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» »How to use a vacuum cleaner to find a leak in the exhaust manifold of a car
The appearance of an exhaust gas odor in the passenger compartment is one of the signs that the exhaust manifold has leaked. It is rarely possible to find an obvious immediately noticeable crack on it, so usually it all comes down to the difficult search for a miniature hole when the engine is running. The collector heats up quickly, so you can burn your hands repeatedly, and find a hole. There is an alternative search method with a vacuum cleaner. It is fast, secure and very simple.

Required Materials


To diagnose the exhaust manifold you will need:
  • home vacuum cleaner;
  • piece of rubber hose;
  • funnel for liquid;
  • Scotch.

Leak search


It is necessary that the collector cools down, otherwise it is not safe to work. Having removed the nozzle from the vacuum cleaner, its hose should be connected to the exhaust pipe. It is unlikely that the diameters will coincide, so adhesive tape is useful here. It is advisable to remove air filters and a bag from the vacuum cleaner, if it is not of a container type, so that it does not absorb the smells of oil, fuel and burning from the exhaust system.
From a piece of rubber hose and funnel you need to build an impromptu stethoscope. If the diameter of the small hole of the funnel is less than the inner section of the hose, then everything can be compensated with tape.
How to use a vacuum cleaner to find a leak in the exhaust manifold of a car

Turning on the vacuum cleaner, you need to go to the muffled cooled engine and applying a stethoscope to the collector to listen to where the air is drawn in. It is necessary to rearrange the end of the hose smoothly without gaps.
How to use a vacuum cleaner to find a leak in the exhaust manifold of a car

After detecting a possible hole, you need to close it with your finger, if the noise stops, then the smoke just goes out through it. Most likely there will be more than one hole. In order not to lose finds, they should be marked with chalk.
How to use a vacuum cleaner to find a leak in the exhaust manifold of a car

After detecting all the holes, the collector can be removed and brewed, sealed or coated with sealant, in general, as you like. Of course, they haven’t come up with anything more reliable than welding.
This method is very good, but even better if the vacuum cleaner has a blow function. When operating in this mode, it will not suck in bad air from the exhaust system, so there is no need to remove the filters. When blowing out of the openings on the manifold, air will come out, not be sucked in.
Using a vacuum cleaner, you can look for holes in the muffler and in the exhaust system as a whole. In this case, you do not need to burn your hands and rush, therefore, upon completion of the diagnosis, it is quite possible to find all the holes at one time and carry out a complete repair.
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Comments (1)
  1. Guest Alex
    #1 Guest Alex Guests January 24, 2019 9:34 p.m.
    2
    the author forgot that air will pass through the valves into the cylinders without hindrance (there is a phase when all the valves in the cylinder are open) and then into the inlet tract and out into the atmosphere, so you hear hissing there. To complete the experiment, you need to remove the air filter and plug the inlet with something like a tennis ball or something else, depending on the diameter of the inlet pipe

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