I replaced my PowerMaster motor unit, because my old motor, was causing the 30 amp brake fuse to blow. The new motor solved that problem. I followed the GM Service Manual proceedure(Exactly)for properly installing the motor unit(I kept the reservoir full, never let the pump run dry, shut motor off before 20 seconds total run time, cycled the motor(10-15 times, with the engine off, ignition key in "Run" position)to(Which I presumed would bleed air out of the booster side?)? However, while cycling the pump, the brake pedal wants to go all the way to the floor-but, whenever I depressurize the accumulator, the brake pedal, pumps up like it should(And, doesn't go to the floor). I had also, replaced the accumulator with a new one(At the same time I replaced the new powermaster motor). After depressurizing, the pump took only 15 seconds to fully pressurize the accumulator. During pump cycling,(Key in "Run", engine off)the run time was 6 to 6.5 seconds until motor shuts off.
QUESTION: I assumed from the information in the GM service manual, that the booster section, was seperate from the main master cylinder section. Also, that the booster side, could be bled(To remove air)by cycling the motor, with ignition key in "Run"(Engine off). Is it possible, for air to leak from the booster side into the main master cylinder side-therefore requiring the main master cylinder lines to have to be bled--or? I ask this, in view of the fact, that up until my old motor failed, my brakes were fine(My 1987 TR only has 44,000 actual miles on it). Only the motor unit was changed(No other brake lines removed)and the car sat for about two months before I had completed the motor installation. I don't wish to bleed the main master cylinder lines(If it's not necessary)which is why I'm asking for opinions on all possible reasons for my newfound, brake problem(There must be a specific reason for this?)and, I will appreciate getting various input on this? Thanks!
QUESTION: I assumed from the information in the GM service manual, that the booster section, was seperate from the main master cylinder section. Also, that the booster side, could be bled(To remove air)by cycling the motor, with ignition key in "Run"(Engine off). Is it possible, for air to leak from the booster side into the main master cylinder side-therefore requiring the main master cylinder lines to have to be bled--or? I ask this, in view of the fact, that up until my old motor failed, my brakes were fine(My 1987 TR only has 44,000 actual miles on it). Only the motor unit was changed(No other brake lines removed)and the car sat for about two months before I had completed the motor installation. I don't wish to bleed the main master cylinder lines(If it's not necessary)which is why I'm asking for opinions on all possible reasons for my newfound, brake problem(There must be a specific reason for this?)and, I will appreciate getting various input on this? Thanks!
