MCi Crusader II 1989 Maintenance Manual page 77

Date 1-1-89 ·
Page ·_. __ 3 -_ 5 _ _
MC-9 MAINTENANCE MANUAL
FILAMENT
Like the washer. a wide variety of filaments can be employed
for washing. Although expensive and hard to get, Tampico fiber
is one of the best Filament having a high wax content (i.e .•
certain polyethylenes) should be avoided since the wax depos-
its on windows and painted surfaces. Polypropylene is normally
satisfactory and may be flagged for optimum performance.
Synthetic filament is normally supplied as an "X" cross•
sectional shape. Since this type of cross-section can trap grit
against the side, it is recommended that filament of a round or
circular cross-sectional shape be used. Filament suppliers
make round filament available upon request
Brush pressure (see below) and amount of filament in con-
tact with the coach are the two factors most damaging to win-
dows of Lucite SAR and to painted-coach surfaces. It is most
important that no more than six inches of filament overlap the
bus side as the brush turns. The less filament in contact with
Lucite SAR, the better the guard against scratches during
cleaning. It may be necessary to provide a soft roller or wheel
guide on the brush arm to prevent over-engagement of bus and
brush.
BRUSH PRESSURE
Normally, the amount of filament in contact with the window
and brush pressure are directly proportional to one another. As
brush pressure is lowered, the amount of filament in contact
with the window is less. Total pressure should be as low as
possible. Again, the wheel concept outlined above can be used
to prevent excessive brush contact
Many washers, particularly those with "wrap-around" fea-
tures, are deisgned with more than one set of side brushes.
Since abrasion occurs when brushes contact the coach, it is
important to minimize exposure of the windows to brushing.
Therefore, it is recommended that one set of brushes be deacti-
vated from the side washing function.
Where two sets of side brushes are deemed necessary, it is
especially important that they be properly adjusted and main-
tained to minimize abrasion potential.
LUBRICATING SPRAY AT
BRUSH/WINDOW INTERFACE
Spray in this area must effectively lubricate the brush/ coach
interface. Since this is the point of greatest mechanical agita-
tion (and. therefore, greatest potential for scratching), lubrica-
tion at this point is essential. We recommend installation of a
spray line to provide lubrication directly at the brush/coach
interface rather than wet the bus or brush independently. A high
lubrication detergent should be usl'd along with warm water. If
desired, this spray line can be used for the window area only.
RINSE SPRAY
Many washers already include a rinse spray to clean grit
from the brush. This should be retained and its position opti-
mized to do the most effective job. The final rinse should be a
high pressure, high volume (with emphasis on the high volume)
rinse with a minimum delivery of 125 GPM (4731/minute).
VEHICLE SPEED
Speed of the coach through the prewash, wash and rinse
should be one to two MPH (1.6.-3.2 KPH). The bus shoulcl never
be stopped while in contact with the brushes.
CLEANING LUCITE® WINDOWS
Conventional techniques may be used to clean Lucite®
S-A-R. However. care should be taken to use a clean. soft
(unsized)·cloth. The surface of the window should be wetted
with the cleaning solution before wiping. When oily surface
contamination is present. the cleaning solution may not wet the
surface thoroughly until it is rubbed with the cloth.
Household cleaners which have be'en tested and found
effective in cleaning Lucite® S-A-R include Easy-Off. Windex.
Glass Plus. Top Job, Mr. Clean and Fantastik. Industrial clean-
ers effective on the acrylic windows are Neleco Subway Soil
Solvent (Neleco Products. Inc.) and C-1102 Alkaline Cleaner
(DuBois Chemicals).
To remove paint, ink marks and graffiti which are resistant to
household cleaners, use a soft cloth saturated with isopropanol
or an aliphatic hydrocarbon solvent Do not use abrasive
cleaners. Avoid using razor blades or other sharp instruments
which might gouge the surface.
Two commercially available anti-static cleaners which effec-
tively clean Lucite® S-A-R windows and reduce the tendency
for static charge build-up are "Like-Magic" Type Nl-5, Mer-
chandise Presentations. fnc .. 3960 Merritt Avenue. New York.
NY 10466 and "Trend" Antistat Cleaner. Dawn Products, P.O.
Box 24. Englewood. Cqlorado 80110. Follow the manufactur-
ers' instructions when using the antistatic cleaners.
REPAIR
The following information concerns acrylic windows which
have been damaged byen lightly coated with conventional
automobile paste wax and polished with an electrically oper-
ated buffing pad. Do not use a cleaner/polish (wax) since the
fine abrasives in such compounds will scratch the surface of
the window.
When buffing. speed and pressure are critical factors. The
acrylic must not be overheated; the buffing wheel should be
kept in constant motion across the window surface to prevent
overheating.
Deeper or wider scratches may be made less offensive by
applying acrylic lacquer directly on the scratch. Such a coating
may be based on EVALCITE® 2041 acrylic resin. Solvents
should be toluene and xylene in a 75/25 blend, although this
ratio may be changed to adjust drying time.
WARNING: Toluene and xylene are hazard-
ous materials. Read and follow all precau-
tions on containers. Use of a proper
respirator is recommended to avoid breath-
ing vapors. Adequate ventilation should be
provided. Protect eyes and skin from
contact with these solvents.
The prepared lacquer may be applied with an artist's paint
brush (natural bristle only) or from a glass (not plastic) syringe.
For assistance in preparing such a lacquer. you may want to
contact a local paint company.