Landoll 317B, Operator'S Manual

Page: 48 / 80

4-5 ELECTRICAL SYSTEM
4-5.1 Maintenance of the electrical system
consists of inspection and minor servicing.
Any wire, connection or electrical component
showing signs of corrosion, wear, breakage
or unraveling must be repaired or replaced.
(See Figure 4-2 for electrical wiring dia-
gram)
4-5.2 Frayed or unraveling wire must have the
defective section removed and replaced with
wire of the same color and gauge. Seal all
connections and insulate.
4-5.3 Corroded terminals must have the corro-
sion removed, source of corrosion neutral-
ized and the terminals resealed, protected,
and insulated.
4-5.4 Fuse or circuit breaker burn-out or
blow-out usually indicates an electrical
short-circuit, although a fuse can occasion-
ally fail from vibration. Insert a second fuse
or reset the breaker. If this fuse immediately
burns out or the breaker trips, locate the
cause of the electrical short and repair.
4-5.5 A light that repeatedly burns-out usually
indicates a loose connection, poor system
ground, or a malfunctioning voltage regula-
tor. Locate the source of the problem and re-
pair. System grounds must be grounded to
bare metal surfaces. Paint, grease, wax, and
other coatings act as insulators. Replace-
ment lamps must be equivalent to the factory
installed lamp.
4-6 SUSPENSION MAINTENANCE
4-6.1 Spring Suspension
a. Make certain that all springs are properly lo-
cated on the wear pads. Twisted springs or
cocked hangers will cause uneven spring
contact with wear pad and will result in exces-
sive wear on the spring suspension. Check
the shocks for excessive wear.
b. Replacing the equalizer bushings and the
torque arm bushings on the spring suspen-
sion is a complex operation and should be left
to trained service personnel. If the bushings
need to be replaced contact a Landoll author-
ized service center or the Landoll factory for
servicing.
4-6.2 Air Ride Suspension
a. Physically check all nuts, bolts, and air line
fittings for proper torque (see torque chart be-
low).
AIR SUSPENSION TORQUE CHART
Size 1-1/8”-7 1/2”-13 *3/4-16 3/4”-10
Torque in
Ft. Lbs.
800 35 35 150
* Air Spring Connections Only.
b. Check all other suspension components for
any sign of damage, looseness, wear or
cracks.
c. With trailer on level surface and air pressure
in excess of 65 psi, all air springs should be
of equal firmness. The height control valve on
right side of front axle controls all air springs
on tandem axle suspensions.
d. The height control valve on right side of
center axle controls ride height for all air
springs on triple axle suspension.
4-6.3 Air Ride Height Adjustment . (See Fig-
ure 4-4 for parts identification) .
a. Before adjusting, the vehicle must be empty
with the kingpin at operating height and have
air supplied to the trailer.
b. Disconnect linkage at the control arm and
raise control arm to the “up” position, raising
the trailer until a block can be placed between
axle tube and undercarriage frame (See Fig-
ure 4-4).
c. Position the wood block between the axle
tube and frame according to table below.
Block height is dependent upon suspension
ride height and/or axle brake size.
4-10