What is the role of a filter?

To separate out and prevent potentially contaminant particles from entering the engine. Air and fuel - dust particles, sludge and carbon.

What is filter efficiency?

The percentage of dirt that a filter removes. The filter paper or 'media' determines what the oil, air or fuel has to pass through and where the dirt is trapped. The more twists and turns a particle of dirt has to take, the more likely it is to be captured.

The higher the efficiency, the higher the % of dirt retained by the filter. Filters are least efficient when new and become most efficient just before "plugging".

What is filter media?

Media is a mixture of various fibres bonded together.

The 'media' paper filters out the contaminants passing through the oil, air or fuel filter. Quality and quantity of media are very important. Some media may look similar but can perform differently. The function of filter media is to remove the greatest amount of contaminants while offering the least resistance to flow.

Does more pleated media filter paper mean better filtration?

Generally a filter with more media has the ability to trap more contaminants than one with less. Few pleats means little media and low capacity. Irrespective, the media must contain the appropriate resins and compounds.

What is filter life?

How long a filter lasts before clogging up. Dust-holding capacity of the filter determines how long its life is. The more high-quality paper inside the filter the more dirt it will hold and the longer it will last.

What is flow?

How easily air, oil or fuel flows through the filter. Minimising resistance to flow ensures that the engine is never starved of air, oil or fuel. Poor flow in a filter deprives engines of their vital needs, causing them to work harder, lose power and create rapid engine wear over shorter periods.

Is a regular service interval filter change necessary?

Given the importance of efficiency, life and flow, regular filter changes with a good quality filter provide optimum performance and engine life.

What is a micron?

A micron a measurement equalling one millionth of a metre.

What is micron rating?

A measure of the pore size in the filter media. Expressed as either 'Nominal' or 'Absolute'. Nominal Rating relates to the percentage of particles at a given size that a filter can capture ie. 10 microns at 90% means it will remove 90% of particles 10 microns in size. Absolute refers to the removal of all particles at a given micron size and larger i.e. 20 micron absolute means 100% of particles 20 microns or greater will be captured.

The lower the micron rating, the greater the efficiency and hence the amount of dirt that is captured.

Common oil filter micron rating is approximately 30

What is an anti drain back valve?

It stops oil from draining out of filter and oil galleries when the engine is shut down and aids quick flow of oil to engine on start up. Not all filters require anti drain back valve due to the construction of the engine.

What is the by-pass valve?

Should the oil filter become blocked, the valve will open allowing oil to flow into the engine. (Unfiltered oil is better than no oil).

What is the difference between a full flow and a bypass oil filter?

Full flow is where 100% of the oil passing through the same media before entering the engine. Bypass filters are more restrictive and take a portion of the oil and filter out smaller particles that can or have passed through the full flow filter.

What is over pressurisation?

When the oil pressure valve temporarily sticks, it subjects the entire lubricating system to extreme pressures. Under these conditions the oil filter generally expands as the increased pressure tries to force the filter off the engine. Ryco filters are built to withstand 3 times normal operating pressure. Refer to Ryco Catalogue for further details.

What is the difference between fuel filters used on carbureted systems versus EFI?

Generally the carburetted system operates at low pressure and has relatively low flow. Filters are often nylon bodied.

EFI filters are metal bodied, and designed to handle higher pressures and flow. The media can also differ between filter types.

When should I change my air filter?

The air filter should be changed in relation to operating environment of vehicle, eg in hot, dusty conditions more regular frequent change period is required. In any case recommend change every 12 months irrespective of conditions or distance travelled.

A blocked air filter can significantly increase fuel consumption. In addition, it can increase cylinder bore wear due to excessively high fuel to air ratios.

If I fit a good quality filter, can I use low quality oil?

A quality filter will not save your engine from excessive wear if there is prolonged use of a poor quality oil. Low quality oil generally means the oil additives deteriorate quicker, putting more stress on the engine.