Contamination testing is split into a number of different individual test. We will perform:
The Karl Fischer test measures the exact amount of free and dissolved water molecules contained in the grease sample. The Karl Fisher test is reported
in a numerical value.
Used as a corrosion inhibiter, anti-wear and anti-oxidant additive. Concentration levels vary greatly depending on grease brand. Also Boron is used
in extreme pressure compounds and dispersants. It can also appear as a contaminant as it can be used in the manufacture of coolant conditioners.
Boron can come from a few areas; it can come in with water, coolant, from worn seals or airborne dust.
Silicon is usually seen as an indication of dirt entry however it can have many different sources. Silicon is part of a chemical added to oils to stop
them foaming so silicon can be an additive. It is usually found in a concentration of 5 to 10 ppm, so do not be surprised to see silicon in new engine
oil samples. Do not panic, this is not due to dirt. Silicon is found in chemicals used in coolant conditioners so it can show up as a contaminant if
there is an internal coolant leak, along with sodium.
The most common chemicals contain sodium so this is the first indication of an internal coolant leak. Other chemicals found in coolant conditioners
contain elements such as molybdenum, phosphorus, chromium, boron and silicon. Elements that make up the physical structure of the cooling system and
can leach into the oil (from either the water or the oil side of the cooler) include copper, tin, lead and silver. Sodium can also be found as an
additive in some engine oils (often replacing calcium or magnesium) but this is a lot rarer than it used to be. Some greases contain sodium as part
of the soap and sodium will be evident if the oil is contaminated with sea water.