When working on or around a vehicle, the following general precautions should be observed at all times:
A. Park the vehicle on a level surface, apply the parking brakes and always block the wheels.
B. Always wear safety glasses and other appropriate safety gear.
C. Stop the engine and remove ignition key when working under or around the vehicle.
D. When working in the engine compartment, the engine should be shut off and the ignition key should be removed. Where circumstances require that the engine be in operation, EXTREME CAUTION should be used to prevent personal injury resulting from contact with moving, rotating, leaking, heated or electrically charged components.
BODY EXTERIOR
A. Visually inspect the body exterior to ensure that there is not any panel, rub rail or trim that is loose, torn, dislocated or protruding from the surface of the bus that would create a hazard.
B. All engine, battery or other doors must be securely mounted and properly installed.
BODY INTERIOR
Aisle
A. Visually inspect the aisle to ensure that all aisles, including aisle (or passageway between seats) leading to emergency door are a minimum of 12 inches.
B. Visually inspect to ensure that there are no obstructions in an aisle that would prevent passengers from egress to emergency exits.
C. On school buses with a side emergency door, check that aisle space from center aisle to side of emergency door is 12 inches by measuring between the vertical line of the seat back and the face of the next seat cushion or bottom of a flip seat.
D. On buses equipped with flip up seats, inspect to ensure the seat cushion rises to a vertical position automatically when not occupied.
Door, Entrance
Visually inspect and operate entrance door and inspect door to properly open and close without any obstruction of movement. Inspect manually operated door to make sure door will maintain an open and closed position. Door shall not have any locking device except for interlock systems. On power-operated entrance doors, the emergency release valve, switch or device to release the entrance door must be placed above or to the immediate left or immediate right of the entrance door and must be clearly labeled.
Floor
Visually inspect floor covering, aisle and cove molding strips for condition and adhesion. Check fastening holes for cracks, and check condition of rubber in aisle to ensure that there are no unsealed holes or cracks through the underside of the bus and that there is no damage to the coverings which could cause a trip or slip hazard.
Handrail
Handrail must be securely mounted and all OEM hardware present. Perform the NHTSA Nut and String Test as described and illustrated below.
Nut and String Test
The Handrail Inspection Tool and Procedure
The inspection tool is inexpensive and the procedure for detecting potentially fatal handrail designs is quite simple. The inspection tool is a standard 1/2 inch hex nut measuring 3/4 inch across the flats. This nut is tied to 1/8 inch thick cotton cord measuring 36 inches in length with overhand knots. The drawstring should have a minimum length of 30 inches, when tied to the nut and attached so that a pull of at least 10 pounds does not separate the nut from or break the drawstring.
Steps to conduct a handrail inspection are:
* Stand on the ground outside of the bus;
* Drop the inspection tool between the handrail and step well wall, simulating the typical way students exit the bus;
* Draw the inspection tool through the handrail in a smooth, continuous slow motion; and
* Repeat this procedure several times (minimum of three times).
Note: It is important to drop the inspection tool over the handrail in such a way as to simulate a child exiting the bus. This is a drop-and-drag test. Do not create a snagging situation by placing the nut in an area that would not be exposed to a drawstring or other articles.
Inspection Results
Take the bus out of service and repair it if the inspection tool catches or snags anywhere on the handrail. If the nut separates from the drawstring or the drawstring breaks, reassemble the tool and retest. If the inspection tool pulls freely without catching or snagging, the bus should not be rejected.
Panels
Visually inspect all interior sidewall, rear, ceiling and driver's area paneling for secure fastening, projections or sharp edges and general condition.
Seat(s) and Barrier(s)
A. Visually inspect all seats and barriers to ensure that all are securely mounted and not loose or broken.
B. All seats shall be forward-facing and securely fastened to the bus body. Passenger seat cushions shall be fastened to prevent the cushions from disengaging from the seat frames in the event of an accident. There shall be a minimum space of 24 inches between the forward surface of a seat back and the rear surface of the seat or barrier ahead measured across the seat cushion without depressing any surface. The forward surface may have side bolsters that briefly reduce the width to less than 24 inches provided the remainder of the seat measures at least 24 inches.
C. Seats and barriers should appear symmetrical. Seats/barriers that do not appear symmetrical should be physically inspected to ensure seat covering and/or padding is not significantly compromised and complies with FMVSS 571.222.
Seat, Driver
A. Visually inspect driver's seat to ensure that it is securely fastened to the vehicle.
B. Visually inspect the driver's seat for its ability to maintain the adjusted position. Inspect driver's restraining device (seat belt) for fraying, attaching hardware and the capacity of the seat belt for maintaining the driver in the seated position.
Stepwell
Visually inspect the stepwell for the condition of support structure to ensure structural stability. Inspect stepwell treads to ensure proper securing and adhesion to stepwell. Visually inspect step treads for any excessive worn areas that may pose a tripping or slip hazard.
BRAKE SYSTEMS
Air System
A. With full system air pressure, depress the brake pedal and inspect each wheel end brake to determine if effective braking forces are applied to each wheel end brake. There should be no audible air loss at supply lines, fittings, valves or brake chambers.
B. With full system pressure, make a single full service brake application with the parking brake and ignition off. Note the gauges and listen for air leaks. Release the service brake.
C. If an air leak is detected at any point in the inspection process, the inspector should check the vehicle's air loss rate following these procedures:
1. Set engine at idle and release brakes;
2. Reduce air pressure in reservoir to 80 psi;
3. Make a full brake application with governor cut-in; and
4. Check air pressure gauge after initial application for air loss. Air pressure should be maintained or increase. A drop in pressure indicates a serious air leak in the brake system.
Air Brakes Measurement
The following procedure is based on the applied stroke method for measuring the movement of the brake chamber push rod:
A. Release the spring brakes and visually check each brake to ensure that it is in the normal released position.
B. With the brakes released, make a mark where the pushrod exits the brake chamber.
C. With the engine off, make a series of brake applications to reduce the reservoir pressure to between 90 to 100 psi.
D. Apply and hold a full brake application (90 to 100 psi).
E. Measure the distance between the mark and the face of the brake chamber. The difference between measurements is called the chamber applied stroke.
Note: Any brake that is beyond the re-adjustment limit will require repairs and/or adjustment. (See Table 1: Brake Adjustment Specifications below.)
Table 1: Brake Adjustment Specifications
Brake adjustment: Shall be less than those specifications contained herein relating to "Brake Adjustment Limit."
(Dimensions are in inches.)
CLAMP TYPE BRAKE CHAMBER DATA | ||
Type | Outside Diameter | Brake Adjustment Limit |
6 | 4 1/2 | 1.25 |
9 | 5 1/4 | 1.375 |
12 | 5 11/16 | 1.375 |
16 | 6 3/8 | 1.75 |
20 | 6 25/32 | 1.75 |
24 | 7 7/32 | 1.75 |
30 | 8 3/32 | 2 |
36 | 9 | 2.25 |
"LONG STROKE" CLAMP TYPE BRAKE CHAMBER DATA | ||
Type | Outside Diameter | Brake Adjustment Limit |
12 | 5 11/16 | 1.75 |
16 | 6 3/8 | 2.0 |
20 (2 1/2" Rated Stroke) | 6 25/32 | 2.0 |
20 (3" Rated Stroke) | 6 25/32 | 2.5 |
24 (2 1/2" Rated Stroke) | 7 7/32 | 2.0 |
24+ (3" Rated Stroke) | 7 7/32 | 2.5 |
30 | 8 3/32 | 2.5 |
DD-3 Brake Chamber Data | ||
Type | Outside Diameter | Brake Adjustment Limit |
30 | 8 1/8 | 2.25 |
Note: This chamber has three air lines and found on motorcoaches. |
Wedge Brake Data |
The combined movement of both brake shoe lining scribe marks shall not exceed 1/8 inch ( 3.18mm). |
Brake Shoe/Pad/Lining
A. Visually inspect all brake linings/shoes/pads. Linings may be checked through inspection slots. All shoes/pads/linings shall comply with the applicable standards.
B. The brake lining/pad thickness shall not be less than 3/16 inch at the shoe center for a shoe with a continuous strip of lining, less than 1/4 inch at the shoe center for a shoe with two pads, or worn to the wear indicator if the lining is so marked, for air drum brakes.
C. The brake lining/pad thickness shall not be less than 1/8 inch for air disc brakes, or 1/16 inch or less for hydraulic disc brakes.
D. Visually inspect the brake lining/pad to ensure that it is firmly attached to the shoe, is not cracked or broken, and that the friction surface is not saturated with oil, grease, or brake fluid.
E. Visually inspect all brake components mounting hardware for any loose, cracked, broken or missing items. This inspection should be performed with the brakes released and with the brakes applied. It may be necessary to remove inspection access covers, brake dust covers or, in some instances, pull wheels and drums to accomplish the inspection.
Chamber Size
Visually inspect all brake chambers to ensure they are properly marked, in good operating condition, have no visible damage, and are properly matched. Chambers must be matched by size, type and stroke.
Drums/Rotors
A. Visually inspect all brake drums/rotors for any external cracks that open when brakes are applied. (Do not confuse short hairline internal check cracks with flexural cracks.)
B. Inspect for any portion of the drum/rotor missing or in danger of falling away.
Note: It may be necessary to remove inspection access covers, brake dust covers or, in some instances, pull wheels and drums to accomplish the inspection.
Hoses and Tubing
A. Carefully perform a visual inspection of all system hoses, lines, and tubing.
B. Inspect all hoses, lines, and tubing for any audible leak (if air), or visible leak (if hydraulic), any bulging/swelling when the system is pressurized, any hose, line, or tubing is cracked, broken or crimped in such a manner as to restrict flow, any hose abraded (chafed) through outer cover to fabric layer or any line/tubing, and for proper securement and support.
Hydraulic Brakes Measurement
A. With the brake pedal in the full upright position, the inspector shall measure the distance between the brake pedal and the floor or firewall. With the engine running, a single firm brake application shall be made and the distance between the brake pedal and the floor or firewall shall be measured a second time. The difference shall be recorded.
B. With vehicle stopped and engine running, depress brake pedal. The system must be able to maintain brake pedal height under moderate foot force (40-60 pounds) for one minute without pumping. With vehicle in stopped position and brake pedal depressed under moderate foot force (40-60 pounds) there should be a minimum of 1/3 of the total available pedal travel (manufacturer's specification) remaining on nonpowered systems.
Hydraulic Brake System
A. With the engine off, turn the ignition switch to the "on" position and check the instrument panel for visible and audible warning signals to indicate system malfunction. If bus is equipped with vacuum assist, it shall have a visible warning signal and gauge to indicate any loss of vacuum. Audible signals must be loud enough to be heard over engine noise.
B. Visually inspect the master cylinder to determine if it is below the minimum fill requirements, is leaking, is loose or improperly mounted.
C. Visually inspect the hydraulic fluid reservoir level in the master cylinder unit. Inspect for any fluid leaks on wheel cylinders/calipers, master cylinders, hose connection and hydrovac and on buses using vacuum-assisted brakes. Check for brake fluid around the brake booster between the booster and firewall.
Parking Brake
A. With the engine operating and the park brakes set, place the transmission in both forward and reverse gears to determine if brakes will hold vehicle stationary.
B. Visually and physically check condition of parking brake system and parking brake warning light.
Pedal Reserve
A. With the brake pedal in the full upright position, the inspector shall measure the distance between the brake pedal and the floor or firewall. With the engine running, a single firm brake application shall be made and the distance between the brake pedal and the floor or firewall shall be measured a second time. The difference shall be recorded.
B. With vehicle stopped and engine running, depress brake pedal. The system must be able to maintain brake pedal height under moderate foot force (40-60 pounds) for one minute without pumping. With vehicle in stopped position and brake pedal depressed under moderate foot force (40-60 pounds) there should be a minimum of 1/3 of the total available pedal travel (manufacturer's specification) remaining on nonpowered systems.
Power Assist Unit
A. Electric/Hydraulic Assist: With engine off, depress the brake pedal. The electric/hydraulic brake assist motor must operate.
B. Hydrovac Assist: With engine off, the driver shall pump the brakes to exhaust all reserve. Hold firm pressure on the brake pedal and start the engine. The pedal should fall slightly. Failure of the pedal to fall slightly indicates a malfunction of the power assist unit.
C. Hydro-boost: After 2-3 brake applications with the engine off, start the vehicle while maintaining pressure on the brake pedal. The pedal should push briefly, and then fall as the power assist engages.
Slack Adjuster Length
Measure from the center of the S-cam to the center of the push rod clevis pin. All slack adjusters on a single axle shall be of the same type and length.
DIFFERENTIAL
The Inspector shall visually inspect the differential and differential housing for cracks and leaks. Careful attention shall be made to the areas of mounting attaching hardware and wheel end areas. Housing vent shall be inspected to ensure that it is not clogged and is functional by twisting the vent cap by hand.
DRIVESHAFT
A. Visually and physically inspect each segment of the driveshaft and associated hardware. Inspect for bends, cracks, missing weights or debris entangled in the shaft. Each shaft more than 18 inches long shall be equipped with a suitable guard to prevent an accident or injury in the event of its fracture or disconnection. The inspector shall check to ensure that the driveshaft guards are not loose, bent or missing.
B. Visually and physically inspect each universal joint and center bearing. The universal joint(s) and center bearing(s) shall not be loose or worn and shall have all attaching hardware securely fastened. The inspector shall check for lateral and vertical movement of the universal joints and center bearing by grasping the universal joint and attempting to move the joint laterally and vertically. Inspector shall inspect universal joints for substandard or welded repairs.
C. Visually inspect driveshaft for proper phasing. (See illustration.)
ELECTRICAL/BATTERY
Battery
A. Visually and physically inspect that the battery(ies) is(are) securely mounted and no signs of leaking, or excessive corrosion.
B. Crank engine to ensure adequate battery capacity to start engine.
Cables
A. Visually inspect all electrical cabling and wiring for chafed, frayed, damaged or burnt insulation.
B. Visually and physically inspect for corroded or loose connections at the battery terminals. Inspect for unsuitable insulation to electrical cabling.
C. Inspect for missing or damaged protective grommets insulating all electrical cables through metal compartment panels. All electrical cabling passing through a metal surface shall pass through an insulated grommet as to provide adequate protection against chaffing and shorting.
D. Visually and physically inspect for any broken or unsecured mounting of electrical components.
E. Visually and physically inspect electrical cabling for securement, routing or any unsecured wiring that may cause chafing or frayed conditions.
Windshield Wipers
Operate wiper and washer system. The wiping system should be power-driven with at least two speeds and should be able to clean the area of the windshield within the wiping pattern. Wipers should operate with a minimum of 45 cycles per minute.
EMERGENCY EQUIPMENT
A. Visually inspect that the fire extinguisher is readily accessible to the driver and passengers, that it is fully charged of proper type and size, is properly secured and has a working pressure gauge.
B. Visually inspect any other state-required equipment such as first aid kits, body fluid kits, webbing cutters and emergency reflectors and ensure that these items are fully stocked, functional and properly secured.
EMERGENCY EXITS
A. Visually inspect all emergency exits.
1. Operate all emergency exits. Exits must open freely and completely.
2. Door prop rods must operate freely and hold door or exit in open position without obstructing exit.
3. There shall be no padlocks or any other locking devices on exits except interlocking systems.
B. Visually inspect all exits to ensure they are clearly labeled and marked on both the inside and outside of the bus.
C. Ensure that all exits have an audible device to alert the driver of an open exit door or window.
Note: FMVSS 571.217 defines the number of exits for each type of bus.
ENGINE
A. Visually inspect engine and surrounding components for evidence of fluid leaks and loose or damaged components. Inspector shall start engine. While engine is operating, inspector shall visually and audibly monitor engine for proper operation, leaks and unusual noises of engine or components.
B. Inspect cooling fan per manufacturer's recommendations.
C. Visually and physically inspect all drive belts for proper alignment and tension per manufacturer's recommendations. All belts shall be free of cracking, frays, fluid, glazing and excessive wear. Inspect belt-tensioner per manufacturer's recommendations.
D. Visually inspect all hydraulic, coolant, fuel and pneumatic hoses for damage, proper routing, proper type and proper securement. Hoses shall be routed in such a way as to avoid contact with exhaust, rotating or moving engine components or sharp edges. Hoses shall not be cracked, leaking, swollen or chaffed.
EXHAUST SYSTEM
A. Visually and audibly inspect the complete exhaust system including muffler, diesel particulate filter (DPF) and diesel oxidation catalyst (DOC) for leaks, restrictions and damage and to ensure that exhaust is not discharging directly below the driver or passenger compartment. All exhaust emission control devices shall be installed and operating per the manufacturer's recommendations.
B. Inspect for the presence and condition of heat shielding over and around all piping, and components where specified by vehicle manufacturer.
C. Visually and physically inspect all exhaust system mounting hardware for loose, missing or damaged components and that it is securely attached. Inspect to ensure that all clamps are in place and secure.
D. Visually inspect exhaust system for indications of, and areas likely to result in, burning, charring or damaging the electrical wiring, the fuel supply or any combustible part of the vehicle.
FUEL SYSTEM
A. Visually inspect all parts of the fuel tank, fuel tank cage and fuel system to include lines, hoses, filters, fill cap and fittings for indications of damage or leaks.
B. Visually and physically inspect fuel lines and hoses for proper securement, routing and missing or loose clamps that may cause chafing or come in contact with electrical components.
LAMPS/SIGNALS
A. Visually inspect all lamps, such as brakes, turn signals, tail, head (low beam), overhead warning lights (amber and red), hazard warning and stop arm lights to ensure proper visibility and operation. Turn signals should flash at a rate of 60 to 120 times per minute.
B. Inspect that the horn functions and is audible from approximately 200 feet away.
C. Inspect the crossing control device, if equipped, for proper operation (e.g., that it extends and retracts as designed).
MIRRORS
Visually inspect all mirrors to identify any mirror that is damaged, clouded or otherwise has an obscured area. All mirrors should hold a set adjustment. All mirrors should be directed to view the intended area for which they are designed.
STEERING SYSTEM
Ball and Socket Joints
A. With the bus on the ground, the inspector shall examine the ball joint nut stud for movement while the steering wheel is being rocked in a back-and-forth action. The inspector shall examine the ball/socket joint for weld repairs.
B. Check for lateral and vertical movement by grasping the tie rod and drag link sockets attempting to laterally and vertically move the ball joint. (Rotational movement will not be considered.) Any motion other than rotational, greater than 1/8 inch that can be detected by movement with two hands with moderate strength in any connecting joint is a defect.
Front Axle Beam
Visually examine the front axle beam for any obvious bend or twist, any cracks, or any welded repair.
Hoses/Fluids
Visually examine the power steering fluid reservoir for proper fluid level. With the system operating, inspect all system components, hoses and fittings for leaks.
Nuts
Visually examine all tie rods, pitman arm, drag link, steering arm and tie rod arm for looseness and missing fasteners.
Pitman Arm
A. While the steering wheel is being rotated in a back-and-forth motion; visually inspect the pitman arm and output shaft connection for looseness at the output shaft joint.
B. The pitman arm shall also be inspected for damage, cracks or welded repairs.
Power Steering
A. The inspector shall manually manipulate the auxiliary power assist cylinder to check for looseness. The inspector shall start the bus and rotate the steering wheel in a back-and-forth action to ensure the power steering pump is operable.
B. With the engine stopped inspect the system drive belt(s) for any fraying, cracks or fluid saturation. Check belt tension. On units equipped with automatic tensioner ensure that tensioner moves freely.
C. Inspect the fluid reservoir while at operating temperature to ensure that the fluid level is not below add mark. Inspect for signs of fluid leakage.
Steering
A. Visually inspect for any modification or other condition that interferes with free movement of any steering component. Turn steering wheel through a full right and left turn and feel for binding or jamming conditions. Both front wheels must be capable of being turned to full right or full left without binding or interference.
B. Inspect turn stops by observing for shiny spots and/or signs of wear due to contact with other vehicle components on the sides of tires, drag links, pitman arm, shock absorbers or brake lines.
Steering Column/Wheel
A. Inspect steering column for any looseness in bolts, clamps, positioning parts or universal joints. Inspect flexible coupling in steering column (if the vehicle is so equipped) for excessive misalignment and tightness of clamp bolt or nut.
B. The steering column and components shall also be inspected for damage, cracks or welded repairs. Inspect steering wheel to ensure that it is properly positioned and secured.
C. Place steering axle wheels in a straight ahead position have an assistant turn the steering wheel until movement is observed at the left road wheel and measure the steering wheel movement from starting position to wheel movement position. Compare this measurement to the applicable listing in Table 2: Steering Wheel Free Play, below.
Table 2: Steering Wheel Free Play
Steering Wheel Free Play: Steering wheel free play shall not exceed the requirements listed in the following chart:
Steering Wheel Diameter | Manual System Movement 30 | Power System Movement 45 |
16" (41cm) | 2" ( 5.1cm) | 4 1/2" ( 11.5cm) |
18" (46cm) | 2 1/4 " ( 5.4cm) | 4 3/4" (12cm) |
20" (51cm) | 2 1/2" ( 6.4cm | 5 1/4" ( 13.5cm) |
22" (56cm) | 2 3/4" (7cm) | 5 3/4" ( 14.5cm) |
Steering Gear Box
A. Visually examine the steering gear box for any loose, damaged or missing mounting bolts. Inspect for cracks in the gear box, mounting brackets or any obvious welded repairs.
B. While having an assistant rock the steering wheel back-and-forth; visually inspect the steering shaft and gear box for any looseness where the steering gear box is mounted to the frame. Visually inspect steering shaft coupler for cracks, damage or looseness.
C. With the engine operating inspect for excessive fluid and/or oil leak (observable movement of fluid).
Tie Rods/Drag Links
A. While having an assistant to rock the steering wheel back-and-forth, visually inspect the tie rod ends, crossbar, and drag links for any looseness at the steering linkage pivot points.
B. Check for lateral and vertical movement by grasping the tie rod and drag link sockets attempting to laterally and vertically move the ball joint (rotational movement will not be considered). Any motion, other than rotational, greater than 1/8 inch that can be detected by movement with two hands with moderate strength in any connecting joint is a defect.
C. Check crossbar for structural damage and crossbar clamps for secure mounting.
SUSPENSION COMPONENTS
Axle Parts/Members
A. Visually and physically inspect all front and rear axle components. Inspect all U-bolts and other suspension to axle mounting hardware for cracks, breaks, looseness or improper type.
B. Inspect axle, axle housing, spring hanger(s), shackles or other axle components for alignment, cracks, breaks and loose or missing items that could result in shifting of an axle from its normal position.
C. Inspect front axle beam for signs of improper repair (e.g., welding or heating).
D. Inspect for any worn (beyond manufacturer specifications) or improperly assembled U-bolt, shock, kingpin, ball joint, strut, air spring or positioning components.
E. Inspect all leaf spring hangers, hanger assemblies or portions of leaf for broken, separated, sagging, bent, abnormally worn (beyond manufacturer specifications), shifted or missing components.
F. Inspect pins and bushings for wear, off-center spring eye, rubbing shackle or nonsymmetric joints. Inspect for any broken, weak or damaged coil spring and mounting assemblies.
G. Visually and physically inspect all hydraulic shock absorbers for leaks, looseness, damage or missing components.
H. Inspect air suspension (if equipped). Observe that the vehicle is lifting level. With the air system fully charged, inspect for any audible or visual air leakage at the air spring assembly, supply hoses and connections.
Caution: Inspector should use caution whenever underneath the vehicle. There may not be sufficient room underneath the vehicle should a problem occur with the air suspension system.
Bumpers
Visually inspect front and rear bumpers for missing attaching hardware or broken hardware. Ensure bumpers are properly mounted and secure and that there is no point protruding beyond the confines of the vehicle so as to create a hazard.
Chassis/Frame/Unibody
A. Visually inspect frame for cracks, loose attaching hardware, sagging, broken, or unapproved welds to frame side rail or flange.
B. Visually and physically inspect for body hold-down components for damage that would permit the shifting of the body.
C. Inspect for cracked, loose, bent, broken or unapproved welds to frame member that affect support of functional components (e.g., steering gear, engine, transmission, body parts or suspension). Welding to frame should be performed only by manufacturer or designee.
Note: Inspect for any crack 1 1/2 inch or longer in the frame side rail web which is directed toward bottom flange or any crack extending from the frame side rail web around the radius and into the bottom flange.
Crossmembers
A. Visually and physically inspect all crossmembers, attaching hardware and other structural supports for cracks or deformations. Visually inspect for three or more adjacent cross members that are missing, broken, damaged or loose.
B. Inspect any area of the floor that is sagging, weak or damaged due to broken, damaged or loose crossmembers.
Outriggers/Body Supports
Visually inspect all outriggers and attaching hardware for cracks, missing bolts and damage.
TIRES/WHEELS/HUBS
Hub & Assemblies
A. Visually inspect kingpin and wheel bearing assemblies for looseness, damage, missing or loose fasteners. This shall include locking pins, draw keys, caps and bearings.
B. Physically inspect kingpin and bearing assemblies for play as follows: with the tire raised off the ground, grasp tire at top and attempt to move the wheel assembly in and out. If movement is present, inspector can help to identify the source by following this procedure:
Have an assistant fully apply brakes while rechecking play. If movement disappears with brakes applied, then play is in the wheel bearings. If movement remains, it is most likely in the kingpin area. Assembly shall not have excessive kingpin play that exceeds .250 inch measured at outside edge of tire or wheel bearing movement that exceeds .010 inch measured at bearing hub.
C. Visually inspect A-frames and bushings on Type A vehicles. Inspect bushings for wear, cracking, splitting, or severe extrusion from suspension parts.
D. For vehicles equipped with "wet hubs" or oil bath hubs the inspector should visually check the site glass for lubricant level.
Tire Inflation
A. Visually inspect that tires are properly inflated and do not have noticeable leaks. (See 393.76(h)(1),(2).) If pressure is questionable, inspector shall use a tire pressure gauge to verify pressure.
B. Visually inspect valve stem for damage and presence of valve cap.
Tire Sidewall
Inspector shall inspect tire sidewall for cuts, wear and any observable bumps or bulges.
Tire Tread Depth
A. Visually inspect for any front tire worn to less than 4/32 inch.
B. Visually inspect for any rear tire worn to less than 2/32 inch.
C. If a visual inspection cannot determine that the tire meets the minimum depth requirement, the inspector shall use a commercial tire depth gauge to verify tread depth.
Tire Type
A. Visually inspect the steer axle (front) to ensure that no recapped, re-grooved tires are present.
B. Visually inspect tires for improper wear patterns. (See Tire Wear Chart below.)
C. Check proper type (i.e., load range, size, mismatched on axle).
Over Inflation: Excessive wear at the center of the tread indicates that the air pressure in the tire is consistently too high. The tire is riding on the center of the tread and wearing it prematurely. Many times, this visual method of inflation (inflating the tires up until there is no bulge at the bottom) is at fault; tire inflation pressure should always be checked with a reliable tire pressure gauge.
Under Inflation: This type of wear usually results from consistent under inflation. When a tire is under inflated, there is too much contact with the road by the outer treads, which wear prematurely. Tire pressure should be checked with a reliable pressure gauge. When this type of wear occurs, and the tire pressure is known to be consistently correct, a bent or worn steering component or the need for wheel alignment could be indicated. Bent steering or idler arms cause incorrect toe-in and abnormal handling characteristics on turns.
Feathering: Feathering is a condition when the edge of each tread rib develops a slightly rounded edge on one side and a sharp edge on the other. By running your hand over the tire, you can usually feel the sharper edges before you'll be able to see them. The most common cause of feathering is incorrect toe-in setting, which can be cured by having it set correctly. Occasionally toe-in will be set correctly and this wear pattern still occurs.
Side Wear: When an inner or outer rib wears faster than the rest of the tire, the need for alignment is indicated. There is excessive camber in the front suspension, causing the wheel to lean too much to the inside or outside and putting too much load on one side of the tire. Misalignment could be due to sagging springs, worn ball joints, worn control arm bushings or worn kingpin bushings.
Cupping: Cups or scalloped dips appearing around the edge of the tread on one side or the other, almost always indicate worn (sometimes bent) suspension parts. Adjustment of wheel alignment alone will seldom cure the problem. Any worn component that connects the wheel assembly to the vehicle (ball joint, kingpins, wheel bearing, shock absorber, springs, bushings, etc.) can cause this condition. Occasionally, wheels that are out of balance will wear like this, but wheel imbalance usually shows up as bald spots between the outside edges and center of the tread.
Wheels/Rims/Spiders
A. Inspector shall inspect all nuts, bolts, studs, lugs and holes for damage. Visually inspect for broken, damaged, missing or loose fasteners. Rust around fasteners or on rim surface is sometimes an indication of cracked or loose mounting hardware.
B. Visually inspect rim for, cracks, welds or broken components. Visually inspect for any lock or slide ring that is broken, cracked, improperly seated, sprung or has mismatched rings.
WHEELCHAIR LIFT-EQUIPPED VEHICLES
A. Visually inspect and operate wheelchair lift to ensure proper function as designed. Inspect for any leaks that would hinder the operation of the lift.
B. Inspect all safety systems of the wheelchair lift (e.g., hand rails, ramp stops, etc.) and ensure that they are functioning as designed and in compliance with FMVSS 403 and 404.
C. Ensure that all pinch points are protected from seated passengers.
D. Visually inspect all wheelchair and occupant securement devices to ensure none are missing or broken and that straps are not frayed.
E. Inspect that all components for each wheel chair position are compatible in accordance with manufacturers' specifications.
F. Visually and physically inspect all anchorage points, tracking and fasteners for securement.
WINDOWS
A. Any glass or glazing that is broken through or missing ( 393.60);
B. Any glass not of approved type [ 393.60(a)];
C. Windshield has discoloration or other damage in that portion extending upward from the height of the topmost portion of the steering wheel, but not including a two-inch border at the top and a one-inch border at each side of the windshield or each panel thereof, except as follows:
1. Color or tint applied by the manufacturer for the reduction of glare;
2. Any crack not over 1/4 inch long, if not intersected by any other crack;
3. Any damaged area, that can be covered by a disc 3/4 inch in diameter, if not closer than three inches to any other such damaged area; or 83
4. Driver's side area window(s) have chips, clouding, or cracks that obscure the driver's vision [ 393.60(c)]; or
D. No operable defrosting and defogging system to clear the driver's windshield ( 571.103).
Neb. Admin. Code EDUCATION, DEPARTMENT OF, tit. 92, ch. 92, app H