In the January 2024 Driving Old Cars, my article was on the '64 Corvettes self-adjusting brakes.  In that article, I covered rebuilding the drum brakes, turning the drums, new shoes, wheel cylinders, hoses and hardware where needed.  If the brake shoe hold down springs test good, I dont replace them.  Ive found that new springs dont always have the same psi as the old ones.                            I put off a test drive until Spring, knowing that I would get into it, and Winter might not have been a good time to do that!  Then in March, I took it out and found two problems:  1.) There was a clunk coming from the left rear wheel when I applied the brakes, and 2.) the left front wheel was locked up (you guessed it.  Thats the one wheel cylinder I didnt replace.)

        The front wheel cylinder was easy, but finding the clunk in the rear end was something else.  I knew it wasnt the rear end or suspension because all of that has been rebuilt.  I always photograph each project, so before we started, I pulled up the photos.  I still use a digital camera with an HDMI cord that I can plug into my 24monitor.  Its much easier to see the details of the project.  To jack up the C2s, there is a certain way to do it.  Mine has side pipes, so you have to be even more careful.  We used the factoryjacking instructions, chocked the front wheel and lifted the frame with a scissors jack about 8in front of the rear wheel, then set up a low profilejack stand right on the front side of the rear wheel opening on the frame.  Then we removed the left rear hubcap carefully using a large screwdriver, holding it with a microfiber towel.  Now, all that was left was to remove the brake drum.  The self-adjuster had tightened the shoes, so we had to back off the adjuster.  

        I had color-coded the brake return springs, green primary and yellow secondary.  I always test the old springs because new springs are the same tension primary and secondary.  The OEM springs usually had one more coil on the secondary springs, giving them a little more pull.  As I looked and checked everything for tightness, I could see a small red cone-shaped spring that was mounted on the self-adjuster mechanism.  This spring fits on a tangmade on the actuating lever that pivots with the override pivot plate and holds tension against the secondary brake shoe.  The shoe and the actuating lever pivot on the hold down spring and pin.  This was loose.  I had left out the brake shoe hold down spring and pinsguide sleeve.  This was causing my CLUNK!  I replaced  the sleeve and cone-shaped spring and everything felt right and tight. Care must be taken to position the cone spring with the wide end of the spring facing toward the brake shoes and the narrow end slipping over the tang.   I bought three of the brake spring sets, which should include brake hold down springs, an actuating lever, the cone spring and an alignment sleeve for the spring pin hold down assembly.  Two out of the three sets were missing parts, usually the cone springs.  It is better to buy your sets from reputable Corvette vendors than online. Now with everything back together, I sprayed everything off with brake cleaner, wiped it all down and put the drum back on and bled each wheel, starting with the farthest wheel from the master cylinder:  RR, LR, RF, LF, repeating three times using Dot3, topping the master cylinder after bleeding the wheels.  I took the car  for a test run.  NO CLUNKS and it stopped well.  The noise was gone.  

        It was time to fix another problem that Ive had since I bought the car:  TO LOWER THE CLUTCH AND BRAKE PEDALS.  They have always been too highabout 9from the floor.  I am 511tall and have to drive with my feet held up so I can get to a fast stop.  The brake pedal should be about 5 1/2from carpet to the top of the pedal, and the clutch 4 1/2from carpet to the top of the pedal (for me).  These pedals hang, rather than go through the floor, and have several ways to reduce travel height.  Care must be taken not to adjust the clutch where it grabs too soon from the floor or it has less than 1travel downward from rest at the top.  Both pedals have rubber bumpers that mount at the top of the pedal arms to keep them from going too high as the pedal returns.  The rubber bumper pushes up into a slot at the top of the pedal arm.  Easier said than done. Mechanic Steve Bailey used a die grinder with a pointed burr to shape the bumpers, then pushed them into place.  Then, keeping in mind that whatever adjustment is made can cause another problem, ie:  adjusting the brake master cylinder pedal rod can cause the brakes to stay engaged, making them get hot, or the brake lights to stay on.  Fortunately, Steve and I were able to insert the rubber bumpers and lower the pedals.  

SOLVING MY PROBLEM:

The clutch bumper and the brake bumpers are different.  The clutch bumper is larger.  Now the clutch pedal is 4 1/2from the floor and the brake pedal is 5 1/2from the floor.  Through all of this, the brake harness and brake lights were kicked around,  but when we checked them, they still worked fine.  There is so much plastic in the Corvettes, it is a good idea to run a ground to each component.  

        A few years ago, we did an article* on re-wiring the 64s tail lights and signal lights.

        I believe like Formula One racer Stirling Moss who said he always had his car fitted to his way of driving, so thats what Im doing with this car.  I am going to mount a 3x 3x 6solid rubber block on my left kick pad to rest my foot on while driving, so that it will be right therewhen it is time for the clutch.  I want to drive and rally with this car and will make similar modifications when necessary.  

Back to the garage!  Enjoy your cars and keep em driving!