11.22.03.05

.05 Brake Systems — Hydraulic and Vacuum.

A. Parking Brakes.

Procedures: Reject Vehicle If:
(1) Apply parking brake using driver's manual control. (1) Application of parking brake fails to hold the vehicle stationary.
(2) Application. (2) Parking brakes do not fully apply and release when driver's control operated.
(3) Control accessibility. (3) Parking brake control cannot be reached from driver's seat.
(4) Holding power. (4) Operating mechanism fails to hold brakes in applied position without manual effort.
(5) Mechanical components. (5) Any component is seized, missing, incorrectly installed, loose, broken, or worn to such extent as to restrict the effectiveness.

B. Brake Lines and Hoses. Visually inspect:

Procedures: Reject Vehicle If:
(1) Lines and hoses. (1) Any line is cracked, chafed, flattened, insecurely mounted, restricted, any repairs other than steel tubing (tubing connections shall be double flared), leaking, or welded.
(2) Master cylinder. (2) Master cylinder leaks, is loose, or fluid level below 1/2 inch of top.
(3) Cap. (3) Cap is missing, vent holes are plugged, or gasket missing or damaged.

C. Brake Failure Indicators. Visually inspect:

Procedures: Reject Vehicle If:
(1) Warning indicator. (1) Lamp fails to operate when ignition switch is in start position, or lamp operates continuously.
(2) Pressure differential switch. (2) Lamp comes on with engine running and brake pedal depressed as hard as possible.

D. Brake Pedal Reserve and Leakage Test. Without pumping or repeated brake pedal applications, apply a moderate foot force to pedal and maintain for 1 minute. Inspect:

Procedures: Reject Vehicle If:
(1) Leakage. (1) Pedal moves slowly in applied direction.
(2) Travel. (2) Depressed height is more than 75 percent of total possible travel or does not meet manufacturer's specifications.
(3) Pedal pad. (3) Pedal pad is loose, broken, or missing (if fitted by manufacturer).

E. Hydraulic System with Hydraulic Assist. Vehicles equipped with an electrically driven hydraulic pump that functions in the event of a power steering failure may be checked by applying pressure on the brake pedal and turn the ignition switch from "off" to "on" position.

Procedures: Reject Vehicle If:
(1) Apply moderate pressure to brake pedal and turn ignition switch on and off. (1) No assist in service brakes is detected.
(2) Visually inspect brake warning indicator (if applicable). (2) Brake warning indicator fails to function when assist pump is not operating.

F. Vacuum System.

Procedures: Reject Vehicle If:
(1) Visually inspect lines, hoses, clamps, and connections. (1) There are any missing, broken, collapsed, chafed lines, hoses, clamps, or connections.
(2) Visually inspect vacuum tank. (2) Tank is leaking, loose, or damaged.
(3) Clamps. (3) Any clamp is loose, missing, or broken.

G. Power Brake Operation.

Procedures: Reject Vehicle If:
(1) With engine off, deplete all vacuum from system. Apply moderate pressure to brake pedal and start engine. (1) Brake pedal does not move downward when engine is started.
(2) Visually inspect brake booster. (2) Booster is loose or damaged.

H. Vacuum Reserve.

Procedures: Reject Vehicle If:
(1) Start engine and build full vacuum. Shut off engine and make one brake application. (1) Reserve is insufficient to make one full brake application.
(2) Inspect operation of low vacuum indicator. (2) Indicator fails to operate when system is reduced to 8 inches Hg vacuum.

I. Vacuum Pump (if Applicable).

Procedures: Reject Vehicle If:
(1) If the system is not equipped with a vacuum gauge, attach a gauge between the pump and reservoir and operate the pump. If the system also uses engine vacuum, disconnect and plug engine vacuum source. (1) Vacuum pump is not capable of maintaining 18 inches Hg vacuum.

J. Drum Brakes—Hydraulic.

Procedures: Reject Vehicle If:
(1) Apply a moderate force to the brake pedal for 1 minute. Then check all brake drum and backing plate exterior edges for evidence of brake fluid, oil, or grease leakage. (1) Brake fluid, oil, or grease is evident at exterior edge of any backing plate or brake drum.
(2) If the backing plate or brake drum has inspection holes, visually inspect thickness of brake lining. (2) The brake lining thickness appears to be 1/16 inch or less.
(3) Visually inspect exterior surfaces of backing plates for damage. (3) Any backing plate is bent or damaged.
(4) Visually inspect brake drums for cracks. (4) Any brake drum is cracked.
(5) Removal of all wheels and brake drums on an axle is only required when a rejection occurs under žJ(2). Otherwise only remove the wheel and brake drum for the wheel where the defect is suspected. When wheels and brake drums are removed, perform the inspections specified in žJ(6)—(10). (5) (Rejection not applicable in this step)
(6) Bonded Lining.
(a) Measure thickness of lining at thinnest point.
(b) Inspect lining condition.
(6)
(a) Thinnest point of remaining bonded lining is 1/16 inch or less.
(b) Bonded lining is broken, cracked, loose, missing, wear is extremely uneven, or lining is contaminated with oil, grease, or brake fluid.
(7) Riveted Lining.
(a) Measure thickness of lining at thinnest point above rivet head.
(b) Inspect lining condition.
(7)
(a) Thinnest point of remaining lining above a rivet head is 1/16 inch or less.
(b) Lining or rivet is broken, cracked, loose, missing, wear is extremely uneven, or lining is contaminated with oil, grease, or brake fluid.
(8) Mechanical Components.
(a) Visually inspect self-adjusters.
(b) Visually inspect self-adjuster cables or mechanisms.
(c) Anchor pins and hold-down springs.
(d) Visually inspect backing plate.
(8)
(a) Self-adjuster is missing, seized, inoperable, not for proper side of vehicle, or extremely worn.
(b) Cable or mechanism is missing, broken, loose, or inoperable.
(c) Any pin or spring is missing, broken, loose, or extremely worn.
(d) Backing plate is worn, bent, or damaged to prevent free movement of brake shoes.
(9) Wheel Cylinders.
(a) Inspect for operation.
(b) Inspect for leaks.
(c) Inspect dust seals.
(9)
(a) Any wheel cylinder fails to operate.
(b) Any cylinder leaks.
(c) Any dust seal is missing, damaged, or deteriorated.
(10) Brake Drums.
(a) Visually inspect for damage and cracks.
(b) Measure inside diameter of drum for wear and remachining.
(10)
(a) Any drum contains cracks in the friction surface which extend to the outer edge of the bore, or any drum contains any external cracks.
(b) Any combination of wear and remachining exceeds the brake drum manufacturer's limits. If a limit is not available, the maximum combination of wear and remachining may not exceed 0.090 inch greater than the original inside diameter of the drum if the original diameter of the drum is 11 inches or less. For drums greater than 11 inches inside diameter, the maximum wear and remachining may not exceed 0.120 inch greater than the original inside diameter.

K. Disc Brakes — Hydraulic.

Procedures: Reject Vehicle If:
(1) Apply a moderate force to the brake pedal for 1 minute. Then check all calipers and rotor (disc) surfaces for evidence of brake fluid oil, or grease leakage. (1) Brake fluid, oil, or grease is evident or visible on accessible surfaces of any caliper or rotor (disc).
(2) If brake linings are visible, visually inspect thickness of lining. (2) Brake lining thickness appears to be 1/16 inch or less.
(3) If rotors (discs) are visible, visually inspect for cracks or damage. (3) Any rotor (disc) is cracked or damaged.
(4) Removal of all wheels on an axle is only required when a rejection occurs under žK(2). Otherwise remove only the wheel where the defect is suspected. When wheels are removed, perform the inspections specified in žK(5)—(8). (4) (Rejection not applicable in this step)
(5) Bonded Linings.
(a) Measure thickness of lining at thinnest point.
(b) Inspect lining condition.
(5)
(a) Thinnest point of remaining lining is 1/16 inch or less.
(b) Bonded lining is broken, cracked, loose, missing, wear is extremely uneven, or lining is contaminated with oil, grease, or brake fluid.
(6) Riveted Lining.
(a) Measure thickness of lining at thinnest point above rivet head.
(b) Inspect lining condition.
(6)
(a) Thinnest point of remaining lining above a rivet head is 1/16 inch or less.
(b) Lining or rivet is broken, cracked, loose, missing, wear is extremely uneven, or lining is contaminated with oil, grease, or brake fluid.
(7) Calipers. Visually inspect leaks, operation, and anti-vibration components. (7) Caliper is leaking, fails to operate, or piston is seized.
(8) Rotors (Discs).
(a) Visually inspect for damage and cracks.
(b) Measure thickness of rotor for wear and remachining.
(8)
(a) Any rotor is broken, cracked into the hub, or friction surface cracks extend to the periphery of the rotor.
(b) Any combination of wear and remachining reduces the thickness of the rotor to less than the minimum thickness established by the manufacturer or that stamped on the rotor.

L. Brake Lines and Hoses — Hydraulic.

Procedures: Reject Vehicle If:
(1) Visually inspect lines and hoses for condition, mounting, restrictions, and proper material and repair. (1) Any line or hose is leaking, cracked, chafed, flattened, restricted, welded, insecurely mounted, replaced with other than steel tubing, or connections are connections are not double flared.

M. Master Cylinder. Visually inspect master cylinder for:

Procedures: Reject Vehicle If:
(1) Fluid level. (1) Any reservoir fluid level is more than 1/2 inch below top of reservoir.
(2) Leaks. (2) There is evidence of a fluid leak.
(3) Damage. (3) There is evidence of damage.
(4) Mounting. (4) Master cylinder is not securely mounted.
(5) Cap. (5) Cap is missing, has plugged vents, or gasket is missing or damaged.