Skylark L4-144 2.4L DOHC VIN T SFI (1997)
Brake Drum: Service and Repair
Refinishing
NOTE: If a drum must be refinished, remove only enough metal to obtain a true, smooth braking surface. If a drum does not clean-up when refinished to
less than or equal to the maximum re-bore diameter, as shown in Specifications, replace it. Removal of more metal will affect heat dissipation and may
cause drum distortion.
MAXIMUM DIAMETER
All brake drums have a maximum diameter cast into them. This diameter is the maximum wear diameter and not a finish diameter. When
refinishing a brake drum, resurface the drum to no more than a dimension of 0.76 mm (0.030 inches) less than the discard diameter. The refinish
diameter is the maximum diameter the brake drum may be refinished to and still allow safe braking action. If this dimension is exceeded, the brake
drum will wear beyond the discard diameter during normal brake wear.
USE PROPER EQUIPMENT
Always use sharp cutting tools or bits. Dull or worn tools leave a poor surface finish which will affect initial braking performance. Always use
vibration dampening attachments when refinishing braking surfaces. These attachments eliminate tool chatter so a better finish can be obtained.
MACHINE SPEED
The optimum speed for refinishing braking surfaces is a spindle speed of 150 rpm. Crossfeed for rough cutting should range from 0.15-0.25 mm
(0.006-0.010 inches) per revolution. Finish cuts should be made at crossfeeds no greater than 0.05 mm (0.002 inches) per revolution.
