Ford Repair: 1991 ford explorer brakes, rear shoes, question thanks

Question
QUESTION: 1991 FORD EXPLORER 4.0 2WD MANUEL TRANS.
REPLACED LEAKING BRAKE FLUID LINE, REPLACED REAR SHOES.
PROBLEM.CAN BLEED FRONT BRAKES BUT BACKS WILL NOT BLEED.
LOOKING AT THE REARS I BELIEVE THE BACKS HAVE NOT BEEN WORKING AT ALL.

ANSWER: Hi Lisa,
      It's possible that you have a bad master cylinder. Try bleeding at the fitting of the master, while checking for air escaping. See if it will build pressure.  You could have air trapped at the master, which won't allow you to get fluid to the wheels. Good luck!    Shaun.

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QUESTION: Thanks for getting back so soon. Even if the fronts are bleeding and the backs are not? I can still have air trapped at the Master? Also Do you have any tips to bleeding the Master the easiest way. Thanks

Answer
Yes Lisa, it could still be bad. The cylinder has two lines: one for the front, one for the rear, so they operate somewhat separately. If the cyl. goes dry on just one channel, it will get air trapped inside. Make sure the reservoir is full, have someone hold down the brake pedal, crack one fitting at a time loose SLOWLY while wiggling the metal line while loosening .You can have both lines loose at the same time, but MAKE SURE that you don't let up on the pedal until the fittings are closed and tight again.One fitting will probably be straight fluid, the other will squirt air out followed by bursts of fluid. Bleed both channels until you get solid fluid flow from both lines, and then attempt to bleed at the wheels, starting at the pass. rear.  Shaun.