which of the 4 are sticking, it could just one or all, can't realy say till you find out, it could be the proportioning valve, sticky pistons, did you replace all the brake hoses, air in the line,  the booster, when you did the job did you put a dab of antiseize on all the moving parts, is the parking brakes adjusted correctley,pull the wheels off and get dirty.  oh yea, did you flush the brake sys before you did the job so as to remove the dirty brake fluid out before you installed your new parts?anips2011-08-08 08:24:23

Just got home and had the symptom, poured refrigerated Ice water on it and it started to roll freely.  Not sure what to do to keep the master cylinder cool, any thoughts? 

as far as brake fluid dot 4 works for me,  maybe you are over filling the master cyl., take some out, 1/4" from the top is ok.

Definitely NOT normal. Usually, this is a sign of either the hoses having internal damage, or the master cyl. is not venting(releasing) properly. You have changed the hoses to braided steel lines, from what I understand, and have replaced the master 3 times.
When did this problem start? Before or after all of the changes? OR...have you been replacing these parts to try to correct the problem?
I also think if the master is too full, it might contribute to this....


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Joel Adams
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Moving the Master out from the booster can possibly create a vacuum leak, so watch out for that. There is a seal between the two, to keep booster vacuum from sucking fluid out if the master, and to just basically seal the booster pushrod.
Sounds like you may need to shorten the pushrod, anyway, if spacing the master out has corrected the problem. The pushrod length is adjustable....


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Joel Adams
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I had this exact problem with one of my cars. I had been adjusting the push rod after replacing the master cylinder to try and fine a "sweet spot" for the brake pedal. With the rod too long, the brakes began to seize heat up and seize with the rod too long. I think Adam hit the nail on the head, slightly shorten the push rod between the master cylinder and brake booster. It won't take much.....and LOSE the shims.

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<DIV style="BORDER-RIGHT: 1px dotted; BORDER-TOP: 1px dotted; BORDER-LEFT: 1px dotted; WIDTH: 90%; BORDER-BOTTOM: 1px dotted; BACKGROUND-COLOR: #eeeeee; align: center|/IMG||B|Adams' Apple said:|/B| Definitely NOT normal. Usually, this is a sign of either the hoses having internal damage, or the master cyl. is not venting(releasing) properly. You have changed the hoses to braided steel lines, from what I understand, and have replaced the master 3 times. When did this problem start? Before or after all of the changes? OR...have you been replacing these parts to try to correct the problem? I also think if the master is too full, it might contribute to this.... makes sense, the porp. valve allows the rears to come on ahead of the fronts, with the rod too long its not letting the brakes to completely release, adjust the rod with some free play like you might do a clutch maybe a 1/8" or so.

|UPDATED|8/22/2011 9:40:08 AM (AZT)|/UPDATED|

the edit thing still needs some tuning as evident on my above post, I will post it again..................makes sense, the prop. valve allows the rears to come on before the fronts, with the rod too long its not allowing the brakes to release completeley, adjust some freeplay into the rod as you might with a clutch, but maybe a 1/8" or so.

I've replaced the masters on quite a few Sharks over the years, and I have seen some that the piston in the master, where the pushrod fits, is NOT the same depth, or shape, as the one I took off. Sometimes it simply requires a change of the length of the pushrod(adjustment)....sometimes ya just have to get the correct master. I would definitely be leaning towards a small adjustment in this case, IF the dragging when hot is the ONLY issue with the brakes.

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Joel Adams
C3VR Lifetime Member #56    
My Link


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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"