10-12-7-diagnostika-shuma-skripa-i-drebezzhaniya.html
10.12.7. Diagnostics of noise, a scratch and jingleThe assistant should operate the car while the technician reveals a place where there is a noise.
At carrying out of tests, precisely define a place of occurrence of noise. Often there are external and internal noise. At the termination of the repair, any malfunctions, check up occurrence of noise and eliminate them. At carrying out of test, definition and noise elimination use:
- A stethoscope or a vacuum hose;
- A sticky tape;
- A sealant;
- An indelible pencil;
- A screw-driver.
For carrying out of road tests:
- Define a technological route which includes smooth and direct sites of road. The movement direction gets out in all four - directions (the north, the south, the east and the West);
- Choose a direction with small traffic or extraneous noise which would interfere with a course of tests;
- Operate the car with a speed at which it is possible to reveal noise or while noise will not appear. Do not exceed regulated - restrictions of speed.
External noise can appear:
- At movement against a wind;
- Behind glasses of doors and when the car begins movement.
Noise can be eliminated the sticky tape pasted on various ledges and bends of a body.
Internal noise — air vortical leak of the car.
To reveal leak, stick with a sticky tape of connection of a rack of a body with glass to close possible cracks. It will cause growth of pressure of air and noise in the car will amplify;
Use a stethoscope or a vacuum hose to reveal a noise place.
Temporarily eliminate noise by a sticky tape and continue check to define, whether noise is eliminated or there are other cracks.
When all cracks are found, make repair work with appropriate carefulness.
Diagnostics of noise, scratch and jingle, their possible reasons of display and elimination methods are resulted in tab. 10.4.
Table 10.4 Diagnostics of noise, a scratch and jingle, their possible reasons of display and elimination methods
Plausible reason
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Elimination method
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The scratch which is starting with the lateral directing
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The inadequate image fixes a brake highway
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Fix tubes of brake system a sticky tape and hear, whether there is a scratch.
Establish plastic tapes to guarantee rigid communication of brake tubes
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Scratch under the car at high frequency of rotation of a cranked shaft
|
The thermofilter touches the body bottom
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Lift the car and visually examine it.
Bend slightly a thermofilter to avoid contact to the body bottom
|
Scratch from a forward part of the car in cold weather
|
Stabilizer plugs have lost the properties
|
On not heated-up car spend test arrival on rough road and examine a forward suspension bracket.
Remove stabilizer plugs, wind with a sticky tape the stabilizer. Establish plugs of the stabilizer over a sticky tape
|
Knock from a back part of the car
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The inadequate image fixes a spare wheel in a luggage carrier compartment
|
Open a door of a luggage carrier and examine fastenings of a spare wheel and the tool.
More strongly tighten fastening of a spare wheel and the tool.
Conduct road test; whether check up knock has disappeared
|
Jingle of glass from a back part of the car at engine start-up
|
The lock of a door of a luggage carrier is not adjusted
|
Conduct test tests of the car; check up jingle presence.
Ослабьте nuts of fastening of the lock also move the lock more low
|
Knock in the doorway
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Ослаб the cylinder of the lock of a door
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Remove an upholstery of a door and check up fastening of the cylinder of the lock.
Tighten bolts of fastening of the cylinder of the lock
|
Jingle of electric sockets under a door upholstery
|
Remove an upholstery of a door and establish a knock source.
Remove an upholstery of a door and fix electric sockets properly
|
Scratch at opening of doors
|
There is not enough greasing in pins of loops
|
Open a door and establish a scratch source.
Wipe pins of loops kerosene and put lubricant
|
The terminator of opening of a door is insufficiently greased
|
Open a door and establish a scratch source.
Wipe the terminator of opening of a door kerosene and put lubricant
|
Scratch from under the console at a gear change (in cold weather at the cold engine)
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Malfunction in a protective cover of the lever of a gear change
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Switch the lever of a gear change and establish a scratch source.
Remove the console, replace a protective cover or add talc
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Scratch from under facing of the panel of devices
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Friction of facing of the panel of devices about the control panel
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Conduct road test of the car and be convinced available a scratch.
Remove facing of the panel of devices and establish on edges a felt tape
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