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Diagnosis of failures when starting the engine on the road

Check ignition systems and electrical equipment

PERFORMANCE ORDER

Turn on the ignition and check of serviceability of the emission warning lamp on the instrument panel. Include a starter and check the stability of the engine cranking them. Turn on the headlights and check the intensity of their glow. If the headlights are off, and the starter does not turn the engine, proceed as follows: Disconnect the battery and strip both terminals and terminal clamps (see. Accompanying illustration). Reconnect the wires and reliable (but not excessively) tighten the clamps. When poor contact terminals are usually noticeably heated after several start attempts. Check the condition and mounting of tires on the ground battery engine, the engine on the frame. Also check the tire contacts for signs of oxidation and contamination. Check the wires from the battery to the starter, and the structural condition of the traction relay of a starter. Also check the cleanliness and loose terminals wire. Repeat testing of the first three paragraphs of sub-section. If the starter motor still does not turn the motor or lamp is not lit, it is possible one of the following situations.

Do not operate the starter motor or lamp

• Faulty or discharged battery.

Lights off, but the starter does not work

• Out of order fuse on the battery.

Drive starter stuck being introduced into engagement with the flywheel

• Faulty magnetic switch starter.
• Faulty ignition switch.
• On models with AT - faulty circuit breaker tripping starter, fuse or relay.

Lights are lit with low intensity, and the starter is rotating too slow

• The battery is low or faulty starter motor.
• The battery is exhausted due to breakage or slippage of the drive belt of the generator. The bursting of one or more cells in the pack.

Models with contact breaker

PERFORMANCE ORDER

Set the electrode gap of the spark plug replacement served type equal to 6 mm. Securely ground the candle using the jumper wire (see. Accompanying illustration), or tightly clutching a candle to a properly grounded point on the engine block (primotat its cord or tape). Remove the spark plug wire and connect it to the test candle. Ask the assistant to include a starter. Between the electrodes of the spark test spark should slip. If there is no spark, or it has a yellow color and low intensity, go to the procedure of the next paragraph. If the spark has enough intensity, skip the following checks. Disconnect the ignition coil from the distributor cap and move it to the test candle. Repeat the above test. If a candle is formed a strong spark of a bright blue color, the reason for the refusal lies in the failure of the distributor cap, his slider, the screen switching rev limiter or the spark plug wires. If the spark is still missing, switch off the ignition and check the following: Check the condition of explosives candle wires (see. Accompanying illustration), - they must be clean, dry and free of cracks in the insulation. Check for moisture and dirt distributor cap. Inspect the inner surface of the cover and the screen rev limiter distributor for cracks and coal paths (see. Accompanying illustration), paying particular attention to areas between the contact segments of the spark plugs in the lid and the electrodes in the screen. Check Rotor, distributor for cracks, dirt deposits and burnouts metal spout. Verify the presence of place and serviceability limit spring rotation slider button (on an accompanying illustration shows a test of the spring slider model 4.2 l). Check the cleanliness, dryness and is mounted in the lid of the distributor contact connections Siches wires and ignition coils. Make sure that the carbon brush in the center of the inner surface of the distributor cap is clean and dry. Check the condition and mounting HB wires on the ignition coil. Make sure there are no signs of oxidation of the terminals. Make sure that the electrical current reaches the coil when the ignition. Use a lamp-sampler, including HB between its positive terminal of the coil and a good ground point (see. Accompanying illustration). Make sure that the breaker contacts are open, or to insulate them at the time of this test dielectric tape. If the lamp lights, the probe being connected to the reverse side of the ignition switch and the coil does not burn when connected to a circuit breaker contacts facing side, there is a possibility of damage of the primary winding of the coil. Remove the spool and check it by substituting a known good. Check the condition of contacts of the breaker, if necessary, clean them and adjust. Check the condition and fastening of the ground wires of the distributor. Repeat the test. If the spark is still absent, or there is a slight spark of yellow, there is a possibility of one of the following failures.

The lamp is not lit

There is an open circuit between the ignition switch and the positive terminal of the coil. Again, using the lamp, make sure the probe in good supply power to the ignition and HB engine wiring harness connector.

If the lamp-sampler is not available, HB wire can be removed from the ignition switch turned to the part of the coil and lead to a properly grounded point to check the current availability. Similarly, the second conductive HB can be disconnected from the distributor and grounded to check the current. In the course of checking the item g) seeing to it that the breaker was open (insulated), and the ignition is switched on (key - in position ON).

Defective coil, a capacitor, or spark plug wires

On the refusal of the strong points of the coil burnout or breaker contacts or having them deep cavities - replace the condenser and breaker points.

If during the execution of the above checks and correction of identified defects is possible to achieve sufficient efficiency spark, but the engine still does not start, remove all the spark plugs and check their condition and value of inter-electrode gap.

Models with electronic ignition

PERFORMANCE ORDER

Set the electrode gap of the spark plug replacement served type equal to 6 mm. Securely ground the candle using the jumper wire, tightly clutching a candle or a properly grounded point on the engine block (primotat its cord or tape). Remove the spark plug wire and connect it to the test candle. Working with an electronic ignition system or in the vicinity of its components should observe certain precautions related to the dangers of electric shock upon contact with the explosive elements of the primary and secondary circuits of the system. Before proceeding to connecting or disconnecting any components of the electronic system, turn off the ignition to avoid the risk of electric shock and failure of the ignition system. Ask the assistant to include a starter. Between the electrodes of the spark test spark should slip. If there is no spark, or it has a yellow color and low intensity, go to the procedure of the next paragraph. If the spark has enough intensity, skip the verification described below. Disconnect the ignition coil from the distributor cap and move it to the test candle. Repeat the above test. If a candle is formed a strong spark of a bright blue color, the reason for the refusal lies in the failure of the distributor cap, his slider, the screen rev limiter or the spark plug wires. If the spark is still missing, switch off the ignition and check the following: Check the condition of explosives candle wires - they should be dry and free of cracks in the insulation. Check for moisture and dirt distributor cap. Inspect the inner surface of the cover and the screen rev limiter distributor for cracks and coal paths (see. Accompanying illustration), paying particular attention to areas between the contact segments of the spark plugs in the lid and the electrodes in the screen rev limiter. Check Rotor, distributor for cracks, dirt deposits and burnouts metal spout. Verify the presence of place and serviceability limit spring rotation slider button (on an accompanying illustration shows a test of the spring rotor model 4.2 l). Check the cleanliness, dryness and is mounted in the lid of the distributor contact connections Siches wires and ignition coils. Make sure that the carbon brush in the center of the inner surface of the distributor cap is clean and dry. One should not make further checks the electronic ignition system, as their implementation is associated with the risk of electrical shock due to the high voltage present in the primary and secondary circuits of the system. Terms of the procedures described in the section on electronic ignition system. If during the execution of the above checks and correction of identified defects is possible to achieve sufficient efficiency spark, but the engine still does not start, remove all the spark plugs and check their condition and value of inter-electrode gap.

Check the power supply system

Provided guarantee the availability of fuel in the tank of the first test should be to check the presence of fuel in the float chamber of the carburetor. On carburetors equipped with a viewing window, check the presence of fuel in the chamber visually. The fuel level should reach the middle of the viewing window.

To perform the following test, you remove the air cleaner assembly and check out the carburetor throat when the air flap is open. Continuing to look into the throat several times, open and close the throttle, moving her hand thrust. When moving the throttle fuel injection occurs through the discharge nozzle accelerator pump, which means that the float chamber is filled with the power and the system is functioning properly (see. Accompanying illustration).

If the injection does not occur, proceed as described below.

PERFORMANCE ORDER

Disconnect the ignition coil connector HB avoid accidental starting of the engine during testing. Disconnect the fuel hose from the carburettor and lower it into the drain capacity. Ask the assistant to include a starter a few times and watch the expulsion of fuel from a hose. If fuel spills into the container properly, skip described in the following three paragraphs procedure - if not, go through the process. Disconnect and remove the hoses from the engine compartment fuel filter. Make sure that the filter is blown in both directions. If necessary, make its replacement. Install the defective filter into place, securing the hose clamps securely. On l models 4.2 disconnect the fuel supply line from the fuel tank from the inlet side of the fuel pump. Remove the filler cap of the fuel tank and ask the assistant to listen to the sound coming from the throat. Blow into the fuel line toward the fuel tank. If the permeability of the line is not broken, Assistant hear gurgling in the tank. The above test can not be performed on a 3.0 liter models, since they are equipped with a built-in tank electric fuel pump equipped with a one-way check valve. If after cleaning the fuel filter the fuel supply is not restored, call for more information to the section dedicated to the power supply system and follow the appropriate verification of serviceability of functioning of the electric fuel pump. Connect the fuel line to the fuel pump and check the flow of fuel from the pump. If the supply of fuel to the carburetor side of the pump is not, it is possible one of the following failures.

L models 3.0

• Faulty fuel pump.
• Knocked fuse.
• Defective wiring.
• Faulty control unit.
• Broken permeability fuel lines.

Models 4.2 l

• Gurgling in the tank by blowing a gasoline can not be heard
• Broken permeability fuel line or there is a break.
• Clogged strainer fence line fuel.

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PERFORMANCE ORDER

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PERFORMANCE ORDER

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The following procedure shall be fulfilled if the normal starter cranking engine. Otherwise, squeeze the clutch to disconnect the engine from the gearbox (models with Manual transmission).

If the starter motor still can not turn the engine, then the cause of failure is not the fault of transmission, - remove the starter and try to crank the engine by hand. This verification will determine whether the cause of the failure lies in jamming or failure of the starter, or there is a mechanical failure of internal engine components such as connecting rod and piston assembly, crankshaft, etc. If the starter motor in order and can not be turned by hand, refer to the section dedicated to the diagnosis of the causes of mechanical failure of the engine below.

It should be remembered that the only correct way to test the compression pressure in the cylinders of the engine is to test using a compression tester. Described below method of checking the compression ratio allows only a rough estimate the general shape of the mechanical condition of the engine.

PERFORMANCE ORDER

Remove the radiator cap and check the coolant level in it. If the level is too fell, carefully inspect the power unit for signs of external leaks. Remove the dipstick motor oil, and check the blade for signs of foaming oil (see. Accompanying illustration). If the oil is at the cutting edge of the probe has a milky consistency, while increasing its level, pass the following three operations and proceed to further checks. Disconnect the ignition system by disconnecting the positive wire from the ignition coil. Remove all spark plugs, except for one. Include a starter and listen to the sounds made by crank the engine. Alternately rearrange candle in different cylinders, then recheck. The sound is produced when a cylinder with low compression will vary significantly by ear. Furthermore, defective cylinder will produce a noticeable resistance to turning of the engine, while cranking installed into the cylinder with reduced compression candle will occur freely. If in the course of these checks will be revealed leakage of the coolant, and the presence of traces of it in the motor oil or spark plugs, check the condition of the cylinder head gasket, inspect the unit and cracks, as well as to measure the flatness of the mating surfaces of the head to the block. If, during the evaluation test the degree of attenuation of the compression found or uneven distribution of the compression pressure to the list mentioned in the previous paragraph should be added to the possible causes of the defect of the piston (s) and the burn-out or defective valve (s). If in the course of these audits did not reveal signs of internal coolant leaks, continue the diagnostic procedure by performing test described below. Remove the cover from the distributor of ignition and make sure that when the starter slider distributor rotates synchronously with the engine. Remove the cylinder head cover and the starter valve is properly opened and closed during engine cranking. Further, if the slider or the flap is not functioning properly, the following options are possible.

Rotor does not rotate, but the valve works properly

• Cut the distributor drive gear or shaft.

Do not operate either the slider or flaps

• There is a defect, or a camshaft timing belt (3.0 liters) / circuit (4.2 liters).

If in the course of the proper implementation of all the above checks no abnormalities were detected, we can only verify the installation of the ignition timing and valve timing. It should be noted, however, that if the cause of failure is a violation of the ignition timing is necessary to find out the cause of this disorder, especially if until recently the engine is started and functioning properly.

To check the ignition timing and valve timing is necessary to remove the distributor cap and the cylinder head and crank the engine in a clockwise direction for the crankshaft pulley so that the piston of the first cylinder in the position TDC. At the same time the valves of the first cylinder shall be closed and the slider to turn the distributor spout to the segment BB spark plug wire of the first cylinder in the distributor cap.