Caution! Checking and repairing exhaust system components should only be performed after the system has completely cooled down.
1. The exhaust system consists of an exhaust manifold, catalytic converter, muffler, exhaust pipe and the pipes, brackets, hangers and clamps connecting these elements. The exhaust system is attached to the body from below with various brackets and hangers (see Figure 17.1).
Figure 17.1. The exhaust pipe and catalytic converter are attached to the underbody of the vehicle using rubber mounts (shown by arrows).
If any part of the system is damaged or installed incorrectly, it will transmit extraneous noise and vibration to the body.
2. To keep the system in good working order and safe, regular checks should be carried out (see Figure 17.2).
Figure 17.2. Check the rubber mounts of the exhaust system (shown by arrows) for the absence of cracks.
During inspection, check for damaged or bent components, broken welds, burnt holes, excessive corrosion, or other defects that could cause exhaust gases to enter the passenger compartment. Rusty system components are usually replaced with new ones; "Welding" rusty mufflers helps only for a short time.
3. To remove rusty components of the exhaust system in order to replace them with new ones, mechanical, pneumatic and electric cutting tools are used. If you want to save money on hiring a mechanic but don't have a cutting torch, you can cut the muffler with a regular hacksaw. If you decide to do this yourself, wear safety glasses and gloves.
4. Below are some recommendations for repairing the exhaust system:
When removing components, start with the exhaust pipe, "from tail to head".
If the nuts and bolts are wetted with a "liquid key" before unscrewing (see Figure 17.4), things will go faster.
Figure 17.4. Before you begin to loosen the bolts and nuts securing the exhaust system components, lubricate them with penetrating lubricant.
When installing new components, always use new gaskets and fasteners.
Before installation, lubricate the threaded elements with a non-stick compound. Before final tightening of the clamps, ensure that there is sufficient clearance between the exhaust system components and the body, and that the hot catalytic converter will not melt the carpets and plastic in the cabin - install the heat shields in their places.
Caution! When the engine is running, the catalytic converter reaches high temperatures and takes a very long time to cool down. Wait until the catalytic converter has cooled completely before removing it.