The main function for oil filter is to impurity the oil and provide clean oil lubrication to engine components to reduce the friction loss and improve engine efficiency.

1)  As oil filter is a vulunerable part, customers need to replace the oil filter together when changing the oil every time.  And it plays an important role in car maintenance. Because of this properties, it is important to know how to distinguish the oil filter is good or bad.

2)  Poor qualiy oil filter will have bad effect on the lubrication of the engine. Because some oil filter are in bad quality and it is not connect well bettween the main oil-road, which cause oil jumped out on the bonding surfaceod the cylinder. Under these bad conditions, it leads to the engines not wor efficiency,some even will belew. Therefore, we must choose carefully when selecting the oil filter.

Good quality of oil filter

1). Filter painting and filter printing is good

2). It has a bypass-valve to ensure oil supply normally

3), Inhibiting reflux designed to ensure that there is a certain amount of the oil filter in the oil, reducing wear during cold start.

4). before delivering the oil filter,  Fitted with a protective bag, interface lubricating grease, and sealing gasket material.

Poor quality of oil filter:
1) .Filter painting and filter printing is not clear enough.
2) .There isn’t bypass-valve in the inside of oil filter , once blocking , the engine will not get enough oil lubrication.
3). Cold starting, the engine wear will be even greater if it did not prevent oil returning after flame out.
4) if the oil filter gasket is made of bad sealing material ,that could cause oil leakage, even fire under the high temperature and pressure.
5) different oil filter paper material, predetermined filtering will be effected .
6) if the oil-through metal mesh is rough, it will be difficult to ensure a sufficient amount of oil pass.
 
Choosing the right oil filter , it will have an important impact on oil and engine, so consumers should be careful when facing the mess filter market.