1971 ls5 coupe power brakes
11-17-2017, 07:29 PM
#21
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No. Absolutely not. Changing to a new MC is when your foot goes to the floor or no longer holds pressure. You have none of that. You have good brakes. I believe with time you will adapt to their sensitivity. If it were mine I would pull the MC forward as far as the lines would allow. Try to get a piece of clay on the end of the rod, tighten nuts, remove MC and see how much gap you have. I suspect the rod is the culprit. Is your brake pedal high off the floor?
11-17-2017, 07:33 PM
#22
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Ok, you have some history info. But still unknown is, if its the correct setup. Some MC only fit 3-4 yrs. then changed again. The power brake MC is different than manual. Its easy for a novice to order & install the wrong unit. This goes back to post #11.
Supposedly the rod has to have a air gap between the tip and the MC piston. Don't remember how much, maybe 0.100". I recall someone stating to put some clay / Silly-Putty on the rod tip. Snug down the two MC nuts, apply brake, remove MC, inspect thickness of clay (or lack off). Without a gap, it is possible to have your brake pads dragging ALL the time. Not good. But too much of a rod gap allows the pads to be retracted. Not good either.
And as far as a adjustable booster rod? I believe that is accomplished at the clevis under the dash. But I think some yrs are non-adj.
Supposedly the rod has to have a air gap between the tip and the MC piston. Don't remember how much, maybe 0.100". I recall someone stating to put some clay / Silly-Putty on the rod tip. Snug down the two MC nuts, apply brake, remove MC, inspect thickness of clay (or lack off). Without a gap, it is possible to have your brake pads dragging ALL the time. Not good. But too much of a rod gap allows the pads to be retracted. Not good either.
And as far as a adjustable booster rod? I believe that is accomplished at the clevis under the dash. But I think some yrs are non-adj.
11-17-2017, 07:37 PM
#23
Pro
Thread Starter
No. Absolutely not. Changing to a new MC is when your foot goes to the floor or no longer holds pressure. You have none of that. You have good brakes. I believe with time you will adapt to their sensitivity. If it were mine I would pull the MC forward as far as the lines would allow. Try to get a piece of clay on the end of the rod, tighten nuts, remove MC and see how much gap you have. I suspect the rod is the culprit. Is your brake pedal high off the floor?
11-17-2017, 07:53 PM
#24
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One other thing comes to mind. Maybe the front calipers are "grabby" because the rears brakes are doing nothing at all. That could be a Proportioning Valve issue. And maybe, just maybe the MC, but not to likely.
11-17-2017, 07:59 PM
#25
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Maybe everybody, you, I and gn mngr are overlooking the simple explanation. Somebody put some pads and rotors on there for race track use.