Two oxygen concentration sensors are installed on catalyst 5: diagnostic and main (control).
A metal-reinforced sealing gasket is installed between the cylinder head and the exhaust manifold flange, which is common with the intake pipe.
The inlet pipe of the additional muffler 1 is connected via a gasket 3 to the catalytic converter 5, and the outlet pipe of the muffler is connected to the flange of the main muffler 15 using a movable hinge. A toroidal metal-graphite ring 12 is installed between the flanges of the muffler pipes that form the hinge, and internal spherical surfaces are made in the flanges.
To reduce the transmission of vibration from the power unit to the exhaust system and body, a vibration-compensating corrugated bellows in a metal braid is mounted in the inlet pipe of the additional muffler.
Catalyst 5 is secured with nuts to the cylinder head studs and is additionally fixed to the engine with bracket 4 and clamp 6.
The exhaust system elements are suspended from the body on three identical rubber cushions 9 and one original cushion 14 for the rear mount of the main muffler.
To protect the engine and the body base from heating by the system elements, steel heat shields 2, 7 and 8 are installed in front of the catalytic converter 5 and above the additional muffler 1. In addition to them, an additional heat-insulating shield is installed in the engine compartment to protect the steering mechanism from overheating (not shown in the figure, as it is not damaged during operation and its removal during maintenance and repair of the vehicle is not required).
The exhaust system does not require any special maintenance. It is enough to periodically check the reliability of the tightening of the threaded connections and the integrity of the suspension cushions. In case of damage to the exhaust system components, through corrosion or burnout, they are replaced as a whole, since the mufflers together with the pipes are non-separable units.
Figure 4.10. Exhaust system: 1 - additional muffler; 2 - neutralizer thermal screen; 3 - gasket of the inlet pipe of the additional muffler; 4 - catalytic converter mounting bracket; 5 - exhaust manifold with neutralizer assembly (catalyst); 6 - clamp; 7 - front heat shield of additional muffler; 8 - rear heat shield of additional muffler; 9 - additional muffler suspension cushion; 10 - bolt; 11 - clamp; 12 - sealing ring; 13 - nut; 14 - main muffler suspension cushion; 15 - main muffler