MAKING AN OLD CAR STOP & HANDLE WELL
I think two of the goals of all car builders, beyond making the car look good, are to keep it stopping and handling well. When I first started working on cars in the mid-60s, original parts were readily available, and the "soft" asbestos brake linings could still be bought at any parts store. A few years ago, after doing a complete brake restoration on a '49 Buick Roadmaster Sedanette, I took the car out for a test drive. I had to stand on the brakes to get it to stop, even though I had done everything right, or so I thought. I went through the system until I found the problem: Brake linings. I had used the new type, available through the parts stores and some distributors, which have harder surfaces for power brakes. The '49 doesn't have power brakes. To stop efficiently, it has to have the original softer type linings.
As usual, the easiest thing is NOT the best. I got on the phone and searched e-bay, and found that there are companies selling the softer linings. I found some "Grizzly" linings for our '41 Packard on the Internet. The difference in stopping with them is amazing!
Another problem that can occur is heat buildup in the brake drums, causing brake fade after the brakes have been applied several times. There is a company in California that drills 2 holes in the drum, which lets out the heat. This was developed by the Hot Rodders in the '50s. The holes must be in the right place, and the right size, or the drum will be out of balance.
With all of this in mind, we set out to restore our current project car (a 1941 Packard LeBaron) back to its original stopping capacity. The front fenders have been removed and the car is up on jack stands, so it was easy to get to all of the brake parts. Before we removed everything, we marked each piece "Left Front", "Right Front", etc. We prepared a work table so that all parts would be laid out in order, and checked for any needed repairs.
BRAKE REMOVAL: We disconnected the brake line from the wheel cylinder, removed the four bolts that hold on the backing plate through the king pin and knuckle, and removed the backing plate. Next, we removed the return springs. Using brake pliers, we took out the hold down springs and removed the shoes and adjuster adjuster screw. These spring kits are still available at most parts stores. We got ours from Buick World. Now we could pull out the wheel cylinder push rods, remove the two screws that hold on the wheel cylinders and remove the cylinder from the backing plate. (While working on brakes, we always wear a dust mask to protect our lungs.) Our brake linings in the front were well-worn, while the back ones were only slightly worn. There were two long shoes on each of the front sides, instead of the usual "short shoe to the front, long shoe to the rear". A little research showed us that over the years someone had just put on two long shoes. No problem, since they had to be relined anyway. We sent the linings out while we were rebuilding our wheel cylinders. We had a '42 Packard 160 with the same front end, so we used its linings for correct measurement, and double checked it with our Packard brake book. The old rivets were drilled out and linings removed, shoes shot-peened, then new linings riveted in. To set the brakes up for complete drum-to-shoe roundness, we arced the shoes. This was done by measuring the drums (ours were 12" standard and cut .045") The arcing machine is then set on 12.045", the shoes are placed into the machine, then it rotates back and forth, grinding the shoe a little at a time until the entire shoe surface has been cut to the same contour as the drum, for a perfect mating of the two surfaces.
All the parts were cleaned and painted at this stage. New front inner seals were bought and bearings lubricated.
REBUILDING WHEEL CYLINDERS: First, we removed the dust covers, then tapped out the pistons, rubber seals, seal protectors and spring. We always save all of the old parts and put them in a labeled plastic bag, just in case the new kits are incomplete. We cleaned the cylinders, pistons, seal protectors and bleeder screw with mineral spirits. Joe Rabelskie honed out the cylinders at his machine shop, honing them on his precision hone, but they can be done by hand. Then we bead-blasted the push rod side of the pistons and sanded the rest with fine sandpaper, cleaned the bleeder screws, then washed everything again with mineral spirits, dried everything with brake cleaner, then did a final cleaning with denatured alcohol. To reassemble, we used Dot 3 brake fluid.
With our brakes off, it was a great time to recheck the front shocks. We put them on last month and noticed a small leak on the right shock. Matthew at Five Points (see Press Release) suggested that we go ahead and put new seals in our front shocks. This is a big job, and we recommend having it done, but we wanted to rebuild every piece of the '41, so we will know it bumper-to-bumper. We pulled them from the car and decided to disassemble, clean and replace any seals or gaskets. Care must be used in removing them, because everything must go back the way it came off.
We unbolted the shock lever clamping nut and bolt, and removed the shim, marked both of the shock levers and the splined shafts to insure proper alignment. We removed the shock lever with a puller, removed the seal caps by gently tapping them using a sharp chisel and small hammer, then unscrewed the piston caps along with the sealing disks.
We tried to remove the piston caps, but we couldn't get them off, so we heated them and sprayed penetrating oil on them. The penetrating oil burned off as soon as it hit the shock Then we remembered what an old timer had told us to use: Beeswax. We heated up the cap again and pressed a small piece of beeswax against the top of the threads, and it was drawn into the threads. To our amazement, the cap came right off! We removed the relief valve caps and the valves, keeping in order the compression and rebound valves. There are minor differences in these valves, and they must go in the holes they came out of. To remove the top freeze plug, we drilled a small hole in the plug off to one side, so as not to hit the cam under it, then pulled it out with an awl. Next month, we will continue with shock assembly and putting on the brakes. See you next month. Keep 'em driving!