11.14.04.06

.06 Exhaust System.

A. The exhaust system includes the exhaust manifold, and all piping leading to and including the muffler, catalytic converter, resonator, and the tail piping.

Procedures: Reject Vehicle If:
(1) With engine running and the vehicle on a hoist, lift, or over a pit, visually inspect the exhaust pipes, mufflers, resonators, and tail pipes for leaks, deterioration, proper mounting, damage and general condition.
 (a) Rusted or corroded areas shall be given particular attention.
 (b) Holes in the system made by the manufacturer for drainage are not cause for rejection.
(1) Vehicle has no muffler.
(2) There are loose or leaking seams or joints.
(3) There are holes caused by corrosion or temporary repairs made to the exhaust pipe, muffler, resonator, or the tail pipe. Welding or brazing is considered a permanent repair if it does not leak.
(4) Tail pipe end is pinched or obstructed or does not extend beyond the passenger or driver area.
(2) The tail pipe shall extend beyond the passenger or occupant compartment and the enclosed cargo area if it is open to the driver or passenger area. (5) The system is not properly mounted, or securely fastened, or if the seam of a muffler or resonator in a school vehicle faces the fuel tank, fuel lines, or floor of the vehicle.
(3) Type I school buses shall have a full length tail pipe extending beyond the rear wheels and exiting beyond the side or rear of the body unless the vehicle is equipped with a left side exhaust system which meets the following criteria:
 (a) The exhaust pipe may not pass within 12 inches of the gasoline tank or its connections unless a suitable baffle is installed between the exhaust system and these components. On vehicles with left side mounted gasoline tanks, compliance with this requirement may be more difficult; however, this requirement shall still be met.
(6) There are loose muffler baffles; the vehicle is equipped with cut-out or similar device; or the system is not original or equivalent.
(7) Any part of the system passes through the occupant compartment, or there are any leaks in the heat exchange boxes or ducts of vehicle using engine exhaust heat to warm the interior of the vehicle.
  (b) No part of the exhaust system may pass within 12 inches of any flexible brake hose or vacuum booster unless a suitable baffle is installed between the exhaust system and these components. (8) The tail pipe does not extend beyond the occupant compartment and the enclosed cargo area if it is open or the occupant compartment.
 (c) The exhaust pipe should be at approximately a 45-degree angle as it approaches the left body line to prevent back pressure and heat buildup.
 (d) The exhaust pipe shall be deflected downward as it approaches the left side of the body.
(9) On a school vehicle, the system passes directly under the emergency door, there is a reduction in size of tail pipe after it leaves muffler, or system does not extend to outside, not more than 1/4 inch beyond the rear bumper as originally designed.
  (e) The exhaust pipe shall exit behind the driver's compartment. (10) Exhaust pipe, muffler, or tail pipe is not leak proof construction. Flexible pipe that does not leak is acceptable, except on school vehicles.
  (11) It emits continuous exhaust fumes or smoke which obscures persons or objects from view.
  (12) On a school vehicle, the system passes directly under the emergency door, or there is any reduction in size of the tail pipe after it leaves the muffler.
  (13) Type I school vehicle with left side exhaust does not meet the requirements established.