New rear PMB alloy calipers. Now no break pressure Options

[Downerman]

OK, OBVIOUSLY no negative to the calipers. Here's the deal..... removed the 911 rear calipers (well for that matter the entire swing arms) but I just let the brake fluid lines hang and drain into jars. Finally got my swing arms mods done and now putting on the new calipers. Filled the brake resevoir up and had all 4 wheels off the car. Used my handy dandy brake sucker pump and had fluid running to all four bleeders on the rear (2 each for a caliper) and then did the fronts. Had to refill a couple of times because I was pulling some darker fluid until it was clear. Went into the cab and hit the breaks. Nothing.... I mean NADA. Pumped like a 100 times to no avail.

RE-DID the entire process again. NADA and I mean nothing. So, I'm wondering if my master has gone south in this time line?? and why?? Seems the only logical answer at this point. Anyone have any ideas?

Dave

[Tbrown4x4]

If the M/C is old, sometimes rust and dirt settle to the bottom of the bore and when you bleed the brakes the cup seals can be damaged. If you bleed the brakes by pushing on the pedal, the cups are pushed past their normal range of travel and can run over this junk and tear the seals. Pressure bleeding is best, but not as simple.

The low position of the master cylinder in the 914 makes it harder to rid the system of air. Remember to always bleed the caliper farthest away from the M/C first, then continue in order to the closest caliper. Then do it again.

[Downerman]

Thanks everyone for the info. Yeah I started with Passenger rear, drivers rear, passenger front and drivers front. Bottom line though is I have brake fluid for days coming out clear and bubble free from every bleeder. Just NADA at the peddle. I have been scrambling to try and find a method of bleeding the master cylinder but nothing makes sense. If I don't have ANY pressure in the peddle will simply losening the nuts on the MC release the air? How could it if there's no pressure?

I'm losing my mind on this simple issue.

Dave

If the M/C is old, sometimes rust and dirt settle to the bottom of the bore and when you bleed the brakes the cup seals can be damaged. If you bleed the brakes by pushing on the pedal, the cups are pushed past their normal range of travel and can run over this junk and tear the seals. Pressure bleeding is best, but not as simple.

The low position of the master cylinder in the 914 makes it harder to rid the system of air. Remember to always bleed the caliper farthest away from the M/C first, then continue in order to the closest caliper. Then do it again.