How do oil filters remove water?

Not all filters are created equally - cellulose (paper) filters in oil systems are able to absorb some water while excluding oil. This is all down to the cellular structure of paper, which is hydrophilic.
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[@metinsimsek6964]

Thank you for the information. Cellulose filter elements will collapse and lose filtration capability as they absorb water. It is not very effective when water is emulsified. SO it is not very effectiveto use cellulose when there is water in oil. Remember, water is always emulsified in hydraulic systems due to re-circulation through pump.

Hi. Thank you for the videos. My knowledge is not complete but as far as i know we run our internal combustion engines at high enough temperatures because we want the water in the oil to evaporate. This is how know it. What i wonder is, wouldnt it be a better if we keep the oil temperature way cooler but filter the water another way? Wouldnt it be much bettter for the service life and the lubrication performance of the oil?

[@Maklaaad]

Filters Pic is for home water filters

[@LubricationExplained]

True! This is actually one lessons in a whole course on water removal technologies. The picture makes a bit more sense when you see them all together.

[@CJ5EVOLUTION]

What happens when that paper element gets saturated, what interaction happens with flow of oil.

[@ReteteGratuite]

Interesting! Now i have a question. This also apply to fuel filters right? And some say to change fuel filter after 30k kilometers which means in average 2000 liters of fuel pumped trough the filter. Isnt that a bit to late? I think the filter will be already water saturated (specialy in cold climate with condensation) and the fuel injection system will suffer. What do you think?

[@ReteteGratuite]

at least in indonesia where you said that biodiesel can be 30% in diesel. and contains more water practicaly

[@imperialnacho4259]

Fuel filters normally don't absorb the water. They seperate it from the Diesel. In these filters the cellulose is coated to acchieve the seperation effect. The water is then led to some kind of collector from where it can be drained. Unfortunately the solid dirt in the Diesel can damage the cellulose coating, which then leads to the cellulose first absorbing some water and then let the water pass when it is is fully soaked. So these filters need to be changed regularly. Source: I work for a filter producer :-)

[@LubricationExplained]

Great answer! Thanks for contributing.

[@ReteteGratuite]

@@imperialnacho4259 Nice info, thanks! So is the 30k km interval ok from your point of view?

[@metinsimsek6964]

@@imperialnacho4259 cellulose filter elements absorb water in fuel and gets destroyed. This is a common problem. Water separator is different issue. Separators are not effective when water exists in micronic sizes.