Space Dust

Here’s a fact. Everything we turn up in analysis of your used oil had to get in there somehow. As obvious as that may appear, I hadn’t really thought about it until I ventured into making my own oil.

I built it up gradually, starting with a 10W base stock that was nothing more than refined mineral oil with nothing added. After running it a specific period and measuring the results, I started adding components, running the same miles, and repeating measurements. Eventually I ended up with a complete package that performed very nicely.

Every time I changed something in the oil, the results were measurable. That led to a low-level Eureka! — an affirmation of something I’d always known but hadn’t given much thought: Everything we find in oil analysis had to get in the oil somehow. What we find in oil was put there by the oil blender, came from the engine, or came from the environment.

There are many factors and variables to consider in how long you can use oil in an engine and in how long an engine will last. The most important of all those variables is keeping the oil, regardless of type, as clean as possible. Your air and oil filtration systems are critical players in accomplishing this mission.

The importance of air filtration

Leaving oil filtration for another article, just how important is air filtration? It is one of the most important factors in long-lived engines and long oil change intervals. It is a variable you can control.

Silicon is everywhere in the environment. We rarely think of it unless we see a dust storm in a desert or watch a farmer’s tractor operating in a cloud of dust, but there is no such thing as clean environmental air. If you let rain drops dry on your car or truck, by the time they dry they will have collected enough dirt to leave spots on your paint.

Dirt exists everywhere because it comes from outer space. Have you ever wondered why the most important tool in archaeology is a shovel? If a team of archaeologists went to study a 2000-year-old humanity site, they probably would have to dig down 30 feet to find what they were looking for. The reason old things are buried so deeply is that the Earth is constantly being showered by extraterrestrial dirt. You can’t escape it, even at high altitudes, and they only way you can prevent it from prematurely wearing out your engine is to collect it in an efficient air filtration system.

Controlling the dirt

I was recently speaking with a pilot about why his engine was wearing so poorly. He told me he liked to pull a little carb heat (in other words, unfiltered air) through his engine once he hit altitude because the air up there wasn’t a problem. Once I looked at his report, I saw his silicon level was quite high. He was wrong about the air up there not being a problem. In fact, there is enough silicon in the air at any altitude to cause poor engine wear. It’s important for any engine to filter the dirt out before it can do damage.

All engines wear and eventually wear out. Assuming a mechanical or contamination event doesn’t cut short an engine’s life, the amount of wear an engine’s parts leave in the oil is predictive of how long that engine will last. One of the most destructive contaminants that get into the oil is excessive silicon. The best wearing (longest lasting) engines we see have air filtration systems that keep silicon to a minimum in the oil. Regardless of the air filtration system manufacturers supplied for your engine, it is up to you to maintain it to perfection. Is your air filter up to snuff?

By |2024-09-19T09:44:18-04:00July 28, 2023|Articles, Gas/Diesel Engine, Marine|Comments Off on Space Dust

The Silicon Question

In one of the early years of our business, we were visited by a gentleman from another laboratory. I remember him standing in our lobby emphatically stating that the element silicon – when it appears in the spectrometry of oil – has one source and one source only: abrasive dirt.

He was wrong. Many people believe silicon only comes from dirt, but myriad sources of silicon exist. In oil analysis we look at elements rather than molecules, so silicone from harmless sealers and silicon (no “e”) from abrasive contaminants will both read as the elemental form of silicon. We use deductive reasoning to determine whether the silicon is abrasive or not, and sometimes the answer isn’t entirely clear just by looking at the data. In those cases we’ll cover all the bases and talk about the different sources of silicon and offer a variety of suggestions on how to proceed. Some forms of silicon will harm an engine, and others will not.

Harmless silicon

Silicone-based gasket sealers used in engine assembly and repair show up as high silicon in an oil sample. Any oil sample taken from a new, rebuilt, or repaired engine typically reads high in silicon. Oil from some types of new engines may contain as much as 400 ppm silicon. You can ignore the high silicon in these cases since it is harmless and will wash away by the third or fourth oil change.

Certain brands of engine oil and aftermarket oil additives contain silicon as an anti-foaming additive. The oils that use silicon as an additive can use up to 15 ppm of silicon or so, and we’ve seen silicon in aftermarket additives reading up to 850 ppm. It’s always important to let us know what oil brands and additives you’ve used so we can take that into consideration when writing your comments.

Your sampling procedure might introduce some silicon to the oil as well. The silicon might be from dirt around the drain plug or from a dirty collection pan if you’re dipping the sample out of the pan after you drain the oil. We’ve seen silicon read at several hundred ppm from using new plastic tubing or turkey basters to pump/collect samples. Silicon introduced in the sampling process is harmless to the engine internals.

Harmful silicon

Silicon can read high in an oil when coolant seeps into the oil system. It comes from silicon (rust) inhibitors used in the antifreeze. While the inhibitors aren’t necessarily harmful, the antifreeze certainly is, and you will want to seek repairs before the engine is seriously damaged.

Finally, there’s the abrasive form of silicon: dirt. Abrasive contamination causes poor wear in the cylinders, so if you see high silicon and poor cylinder wear, chances are good the silicon is abrasive. Check the air filter: Is it dirty? Installed properly? Check the seals and connections to make sure they’re properly sealed. Check the air box for rodent or insect nests, particularly if the engine hasn’t been started in a while. Look for cracks or leaks in the induction tubing. In aircraft engines, check the carb heat/alt air doors to ensure proper sealing.

Silicon has several possible sources in analysis. The more information we have about recent engine work, oil brands, aftermarket additives, and your sampling procedure, the easier it is for us to work with you to help determine whether the silicon is abrasive and what steps you should take to protect your engine. At Blackstone Laboratories, our analysts consider all these factors when making recommendations to help you prolong your engine’s life. In the end, that’s what it’s all about! 

By |2024-09-18T14:25:15-04:00July 12, 2023|Aircraft, Articles, Gas/Diesel Engine, Industrial, Lab Tests, Marine|Comments Off on The Silicon Question
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