25
STOP ARMS
Stop arms are required on Blue Bird TC/2000 school buses per FMVSS 131. Stop arm assemblies are
purchased as a kit; many different kits are available with blades to meet all state requirements. The stop arm
is located on the left-hand side of the body under the driver’s window. Stop arms are most commonly oper-
ated by a manual switch located in the switch panel.
For air stop arms the manual switch activates an electric solenoid valve controlling the flow of air. Op-
tionally, the solenoid valve may be activated by the warning lamp system. This system works in conjunction
with the air system on the chassis. No preventive maintenance procedures are required with these systems.
With the electric stop arms the manual switch activates the control relay of the stop arm. Optionally, the
stop arm may be activated by the warning lamp system. The following preventive maintenance procedures
should be followed for the electric stop arm.
Monthly
•
Oil the dual-action breakaway hinge at four (4) pivot
points with a high performance, penetrating lubricant. Tri-
Flow
TM
(DuPont) with teflon is recommended.
•
Check and make sure breakaway portion of hinge is free
and movable.
•
Check fasteners for tightness.
Quarterly
•
Remove front and rear covers of base and check internal
fasteners for tightness.
On units equipped with air stop arms, the air pressure may occasionally require adjustment to insure
proper opening and closing of the stop arm. Air regulator is accessible by opening the electrical panel door
outside under the driver's window. Regulator is identified as shown. To regulate the air pressure, remove the
wire retaining clip below the regulator knob and pull the red lock ring out. Turn the knob counterclockwise to
decrease the pressure, then slowly increase the pressure (turn knob clockwise) until the stop arm hinge is
extended to approximately 90 Degrees. Relock knob by pushing in the red lock ring and reinstalling wire
retaining clip.
The "STOP" sign must extend and if equipped with lights, the lights must be operating at anytime the red
lights of the warning light system are flashing. There are some unique, state-designed warning light/stop
arm systems that permit the stop arm to be withdrawn while warning lights are in operation. For those
situations an audible alarm sounds to alert the driver of the condition.
AIR STOP SIGNS AND CROSSING ARM TROUBLESHOOTING
AIR STOP SIGNS AND CROSSING ARMS
Problem:
Signs won’t open to 90 Degrees.
Areas to Check:
1. Faulty diaphragm - same as above.
2. Faulty solenoid valve - same as above
3. Air pressure regulator - air pressure regulator must precede the solenoid to prevent damage to the
solenoid or to the diaphragm. Excessive pressure may cause damage to both the solenoid and the
diaphragm. Pressure should not exceed 12 lbs.
AIR REGULATOR
Содержание TC/2000
Страница 1: ...Owner s Manual TC 2000 ...
Страница 3: ...2 ...
Страница 106: ...105 NOTES ...
Страница 111: ...Part Number 1919331 Blue Bird Corporation P O Box 937 Fort Valley GA 31030 ...