If you have ever removed a brake booster on a 1972 (or related C3) 4-speed... - NCRS Discussion Boards

If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Larry M.
    Expired
    • December 1, 1986
    • 541

    If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

    ...please let me know how you did it.

    Underdash access to the nut on the upper, outboard booster stud is the problem. I can see the other three nuts, and can connect a socket to them with a long extension and swivel joint, but that particular one is hidden behind the neutral safety switch and it's linkage. I'll remove the driver's seat so I can squeeze in, and I can easily remove the steering column if need be.

    I've seen posts about removing the upper and/or lower dash pads but I'm reluctant to attempt to move either of them; the upper for concerns about it being brittle and breaking on removal, and the lower because I remember it being a difficult R&R due to the speedo and tach connections as well as the gauge lights. I even had to laugh at one post where when the booster was reinstalled, that one offending nut was omitted.

    Thanks for any tips.

    Larry
  • Lawrence M.
    Very Frequent User
    • February 1, 1995
    • 404

    #2
    Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

    Larry,
    It's been 18-20 years since I changed the leaking booster on my '69. Did not have to remove the column or any dash pieces. Removing the seat and laying on your back helps a lot. If you don't wear glasses use a pair of safety glasses in case a socket or tool falls on your face. That one nut is done mostly by feel. I remember one of the nuts only being turned maybe a 1/4 turn at a time. It is a bonus if you have a helper to get you a another tool you decide you need instead of trying to get out from under there once you are "in place". It can be done, but it is no fun. Good luck on the project.
    Larry
    2002 Z51 Convertible
    1969 L46 Convertible

    Comment

    • Ed H.
      Very Frequent User
      • November 19, 2015
      • 192

      #3
      Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

      UGH!!! and again, UGH!!!

      DAMHIKT, but check the clevis pin that attaches the rod to the brake pedal to ensure it is long enough that the clip can be refit...

      Some electrical tape wrapped around the 'u' joint you will most likely be needing will stiffen it up considerably, and make it much easier to get the socket onto the nuts.

      Have some of your favorite pain pills handy.

      I feel your pain.

      Comment

      • Larry M.
        Expired
        • December 1, 1986
        • 541

        #4
        Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

        Larry and Ed,

        Thanks; were either of your cars 4-speeds? Did the neutral safety switch remain in place, or did it need to come out?

        I'm definitely not looking forward to this job, and both your comments back up my trepidation.

        Larry

        Comment

        • Lawrence M.
          Very Frequent User
          • February 1, 1995
          • 404

          #5
          Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

          My car is a 4 speed. I do not remember removing the neutral safety switch.
          Larry
          2002 Z51 Convertible
          1969 L46 Convertible

          Comment

          • Larry M.
            Expired
            • December 1, 1986
            • 541

            #6
            Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

            Thanks, Larry!

            Comment

            • Ed H.
              Very Frequent User
              • November 19, 2015
              • 192

              #7
              Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

              Likewise.

              I also call to your attention that McMaster Carr is a source of a device you hopefully won't need, but... It is a hinged 'die' that can be clamped around the 'good' threads and 'unscrewed', thereby restoring the first few threads that got damaged by a cross-threaded nut. DAMHIKT either! And, seriously, check the clevis pin. If it is too 'short', squeeze the end of the booster rod such that the clevis pin is proud enough that the clip will secure it.

              Comment

              • Harmon C.
                Extremely Frequent Poster
                • August 31, 1994
                • 3228

                #8
                Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

                I had the dash,steering column and pedals out and still could not put that nut on with a socket.
                Lyle

                Comment

                • Larry M.
                  Expired
                  • December 1, 1986
                  • 541

                  #9
                  Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

                  Lyle,

                  Thanks. Am I reading you correctly - you were able to get the nut off, but not back on?

                  Comment

                  • Larry M.
                    Expired
                    • December 1, 1986
                    • 541

                    #10
                    Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

                    Ed,

                    Thank you for that clevis pin tip. I'll be installing a new booster, so repairing damaged threads shouldn't be an issue.

                    Larry

                    Comment

                    • Patrick H.
                      Beyond Control Poster
                      • December 1, 1989
                      • 11643

                      #11
                      Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

                      I've done it with everything in place including the seat, but I can tell you it is THE worst job on these cars.
                      The nuts are locking (deformed thread) type, and you will get about 1/32 of a rotation with your ratchet each time you try it.
                      Usually we're laying on our back and looking up, sometimes with a headlamp on.
                      You will need quality U-joint connectors to make this work.
                      Vice-Chairman (West), Michigan Chapter NCRS
                      71 "deer modified" coupe
                      72 5-Star Bowtie / Duntov coupe. https://www.flickr.com/photos/124695...57649252735124
                      2008 coupe
                      Available stickers: Engine suffix code, exhaust tips & mufflers, shocks, AIR diverter valve broadcast code.

                      Comment

                      • Larry M.
                        Expired
                        • December 1, 1986
                        • 541

                        #12
                        Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

                        Patrick,

                        Thanks for the encouraging news that it can be done with dash, etc, in place. Doing the math, if the stud thread count is 18 per inch, and 3/4" of threads need to be spanned, that's about 13 threads; times 32 to span a full thread, that's 416 ratchet movements to get a nut off; times 4 for all nuts equals 1664 motions. That sounds depressing and painful and like a gateway to carpal tunnel. It's a bit less depressing if a 1/4 turn of the ratchet can be accomplished each time.

                        My plan is for me to be on my back under the dash, using one hand (not sure which one yet) to stabilize the socket and u-joint swivel onto the nut, and the other hand stabilizing a very long extension rod while my wife operates the air ratchet attached to it.

                        Sounds good in theory, but it still all depends on being able to get the socket onto the nuts. Obviously since all of you who have replied have been able to do it, I'm encouraged to stick it out through the pain. Not looking forward to it, but encouraged.

                        Larry

                        Comment

                        • Patrick H.
                          Beyond Control Poster
                          • December 1, 1989
                          • 11643

                          #13
                          Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

                          You won't be able to use an air ratchet. The u-joints will be at too severe of an angle, and it will bind. Trust me.
                          And, there is no way you will get 1/4 turn at a time, for the same reason. Thus the need for a couple of high quality u-joint connectors.

                          Attached is a photo of my son doing this job.
                          Attached Files
                          Vice-Chairman (West), Michigan Chapter NCRS
                          71 "deer modified" coupe
                          72 5-Star Bowtie / Duntov coupe. https://www.flickr.com/photos/124695...57649252735124
                          2008 coupe
                          Available stickers: Engine suffix code, exhaust tips & mufflers, shocks, AIR diverter valve broadcast code.

                          Comment

                          • Larry M.
                            Expired
                            • December 1, 1986
                            • 541

                            #14
                            Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

                            Well.

                            Rats.

                            Comment

                            • Terry M.
                              Beyond Control Poster
                              • September 30, 1980
                              • 15599

                              #15
                              Re: If you have ever removed a brake booster on a 1972 (or related C3) 4-speed...

                              I see. Get the young ones to do it.
                              Terry

                              Comment

                              Working...
                              Searching...Please wait.
                              An unexpected error was returned: 'Your submission could not be processed because you have logged in since the previous page was loaded.

                              Please push the back button and reload the previous window.'
                              An unexpected error was returned: 'Your submission could not be processed because the token has expired.

                              Please push the back button and reload the previous window.'
                              An internal error has occurred and the module cannot be displayed.
                              There are no results that meet this criteria.
                              Search Result for "|||"