johnc Posted July 18, 2005 Share Posted July 18, 2005 Bought another Z over the weekend: 1971 Series 1 with a 2.8 and a 5 speed. Besides a rear suspension issue (car turns right when the rear suspension bottoms) I've got a strange braking problem. The car has the stock MC and booster and stock front and rear brakes. The pedal moves freely (with no resistance) about 2" inches and then BAM! Lots of brake. There's almost no modulation, just a rock hard brake pedal after 2" of no resistance travel. I've never felt this in any Z (or any other car for that matter) and all the components appear stock. With no booster (drove the car and shut the motor off) the brakes feel fairly normal. I haven't taken anything a part but I suspect the booster or the pushrod is the culprit. Any other ideas? Quote Link to comment Share on other sites More sharing options...
JMortensen Posted July 18, 2005 Share Posted July 18, 2005 It's the booster. Seen that problem before. Quote Link to comment Share on other sites More sharing options...
srgunz Posted July 19, 2005 Share Posted July 19, 2005 John, pull the m/cyl, remove clip, washer and push rod from booster. Fish out reaction disc. from bottom of cannister. Glue the rubber disc to end of push rod and put back together. Should be ok then. I went thru this on mine. Yours acts exactly the same as mine did. I went thru this before there were any internet Z sites! What a bitch. Quote Link to comment Share on other sites More sharing options...
johnc Posted July 19, 2005 Author Share Posted July 19, 2005 Thanks Steve and Jon. I ended up buying a rebuilt booster for $120 as I already had a core. I'll pull the bad one off the car later this week and tear it a part and try to fix it. I've never rebuilt a booster so this will be something new. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted July 19, 2005 Share Posted July 19, 2005 FWIW my best friend had this happen on his Z one day out of the blue. He'd touch the brake and nothing, then suddenly the car would skid to a stop. Of course this happened on his way to work in traffic. You can imagine how fun that was! Not sure how the reaction disk can fall out while everything is together. I thought you had to take the master off for it to fall out. Quote Link to comment Share on other sites More sharing options...
johnc Posted July 21, 2005 Author Share Posted July 21, 2005 Fish out reaction disc. from bottom of cannister. Glue the rubber disc to end of push rod and put back together. Exactly the problem. In fact, when I put the rebuilt booster on and was adjusting the pushrod, the reaction disc fell out! So, being the lazy sort that I am, I fished the reaction disc out of the old booster and glued it to the end of the pushrod on the new booster. Now I'm carrying a spare reaction disc around in my rebuilt booster... Funny how a 1" x 1/4" rubber disc has so much affect on brake feel. Quote Link to comment Share on other sites More sharing options...
johnc Posted July 21, 2005 Author Share Posted July 21, 2005 BTW... thanks everyone for the help. Quote Link to comment Share on other sites More sharing options...
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