Section Il. RUSTPROOFING PROCEDURES
12-2. Rustproofing Procedures.
Do not spray any portion of moving compo-
nents, transmission, transfer case, cylin-
ders, pumps, valves, prop shaft, exhaust
system, rubber bump stops, brakedrums,
brake backing plates, parking brake linkage,
shift linkage, tires, electrical components,
engine linkages, or air intake systems. Cov-
er all areas with paper where necessary.
There are areas where a 10 mil wet film
thickness cannot be obtained without wast-
ing a large amount of compound. In those
areas, complete coverage of the surface
area is necessary at whatever thickness is
Figure 12-2. Rustproofing Underbody.
a. Dry Film Thickness Requirements, A five mil dry
b. Check wet film thickness with a wet film
film thickness is required for adequate rustproofing
protection. A 10 mil wet film thickness is required to
of 10 roils is required. In areas where a wet film
obtain a minimum five mil dry film thickness. If
thickness of 10 roils cannot be obtained or where
needed, the vehicle can be resprayed to reach proper
thickness cannot be measured, inspect for complete-
ness of coverage.
b. Spraying Pressure. The rustproofing compound
c. Check all drain holes to ensure that they are
should be applied to sheet metal and structural
members in even coats. Spraying pressure should be as
low as possible while maintaining an even spray pattern.
An acceptable starting point is 40 psi (276 kPa), but
adjustments may have to be made, due to temperature
changes and differences in rustproofing compound.
Using too much pressure will waste compound by
causing overspray and excessively thick coatings.
short rigid tool to completely cover the vehicle
underbody, including open access surfaces on side,
cross, and longitudinal sills.
12-3. Rustproofing Inspection.
Check the vehicle to ensure that all areas requiring
rustproofing compound have been properly and
a. Check seams, welds, corners, and boxed areas to
Figure 12-3. Film Thickness Gage.
ensure that they are adequately coated.