things,just some tips from experience.Ok

I adjust my rear brakes once per year, through the backplate hole.

im going to check it out this weekend and adjust the rear shoes and see how that helps.

adjusted the rear shoes and I now have good e-brake but the pedal still feels the same. I didn't bleed out all the fluid because the last time I bled the system (maybe 3 weeks ago) I used close to a quart of fluid, so I would think the fluid would be fresh in the entire system. could it possibly be the master cylinder?