3.5. Diagnostics of a condition of the engine on appearance of spark plugs

1. A normal candle.

Brown or serovato-yellowish colour and small deterioration of electrodes. Exact conformity of thermal value of a candle for the engine and operating conditions.

GOOD ADVICE At replacement of candles on new establish candles with the same characteristics from among recommended by manufacturer.

2. Soot adjournment.

Adjournment of a dry soot specifies on rich топливовоздушную a mix or later ignition. Causes the ignition admissions, the complicated start-up of the engine and unstable work of the engine. Check up, whether the air filter is hammered, whether gauges of temperature of a cooling liquid and soaked up air are serviceable.

GOOD ADVICE Use "hotter" candle.

3. Oil adjournment.

Greasy electrodes and candle insulator. The reason — oil hit in the combustion chamber. Oil gets to the combustion chamber through directing valves or piston rings. Causes the complicated start-up, admissions in work of the cylinder and "twitching" of the working engine. Repair of a head of the block of cylinders and piston group of the engine is necessary. Replace spark plugs.

4. A metallic touch.

Adjournment on a skirt of an insulator of oxides of iron of brick-red colour from antidetonation ferriferous additives (ферроценов) to gasoline. Are postponed equal, a dense bed. At work of the engine with the big loading under the influence of a heat and pressure in the chamber of combustion oxides are restored in the current-carrying paths of pure iron closing the central electrode on "weight". It causes admissions of ignition and, as consequence, falling of capacity of the engine and the raised expense of fuel. Besides it can be damaged каталитический the neutralizer of the fulfilled gases strongly overheating at hit in it not burnt down in cylinders of the engine of gasoline. The touch practically cannot be removed mechanically, it does not burn out at long movement with a great speed. If the touch has appeared on new candles after small run, replace a refuelling place.

GOOD ADVICE If there is no possibility at once to replace candles new, try to remove this touch, having shipped candles for ten minutes skirts of insulators in ортофосфорную acid or the rust converter (contains ортофосфорную acid). After that clear a touch a nonmetallic brush (it is possible an old tooth-brush) and wash out candles at first water, and then gasoline.

5. The melted off electrodes.

Early ignition. The insulator white, but can be polluted because of admissions of a spark and adjournment getting on it from the combustion chamber. Can lead to engine damage. It is necessary to check up conformity of type of a spark plug, cleanliness of sprays of atomizers and the fuel filter, work of systems of cooling and greasing.

6. Ashy adjournment.

The Light brown adjournment covering with a crust the central and lateral electrodes. Are allocated from additives to oil or gasoline. Their big quantity can lead to isolation of electrodes of a candle that causes admissions in искрообразовании and faults at dispersal. If excessive adjournment are formed in a short space of time or at small run, replace маслосъемные caps of directing valves to prevent oil hit in the combustion chamber.

GOOD ADVICE If adjournment are stably formed at long run, the reason as gasoline — replace a refuelling place.

7. An insulator cracked or with сколами.

Detonation. It can lead to piston damage. Be convinced that октановое the gasoline number corresponds to the demanded.

8. Mechanical damages.

Damages can be caused the alien subjects which have got to the chamber of combustion, and in case of use of too long candle the piston can hook on its electrodes. It leads to candle destruction, switching-off of the cylinder and can damage the piston. Remove an alien subject from the cylinder and (or) replace a candle.