Servicing drum brakes is a relatively easy task for the DIY mechanic, but it can sometimes be frustrating to get all of the bits and pieces back together again. One common problem faced by inexperienced mechanics is getting the drum to fit back on over the new shoes. The new shoes have thicker linings than the old shoes; and if the shoe position is not properly adjusted before trying to reinstall the drum, then the drum might not fit over the shoes. Fortunately, the fix is relatively simple.
Measure the inside diameter of the brake drum with a brake shoe adjustment gauge. Place the inside jaws of the gauge into the drum and move the jaws outward until they contact the inner drum surface. Note the drum diameter measurement and tighten the locking knob to hold the gauge in that position.
Move the gauge over to the brake shoe assembly and place the outside jaws over the shoes. The diameter formed by the shoes will not fit inside the jaws, but this will give you a visual indication of how much you need to adjust the shoes.
Move the adjuster pawl (ratchet) lever out of the star wheel teeth and rotate the star wheel so that it becomes shorter. This will allow the brake shoes to come closer together. Turn the star wheel three or four rotations then release the pawl. Check to see if the brake shoes fit within the outside jaws of the brake shoe adjustment gauge. If not, repeat the procedure. If the shoes do fit inside the gauge, then install the drum to complete the job.
