Work Log:



Healey Log 3a

Rear Drum Brakes - Dismantling

With calipers off work commenced on the rear brakes

  1. 1.The drums are secured to the axle hub by five stud bolts. We soaked the bolts well prior to working them off using an open-end wrench and hammering the wrench with a dead blow hammer. Each nut was carefully removed by adding small amounts of WD40 while working the nuts loose

  2. 2.Under the axle hub are two Phillips head screws that hold the drum in place presumably to prevent it from falling off the studs when the studs are removed, but frankly they seem redundant. We did could’’t budge them so stopped at this point, but gave all screws a multiple shots of WD40 and left them.

  3. 3.At the rear of the brake is a rectangular brake adjusting bolt that we attempted to use to back off the brakes from the brake drum. Both bolts were frozen and could not be moved. WD40 was applied to each.

  4. 4.The WD40 soak combined with hammering each screw on the head using a large Philips head screw driver and large ball peen hammer did the trick on the two retaining screws. However, both drums are frozen to the brake shoes and could not be budged. The brake adjusting screw is still not moving. WD40 was sprayed inside each brake assembly through the front screw holes. The drive wheel was rotated to move the solvent around.

  5. 5. BRAKE DRUM OFF: with a proper brake wrench the 4-square brake adjusting screw was backed of and light taping on the bottom of the drum cracked the rust. The drums came off once they started to move. This exposed the workings of the brakes. Both drums need re-grinding.

  6. 6.REMOVING BRAKES: you’ll see the brakes are free-floating and held in place only by two springs, the wheel cylinder and the adjusting cylinder. The spring come out by gently hammering the top of the spring tip that is exposed to the front backwards. A small screw driver was used to push the spring the remaining distance out. This was done on both brakes and they fell apart leaving only the wheel cylinder and adjusting cylinders to go.

  7. 7.DISMANTLING THE WHEEL CYLINDER: required releasing the emergency brake lever from its linkage at the back of the brakes and brake line. The wheel cylinders have a flat spring system that keeps them positioned. The flat spring is slotted and fits snug to the wheel cylinder at the rear of the brake. With the brake line disconnected I worked the springs apart by brute force, but once out, you see how they should actually be removed. Simply lift the top edge of the spring away from two metal turned up tabs and tap the spring out from the top. A flat screw drive placed against to top side of the spring and light tapping with a hammer pushed them apart. Once the flat springs are removed the wheel cylinder comes out.

  8. 8.DISMANTLING THE ADJUSTER CYLINDER: this was a bear and required patience and lots of WD40. However, they come. The adjuster is held to the back of the brake panel by two bolts. To remove the bolts have to come off, but I only moved them out far enough to protect the top of the bolts while I tapped the tops of the bolts so as to loosen the adjuster. This took two sessions at the shop. Once a hairline crack appeared where the adjuster sits against the brake back plate I knew the adjuster would come. Patience, is the word, but helped by a heavy hammer and leaving the nuts on the studs to ensure you do not damage the threads.

  9. 9.REBUILDING WHEEL CYLINDERS AND ADJUSTER: wheel cylinders were “toast” see image, I decided to replace them. The adjusters were a different matter, they cleaned up nicely despite looking pretty rough. Both had one very sticky, hard to budge adjusting block. After soaking a brass drift rod and hammer got both of them out with some good solid heavy strikes. The adjusting rods were lightly rolled over 400 grit wet-dry sandpaper and polished with furniture grade fine-fine steel wool to clean them and the inside barrels of the adjuster.

  10. 10. CLEANUP - DE-RUSTING: final steps include wire brushing the inside and outside of the brake plate and a coat of Trem-Clad paint to reduce rust.