OVERHAULING OF HORN

-



Aim:

OVERHAULING OFHORN & TUNING

TOOLS REQUIRED:

1. SCREW DRIVER (-,x)
2. FEELER GAUGE
3. MULTY METER
4. 10mm D/E OPEN SPANNER

MATERIALS REQUIRED

1. EMERY PAPER
2. COTTON WASTE
3. GREASE

PROCEDURE

Dismantling 

Disconnect the wires from the horn assembly and remove the mounting nuts and take out the horn unit

Remove the horn from the vehicle.

Loosen the cover fixing screws.

Remove the cover, packing washer, diaphragm assembly  and shim.

Remove the terminal's nuts and washer.

Remove the contact breaker assembly from the housing.

Inspection

Clean the contact breaker points with fine emery paper. If necessary, replace the points.

Check the coil for continuity and resistance by an ohmmeter for 12 volt - 0.75 -0.85 ohm and for 24 volt - 3.25 -3.5 ohms.

Replace the coil if found burnt or defective.

Check the diaphragm visually, replace if it is found damaged.

Check all the screw threads visually, and if necessary, replace the screws. Clean all the parts.

Assembling

Place the contact breaker assembly in its position. Fix the terminal, washer and nuts. Fit the shim, diaphragm, packing washer and
cover .

Turn the adjustment screw so that the contacts remain closed, when the armature is attracted to the core. Mornentarily energise the coil winding by a low voltage supply.

Measure the armature  air gap with the help of a dial gauge.

Note: The correct air gap settings are for low voltage - 0.020"/0.025" for high voltage - 0.016/0.022".

- Refitting horn to the vehicle and test

Tuning of horn

Check the tonal quality of the horn while blowing. If the tonal quality is not satisfactory, check the voltage at the horn terminals with the horn kept blowing.

The voltage should be 11 to 14V for a 12V horn and 22V to 28V for a 24V horn. Simultaneously check the current, (if necessary) drawn by the horn.

Turn the adjustment screw using a proper tool and check for its performance. Repeat the adjustment until a satisfactory performance is achieved.

In a twin-horn, do the tuning procedure first for one horn by disconnecting the other and vice versa.

Place the horn in its place, tighten the mounting bolts and nuts.

Connect the wires.

Check the horn button connection.

Press the horn button to ensure that the horn performs satisfactorily and the horn note is correct.

RESULT:

THE OVERHAULING OF ELECTRIC HONE IS DONE SUCCESSFULLY.

Popular posts from this blog

MAJOR PARTS OF AN IC ENGINE

-
Image
ENGINE COMPONENTS 1. CYLINDER BLOCK      The cylinder block is the main body of the engine. Cylinder head is mounted on the cylinder block. It houses iniet and exhaus valves. Crank case is attached to the bottom of the cylinder block. Crank case supports the crank shaft. Oil pan is attached to the bottom of the crank case. Cylinder block contains large cylindrical holes called cylinder bore. The cylinders are accurately finished to accommodate pistons. The space above the piston inside the cylinder at TDC called the combustion chamber. Combustion of fuel inside this space, high pressure and temperature will be developed inside the cylinder. Therefore, it should be made of material which can resist high pressure and temperature (2800°C). In water jackets has around the cylinders for the circulation cooling water to absorb the temperature while running of an engine. 2. CYLINDER HEAD Cylinder head is a separate casting placed on top of the cylinder block by studs and nuts. It houses the i
Read more

INTRODUCTION TO ENGINE ( for NCVT)

-
Image
Engine : It acts as the power unit. The internal combustion engine is the most commonly used in automobiles. It is of two types ; (i) Spark ignition (ii) Compression ignition.         Both engines are called heat engines. A steam engine is an external combustion engine because the fuel is burned outside the engine. The principle of working of an external combustion engine is shown in the figure below. COMPARISON BETWEEN INTERNAL AND EXTERNAL COMBUSTION ENGINES      The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber. In an internal combustion engine the expansion of the high temperature and pressure gases, which are produced by the combustion, directly applies force to a movable component of the engine, such as the pistons and by moving it over a distance, generate useful mechanical energy.          The internal combustion engine is quite different from external combustion engines, such
Read more

HEAD LIGHT CIRCUIT WITH 6 LEG RELAY

-
Image
  AIM : Head light circuit TOOLS & MATERIALS REQUIRED : 1. Wire striper 2. Combination plier 3. Screw driver (+,-) 4. Wire(required) 5. Head light switch 6. Dipper switch 7. Relay - 6 leg 8. Insulation tape 9. Battery 12v 10. Head lamp 12v Diagram PROCEDURE 1. ബാറ്ററിയുടെ +ve ടെർമിനലിൽ നിന്നും fuse വഴി relay യിലേക്കും head light സ്വിച്ചിലേക്കും red wire ഉപയോഗിച്ച് connect ചെയ്യുക. 2. Head light സ്വിച്ചിൽ നിന്നും dipper സ്വിച്ചിന്റെ center point ലേക്ക് red wire ഉപയോഗിച്ച് connect ചെയ്യുക. 3. Relay യുടെ dim, bright connection യഥാക്രമം dipper switch ന്റെ Low, High ബിം പോയിന്റിലേക് connect ചെയ്യുക. 4. അതിനുശേഷം Head light ൽ നിന്നുള്ള loop ചെയ്ത High beam Low beam വയറുകൾ relay യുടെ high, low beam വയറിലേക് ബന്ധിപ്പിക്കുക. 5. Relay യിൽ നിന്നുള്ള -ve ഉം, head light ൽ നിന്നുള്ള -ve ഉം യോചിപ്പിച്ചു battery യുടെ -ve ടെർമിനലിലേക് connect ചെയ്യുക. RESULT HEAD LIGHT CIRCUIT വിജയകരമായി പൂർത്തീകരിച്ചു.
Read more