No brakes after master cylinder swap
#1
CF Veteran
Thread Starter
No brakes after master cylinder swap
G'day from Oz, it's been a while, but need your help again. Done searching and all, but other than " it's needs more bleeding" didnt come up.
Trying to get my finger around squishy brakes (but relatively ok braking power) I had for a long time, replaced pads and bled after that (no change) and today replaced my master cylinder.
Cardone MC, bench bled it, kept it topped up during installation and bleeding. Brake pedal didnt feel too bad when had key off at first, but when started, brake virtually gone, almost no resistance. Cant 'pump' it up either.
Re-bled thoroughly (one-man-technique this time)...still almost no resistance and no brakes.
Gone through 1.5 ltr brakefluid, not a bubble in the lines, not the tiniest.
No leakage to be seen
MC was pre-assembled unit
Rear drums have been adjusted, right wheelcylinder replaced 20K ago
With old MC in place no real issues other than the squishy brake, no leaks
When bench bleeding MC, it did not appear to be faulty, good stroke power
Not adjusted the 'rod' because unit appeared to be exact same size as old MC
However: Now no brakes, no ride, no idea.
Appreciate your input,
Cheers.
Trying to get my finger around squishy brakes (but relatively ok braking power) I had for a long time, replaced pads and bled after that (no change) and today replaced my master cylinder.
Cardone MC, bench bled it, kept it topped up during installation and bleeding. Brake pedal didnt feel too bad when had key off at first, but when started, brake virtually gone, almost no resistance. Cant 'pump' it up either.
Re-bled thoroughly (one-man-technique this time)...still almost no resistance and no brakes.
Gone through 1.5 ltr brakefluid, not a bubble in the lines, not the tiniest.
No leakage to be seen
MC was pre-assembled unit
Rear drums have been adjusted, right wheelcylinder replaced 20K ago
With old MC in place no real issues other than the squishy brake, no leaks
When bench bleeding MC, it did not appear to be faulty, good stroke power
Not adjusted the 'rod' because unit appeared to be exact same size as old MC
However: Now no brakes, no ride, no idea.
Appreciate your input,
Cheers.
#2
CF Veteran
pull both master and booster. remove master to see if fluid is leaking into the booster.
you may need to adjust the pedal rod out so it comes into contact with the master. too much and your brakes will drag. too little and you will feel the pedal have too much dead spot.
it may take a few times pulling the master to adjust, but you will eventually get it right.
you may need to adjust the pedal rod out so it comes into contact with the master. too much and your brakes will drag. too little and you will feel the pedal have too much dead spot.
it may take a few times pulling the master to adjust, but you will eventually get it right.
#3
CF Veteran
Thread Starter
pull both master and booster. remove master to see if fluid is leaking into the booster.
you may need to adjust the pedal rod out so it comes into contact with the master. too much and your brakes will drag. too little and you will feel the pedal have too much dead spot.
it may take a few times pulling the master to adjust, but you will eventually get it right.
you may need to adjust the pedal rod out so it comes into contact with the master. too much and your brakes will drag. too little and you will feel the pedal have too much dead spot.
it may take a few times pulling the master to adjust, but you will eventually get it right.
If the rod would be to far out now, wouldnt I feel the dead spot and than resistance? Its kinda more very low resistance all the way through now..
Last edited by Roler; 11-01-2013 at 10:02 AM.
#7
CF Veteran
Thread Starter
No, not this time. Pulled the right calliper several days ago, but that was with the old MC on there. No brake issues after that.
its not the A1 Cardone, but the Cardone. Read somewhere that the A1 Cardone not the best choice is.
The cardone isnt exactly an EL Cheapo, compared to Centrix, Wagner and A1 Cardone. Same price as a Bendix, but couldnt get that one via Amazon.
its not the A1 Cardone, but the Cardone. Read somewhere that the A1 Cardone not the best choice is.
The cardone isnt exactly an EL Cheapo, compared to Centrix, Wagner and A1 Cardone. Same price as a Bendix, but couldnt get that one via Amazon.
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#8
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You can measure quite easily to see if the rod from the booster is long enough or needs adjusting.
#9
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#10
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#11
CF Veteran
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held it next to each other (so it might have been a millimeter difference if anything)
the depth inside the piston rod I did not measure. I would think that a mm difference would not likely cause such a dramatic loss of resistance ALL the way through? On application of the brake yes, but not all the way through..(not that I question the fact the measuring will give the answer
the depth inside the piston rod I did not measure. I would think that a mm difference would not likely cause such a dramatic loss of resistance ALL the way through? On application of the brake yes, but not all the way through..(not that I question the fact the measuring will give the answer
#12
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held it next to each other (so it might have been a millimeter difference if anything)
the depth inside the piston rod I did not measure. I would think that a mm difference would not likely cause such a dramatic loss of resistance ALL the way through? On application of the brake yes, but not all the way through..(not that I question the fact the measuring will give the answer
the depth inside the piston rod I did not measure. I would think that a mm difference would not likely cause such a dramatic loss of resistance ALL the way through? On application of the brake yes, but not all the way through..(not that I question the fact the measuring will give the answer
#13
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Thread Starter
Guess you're likely right about that....well, first I will try if bleeding the prop valve will improve things before looking into adjusting the rod. Does the FSM have something on this (not near mine at the moment)?
#14
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I've never seen it covered. Been doing it for years. Saw it in an old repair manual recently. Worth checking.........You'll figure out how to measure it. Toothpick? Piece of wire? It will be blatantly obvious when you look at it.
#15
CF Veteran
Thread Starter
Think the measuring will be do-able....is adjusting the rod in the booster too? It will probably be a trial and error...
Last edited by Roler; 11-02-2013 at 07:03 PM.