The fuel filter (or stainer) prevents the fuel pump and injectors from developing troubles and clogging by removing contaminations such as dust and steel particles as well as water in the fuel, to maintain the engine in an optimum operating condition. it also prevent abrasion insida cylinders,particularly in the upper sections.
The petrol in the fuel tank can contain a considerable amount of dirt and water which ,if passed through the carburetor and injectors,will clog and cause the engine to malfunction.
In diesel engines, too,dirt or moist can get mixed into the diesel fuel.If this dirt or moisture passes through to the injection pump or injection nozzles,it could cause clogging ,wear or seizure of precision part.
The fuel filter separates the contaminations from the fuel and prevents the above-mentioned problems.
However,if contaminations accumulate in the fuel filter,it becomes clogged and limits the fuel supply amount.
Maintenance
For petrol engine replace every 40,000km/24 months whichever comers first.
For diesel engine check filter and drain water every 10,000km/6 months and replace every 40,000km /2 months ,whichever comes first.
Replacement interval must be shortened in the area where proper quality fuel is not always available.
Under severe condition like dusty condition or weather conditions are extremely severe ,replace every 20,000km/12 months,whichever comes first.
Friday, June 20, 2008
FUEL FILTER
Sunday, June 1, 2008
IGNITION SYSTEM
FUNCTION
Spark plug transmits an extremely high voltage across the electrodes to produce sparks, which ignite and explode the air-fuel mixture compressed in cylinders of a petrol engine.
Necessity of maintenance / What happens if not done
With use ,the spark plug electrodes experiance a gradual erotion and widening of the gap between them, making spark generation difficult. At the same time , combution deposits on the insulator tip and the electrodes cause short circuit of the current, resulting in sparks between impropper portions.
If the plugs are worn, the engine performance will decrease and fuel economy will become worse.
If the ignition timing is advanceed too much , or retarded too much,it will cause the engine's power decrease.
Maintenance Interval
Spark plug ( conventional type )
- Inspect and correct or replace as necessary every 10,000km /6 months and replace every 20,000km /12 months ,whichever comes first.(When using leaded petrol , it is recomendable to replace spark plug earlier( to a half or a third) than the one using unleaded petrol.)
Spark plug ( Platinum- tipped type )
- Replace every 100,000 km
Ignition wires
- Inspect and correct or replace as necessary every 40,000km / 24 months, whichever comes first.
Ignition timing
- For emission-controlled engine , adjust the timing every 20,000km / 24 months, whichever comes first.
- For non emission-controlled engine , adjust the timing every 10,000km / 6 months, whichever comes first.
- In the case of some latest engine , ignition timing adjustmentis not necessary.
Maintenance job
- Clean the plug with wire brush and check for damage or cracks ( for platinum type or Iridium type do not clean )
- Check plug gap with plug gap gauge (Only conventional type )
- Inspect wire for cracks, damage,burned terminals and for improper fit.
- Measure the resistance of wires and check for intermitent breaks.
- Check ignition timing and adjust as necessary.
TIMING BELT
FUNCTION
Timing belts transmit drive power to the camshaft(s) from the rotating crankshaft thus enabling the intake and exhaust to open and close in accordance with the valve timing pattern specified for each type of engine.
Necessity of maintenance /What happen if not done
The timing belt gradually becomes worn, hard or slack as it is used ,and it will finally jump over the sprocket teeth, and in the worst case , break.
If timing belt jumps over the sprocket teeth;
- Engine power will decrease
- Fuel consumption becomes worse
If belt tension becomes too low;
- Belt vibration noise will be notified
If timing belt breaks;
- Intake /exhaust valves and pistons will crash with each other and will be damaged
Maintenance Interval
Replace every 100,000km or sooner, depending on usage conditions.(There is no need of replacements for timing chains, which are basically maintenance free)
AIR CLEANER FILTER
FUNCTION
The air taken in by engine contains dust and other particles. The air filter traps dust and dirty particles in the air with its filter, preventing them from entering the cylinders.
There two types of air filter element
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- This type used oil-permeated filter paper. As the paper sticky, dust and other particles in the air adhere to the paper as air passes through it. This type has much bigger filtering capacity than dry paper type filter of the same size.
- This type is appropriate for the desert area.
Necessity of Maintenance/ What happen if not done
The filter becomes clogged with dirty and the air flow will be restricted.
If dust or other particle enter the cylinder or the air floe is restricted due to the clog;
- Engine cylinder will wear rapidly.
- Fuel economy will become worse because of improper combustion of air-fuel mixute.
- Engine performance will become worse ( poor engine power or poor acceleration ,etc.)
- Exhaust gas emission becomes worse.
- Black smoke will increase (diesel engine)
Maintenance Interval
Replace every 40,000km /24 months ,whicever comes first.
For dry paper typr, clen every 10,000 /6 months ,whichever comes first.
Driving under dusty conditions, they should be replaced(viscous type) or cleaned ( dry type) more frequently.
ENGINE OIL FILTER
FUNCTION / MECHANISM
The oil filter removes harmful contaminations from the engine oil which lubricated areas of engine interior subjected to friction.
The oil filter has a drain-back prevention valve to inhibit the oil in the filter and oilpassage to flow back to oil pan when the engine is tuned off. This function is to supply oil to all the friction surfaces inside the engine as soon as it is started;and thus, prevents wear which otherwise would be caused by lack of the oil film at metal to metal contack portions.
Necessity of Maintenance / What happens if not done
Engine oil will become dirty due to the carbon , metal particels or dust etc. Such contaminations accumulated in the filter , the filte's filtration capacity will drop.
If dirty engine oil filter is continuosly used;
- Engine oil will quickly become dirty.
- Engine will be damaged because of contaminated oil.
Maintenance Interval
Replace every 10,000km /6 months, whichever comes first. It is desirable that the oil filter is changed every time the oil is changed because about 0.5liters of used oil would remain in the filter if it werw not replaced. This would accelerate deterioration of the new oil.
