Attention!
- All work on the exhaust system must be performed only on a cold engine, due to the risk of burns.
- The catalytic converter does not withstand impact loads.
The main criterion for replacing exhaust system components is their tightness upon completion of the replacement work.
The exhaust system weighs about 40 kg, so you should work with an assistant. Such elements of the exhaust system as the exhaust manifold, front (or intermediate) and back (additional) the mufflers are connected by detachable joints, so they can be replaced separately during repairs. Front muffler (1, see Fig. 3.30) connected to the exhaust pipes by a welded joint. It is necessary to check the tightness of the exhaust system especially in the case when starting the engine is difficult, the engine vibrates at idle, increases the rotation speed in jerks. This indicates a leak in the exhaust system between the exhaust manifold of the engine and the sensors (5, 6, see Fig. 3.29) oxygen content in the exhaust gases, which are installed before the catalytic converters.
The exhaust system should be checked on a cold or slightly warm engine in the following order. Start the engine and close the exhaust system outlet to the atmosphere with a rag (gag). Check for possible leaks through flange connections, by the noise of the exhaust outlet and by the formation of bubbles after spraying suspicious areas with a special fire-safe spray.
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