How To Detect Water In Oil

If you are a working with any kind of engine oil then it would be very important query for you.

As most of the engine needs water or water types fluid such as coolant. So there always a big chance to mix water in the engine oil which might be harmful for the engine or equipment if the water in oil is significant level. So lets discuss about how to detect water in the oil.

How To Detect Water In Oil
Water In Oil

Firstly you have to know the methods of how to detect water in oil. Though the most widely used method to detect water in oil is Karl Fischer (KF) which is generally done by ASTM D6304 method. And the other methods are:

  • Crackle test
  • Calcium Hydride Oil Analysis
  • Infrared Spectroscopy
  • By Relative Humidity Sensors

Lets discuss about some common & easiest methods to detect water in oil:

Crackle test procedure:

If you ask, how to detect water in oil then you will see, the answer is that, crackle test method. Its is the only easiest way to detect water in oil in a simple laboratory. In this method water mixed with oil placed on a hot plate. & then burn up to 400 F. Then if there is any water in the oil it becomes bubbles ,crackles, or evaporates with sounds. The percentage of water has to determine by visual inspection. It is the shortest and most effective method to detect water in oil. But if you want to find the accurate percentage of water or want to remove water from oil then it may not be perfect for you.


  • It is very easy test for detect water in oil
  • You can also remove water from oil by the crackle test oil.


  • Accuracy is not possible in crackle test, this suitable for visualization of water in oil.

Infrared Spectroscopy:

In this procedure measurement is done from the interaction of organic molecule. This interaction would be radiation, absorption, emission or reflection.

How to detect water in oil by infrared spectroscopy:

In this method, you will get the exact measurement of water with the perfect detection from an oil sample. But it might not cost effective for you, as you need an IR spectrometer for this method. In this method, a small amount of sample has to collect by syringe carefully & inject into an extractor. Then have to place this extractor into the spectrometer along with the card. After pressing the start button you will get the detected water amount with spectrographs within a very short time in the display or connected computer.

You can visualize the full process by the video appended below: 

This is very popular method for getting the Moisture content of oil determination or Oil in water ppm calculation. In a word this the only professional method for detect water in oil or oil in water.


  • This process is so first.
  • You will get the accurate data by this test.
  • There is almost no physical activity needed in this test as it is mainly done by spectroscopy.


Infrared Spectroscopy test is not cost effective for detect water in oil.

Karl Fischer method: 

This is the  most widely used method to detect water in oil or another compound. It is an analytical procedure to detect & quantify the amount of water content of any type of product or chemical. This process is done by titration of volumetric or coulometric application. The basic principle of this method is the oxidation reaction of iodine & Sulphur dioxide.


  • It gives super accurate results
  • Both qualitive & quantitives research are possible in by Karl Fischer analysis.
  • This test is a chemical reaction base test so It’s cost is not beyond control.


  • Karl Fischer volumetric analysis sometimes gives marginal error & coulometric analysis is suitable for small samples only.
  • Water detection is not possible from some chemicals like aldehyde, ketone by KF analysis.
  • Wastage of solvent due to manual titration in volumetric process.

Final World:

Hopefully you have learned a lot about how to detect water in oil. Now you have to chose your analysis according to your requirement. If it is for your query only then go for crackle test oil, but if it is for professional purpose you may go for IR or KF analysis.


Emon is Lubricants specialist who studied on Petroleum Engineering in UAE. He have more than 10 years experience on different kinds of lubrication including automobile troubleshooting.