Understanding Fuel Contaminants
By Tom Bock
As we start a new year it may be a good time to review some of the basics of oil sampling and why sampling should be an integral part of any preventive maintenance program.
While oil analysis is not required for a cyclical oil drain interval program as oil is drained at a predetermined mileage or hours of use, it will provide valuable information that will improve any preventive maintenance program. The sample results will:
• identify potential engine problems
• confirm the oil purchased is oil supplied by vendor
• provide documentation for warranty claims
• identify systematic issues for fleets
• Document driver abuse and/or negligence – low oil levels etc.
• Enable users to compare various oils, etc.
There are a variety of oil sampling programs from desktop testing to comprehensive oil analysis that included all the wear metals, contaminant metals, additive and physical properties. A desktop will be less expensive and provide basic wear metals, (iron, lead, aluminum, copper) and some physical properties (viscosity, soot, fuel) but will not provide the necessary information to extend oil drains.
A high quality comprehensive oil analysis is not only important it is essential for any extended oil drain program. The proper analysis of PHYSICAL PROPERTIES (water, viscosity, soot, fuel, total base number, oxidation, nitration), WEAR METALS (iron, chromium, nickel, copper, lead, tin, cadmium, sliver, vanadium), CONTAMINANT METALS (silica, sodium, potassium) MULTI-SOURCE METALS ( titanium, molybdenum, antimony, manganese, lithium, boron) and ADDITIVE METALS (magnesium, calcium, barium, phosphorus, zinc) provides the information necessary to ensure the oil quality is properly maintained to extend drain interval. The analysis also provides documentation of oil quality and a historical record of wear metals and ensures there are no potential damage causing intrusions i.e., fuel or glycol, affecting oil and engine performance etc. The oil sample results enable user to drain oil only when required as dictated by the oils condition, maximizing the oil life.
Reading an oil sample result is usually simplified by the analysis company by providing a narrative that helps to guide maintenance decisions. The reports will indicate wear metals in a part per million (PPM) format, knowing the age of the engine and mileage on the oil will help the lab determine the ppm per 1000 miles comparable to normal wear patterns for engine. Every engine will have some wear with the majority of the wear coming from lead as this is a key element of bearings. The purpose of bearings is to protect the iron parts from excessive wear and premature failure. While a spike in lead may indicate a pending problem the lead wear is evident in almost all samples. It is the combination of wear metals and or physical property items that will help guide the maintenance requirements. For example high aluminum and fuel dilution usually means the fuel pump is failing with gears wearing and seals allow fuel to enter oil. A sample with high soot and silica usually indicates a clogged air filter that is restricting air flow causing the fuel to air ratio to be altered and causing unburned fuel. High copper tin , sodium and potassium usually indicates a defective oil cooler or EGR cooler.
At OPS we understand that the samples can be confusing and we have a program whereby we call all customers that have a severity 3 (abnormal) or severity 4 (critical) sample report. We want to ensure that they have received the sample results and help guide them with maintenance suggestions etc.
If you have any questions about oil sampling please send a copy of the sample results to: firstname.lastname@example.org with your phone number and I will contact you to discuss the report
The bottom line is an oil sample is an inexpensive way to ensure engine properly maintained and functioning as designed. Start a program today if you do not sample regularly now.