REPAIR ISSUE SYSTEM
The exhaust system gives in to corrosion faster than other car parts, although today more and more often pipes and silencers are made of aluminum-coated steel. However, there is nothing to be surprised: from the outside they bathe in brackish water-mud baths, and from the inside, in the products of combustion, including nitrogen oxides and water vapor, which form nitric acid when cooled. She impregnates soot deposits and is in no hurry to leave the maze of the silencer even through specially made openings (as, for example, on the Volga). Therefore, the exhaust system that has already worked has rusted intensively in the parking lot. The most difficult mode is short city trips, when the accumulated condensate does not have time to evaporate.
Shorten the life of pipes and mechanical loads - bending and twisting. Corrugated inserts have long been used on foreign cars so that engine vibrations do not break off a long “tail”, and individual parts of the system are often docked on movable ball joints. Of the domestic cars, only Svyatogor with an overseas engine can boast of corrugation, and the mobility of the ball joint on dozens is very arbitrary. On the “classic”, a very rusty exhaust pipe often breaks off along the clamp to the power unit. This happens on some old foreign cars (in particular, on the ancestors of the "Lada" - FIATs).
On domestic cars, the exhaust system usually lasts from two to four years, on foreign cars - up to six. The “trumpet voice" will announce a near demise. Places of gas leakage give out black traces of soot. You should not wait until the silencers fall out on the road, but before you go for parts, it is advisable to assess the damage.
If the reason is not in “cutting” gaskets, but in rusty holes, it is better to replace the affected part of the system. In domestic cars, it is desirable to have a muffler and a resonator at the same time (since they are relatively inexpensive), otherwise in a month or two you will have to climb under the car again. The front part (“pants”) is usually enough for two mufflers. If the pipes overlap (as in the Zhiguli), it is important that the gaps between them are minimal. It is better to check this before installing it on the car - in extreme cases, the defective part can be exchanged in the store. After pushing the pipes all the way, we mark their position with a risk, and we control the correct assembly on the car using it (otherwise, it is not easy to understand whether the pipe has fully entered).
In cars with a converter, the exhaust pipe, as a rule, made of stainless steel, is afraid of only mechanical damage. How to calculate a faulty converter and whether it is worth coughing up a new one, we already wrote (ЗР, 2000, No. 4, p. 180). It is not cheap - from 600 to 1200 dollars, and the rest of the system will cost a hundred or two for the “original”. Therefore, changing everything without looking back is not worth it - only a damaged element. Weld repair only makes sense if the pipe breaks due to load. A neat seam that does not tighten metal, relieving stress on the linings will delay the replacement for about a year. If the entire silencer is in rusty holes, welding will help at best for a month or two, a new outlet will erupt elsewhere. For sale - it will do, but it’s not profitable for yourself. Sometimes it is better to put a bandage made of asbestos tape with office glue, but remember: it only keeps on unloaded places. Some people weld domestic “pots” instead of the original resonator and silencer, but only a welder agrees to this, who has nowhere to go, and no money is needed: adjusting non-native parts in place is an art. And how much old pipes will last?
Is it worth it to shell out the “original” for a not-too-responsible site - the question is not idle. However, behind the brand mark is often something more substantial than just a name. So, a slight deviation in the orientation of the flange on the Bossal for the Honda Accord led to the car being struck by a hanging pipe along the speed bump. But without the original, the difference is almost impossible to notice. And the “Walker” for the same model turned out to have a resonator of a different shape (a “barrel” instead of a “cigar”) and a larger diameter - it also touches.
Together with silencers, we always change the gaskets. On many foreign cars, the factory has an integral exhaust system. When replacing individual elements, we cut it with a “grinder”, and connect the new parts with special clamps - either with flaring (as in “Samara”), or “pipe into pipe” (as in “Zhiguli”). In any case, when replacing it is not necessary to mess with the old joints - it is easier and faster to cut pipes with a “grinder”. Lubricate the new fasteners with a special high-temperature or graphite grease - the graphite remaining after burning it will help to remove the bolts (however, you can not save on them).
The suspension of the exhaust system is changed as necessary. When installing, make sure that the load on the gum is distributed approximately equally. At the Oka, this is almost impossible to achieve. To replace the left silencer suspension, it is necessary to support it with a jack or transmission rack (the right support is almost not loaded). However, an elastic band stretched like a string will still fly off soon, and the muffler will begin to beat on the bottom with each pulling. You can improve the situation by slightly extending the hook on the muffler (bringing it closer to the lower hook). On the “classic”, after installing the silencer mounting belts, we slightly bend their wire hooks with pliers to prevent them from flying off the fly. And instead of the M4 screw fastening the rear support, we will adapt a nail of a suitable diameter: slightly bent, it holds no worse than a regular screw, and it is installed and (which is especially important) it is removed much faster. To reduce the load on the exhaust pipe near the power unit, place asbestos cloth under the clamp, strip from the old cylinder head gasket, or simply apply high-temperature sealant. Some people generally remove the clamp, but in this case, the load on the mounting studs and the exhaust pipe gasket increases.
Finally, a few words about the emergency situation when the muffler fell apart on the way. The main thing is to raise the hanging end of the pipe so that it does not drag along the road, or completely remove the "excess" part. To restore the horizontal position of the fragment (with its entire suspension) will help the balancer - a long weighty stick (corner, pipe), firmly driven into the muffler at the back. It doesn’t matter if she touches the road - "by the wool" is not scary. More reliable "lay the tire" on a damaged muffler. It will serve as a small corner, a piece of reinforcement, in the extreme case, an instrumental screwdriver - we attract it to parts of the pipe with wire or worm clamps (Fig. 1). The corner can also be inserted into the pipe, and fixed from displacement with the same clamp (Fig. 2), or you can use a piece of thick steel wire (Fig. 3). True, it is advisable to go after this with low gas - so be quiet, and the mastic on the bottom (as well as the mains, gas tank, etc.) will suffer less from hot exhaust gases. Remember the danger of poisoning. However, sometimes it is possible to restore the system's performance by using a can of beer: to find it on our roads is not a problem. Cut it along, separate the lid and bottom (this can be done with a penknife). The resulting sheet of tin is applied to the damaged section of the pipe, we tighten the bandage with wire or clamps - and go!
Fig. 1. "Tire" for a muffler - fittings, corner or door. The tree is unsuitable - it can catch fire from hot gases.
Fig. 2. More reliable design: the inner and outer "tires" are pulled together with a clamp.
Fig. 3. The simplest way to fix the pipe is to firmly insert a loop of thick steel wire into it.