Dry cleaning solvent (PD-680) is both toxic and
flammable. Avoid prolonged breathing of vapors. Avoid
skin contact. Use only in a well ventilated area.
Keep away from open flame. Flash point of solvent is
a. Clean brake drum (1, fig. 5-8) with dry cleaning solvent (PD-680).
Replace, if necessary.
Check brake drum (1) for wear, cracks or damage.
Slight scoring conditions can be corrected by polishing
with crocus cloth. Heavy scoring and out-of-round
conditions require turning brake drum on a refinishing
Whenever the drum on one side of the axle is
refinished, the other drum on that axle should be
turned to the same specifications.
c. Check inner braking surface (2) for heat checking, scoring or warpage.
Using micrometer, check inside of brake drum for out-of-round or tapered
Checking Brake DRUM for Out-of-Roundness
Record each reading. The maximum difference between the four readings cannot
exceed 0.0006 inch (0.01524 mm). Drums with out-of-round exceeding limits must be
Wear welding mask, gloves, and apron when welding or
using cutting torch. Failure to wear adequate
protective clothing may result in serious injury.