Silicon – What is it and how did it get there?

Feb 4, 2014 | breathers, coolant analysis, dirty fuel, fuel analysis, grease analysis

Hi Tech Bloggers, Over the past few days we spoke about Water in Oil, so why not continue with some other contamination issues we might find in our oil sample, let’s look at  Silicon (Dirt/ Dust) entry.

What is Silicon? Silicon is a chemical element known as Si and atomic number 14 in the periodic table. Silicon is a tetravalent metalloid which means it is a mixture of metals and nonmetals, simular to boron, germanium, arsenic, antimony and tellurium. There are no standard definitions that classify these metalloids as being either a metal or nonmetal. Silicon is the eight most common element found within the universe by mass and the second most abundant element found in the earth’s crust.  So there is plenty of it and we need to be well aware that it has the capabilities of causing many problems with equipment components.

Silicon is not silicones, silicone is a synthetic compound used in sealants, adhesives, lubricants, and other various uses. Silicone is a rubber like compound and should NOT be confused with silicon.

How does Silicon get into my oil? Well this is the million dollar question. There is only one way that you could have found Silicon in your oil, and that’s by having an Oil Sample analysed.

If the Silicon wasn’t put there on purpose, such as in the oil manufacturing process, then you can be sure it is a contaminant in your oil and you need to be concerned if you have higher than normal amounts, this will be displayed in your oil analysis report.

Some oils contain silicon as an additive, a virgin oil sample (New Oil) needs to be taken and analysed to ensure this is not the case.  

Some TIPS you need to be aware of when taking your used oil sample:

  • Ensure your bottle, cap, lid, plastic bag are all clean and dry
  • Ensure your sampling apparatus is also clean and dry
  • If you are using sample tubing, ensure you don’t rub the side or bottom of the sump, plate or side of a dipstick as this can cause the sample to contain build-up or unwanted high readings in silicon and other elements.
  • When checking your oil, ensure you always use a clean dry rag and wipe the dipstick prior to placing back in the clean oil. This is a common mistake made by many, placing the dipstick on dirty surfaces and then putting it back in the clean oil.

 The last thing you want is to contaminate your own oil sample.  

Silicon can be caused by your air filter or breather being blocked (Dirty), clogged, broken or simply too old and needs to be replaced.

  1. Air filters and breathers are certainly the first thing you should check. Defective air filters and breathers can cause missing or rough idling, smoke from your exhaust, back firing, increased fuel consumption, overheating, foaming and many other problems.
  2. The second thing that needs to be checked are the seals, broken, torn, melted or even missing seals can cause unwanted dirt entry, again this can cause issues to the oil, external and internal components.
  3. The third thing we must do is check our oil filters and ensure they are being changed out at the correct intervals. Warn or clogged oil filters can do extreme damage to the entire component. Loss of oil flow and film strength will no doubt be the end for that machine.

It’s not only our oil we need to be concerned with, Silicon also has a tendency to get into Fuel, Coolants and greases. Once we have contaminated lubricants, you be sure that damage will soon occur. Silicon is an abrasive material and will accelerate wear, dependent on the size and quantity of the particles will determine the extent of the damage.

Components are built with minimal clearances and designed to have a film of lubricant to separate the two surfaces and provide an even load. Once a particle flows through these two surface boundaries, it will most likely cause contact to occur, this will create friction and an unbalanced load. Once this has occurred, then issues like high aluminium, copper and iron readings may be seen in your oil analysis report, indicating that there has been contact with internal components and is accelerating and causing further unnecessary wear.

We would need to then go back to the start and find the cause of the silicon entry and rectify the issue. An oil change would be necessary to rid the contaminated oil. Once repaired we need to resample to ensure the dirt entry has been stopped and there isn’t going to be a reoccurrence.

If you would like to find out more or have any questions, please contact us

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