OIL AND YOUR ENGINE PON-CAT.COM/KNOWLEDGE

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1 OIL AND YOUR ENGINE

2 OIL AND YOUR ENGINE Engine problems due to bad motor oil Broken bearings, sticking piston rings, and high oil consumption: these are all symptoms of engine problems associated with the condition of the motor oil. Three things ensure that oil is in ideal condition: use of the right type of oil, regular maintenance of the oil system and systematically monitoring the oil. The testing of oil samples gives you insight into the state of the engine and an early warning of potential problems. You can then take preventative measures to avoid engine problems. What does motor oil do? Motor oil ensures there is adequate lubrication to keep the engine clean and free from corrosion. Motor oil cools the engine and creates a thin layer of oil on metal parts. This reduces friction and wear. But, these are just the basics. Motor oil performs other functions depending on how and under what circumstances it is used. This also makes it critically important that the right type of oil is chosen. In addition to basic motor oil, there are many other types of motor oils with different additives. Types of motor oil Mineral oil is made by refining crude oil. This type of oil is most often used in diesel engines because of its proven track record and that it is reasonably priced. Synthetic motor oil is made using a chemical process. Compared to mineral oils, a characteristic of synthetic oil is that it thins less quickly at higher temperatures and this provides the engine maximum protection under the most extreme conditions. Additives Additives enhance or alter characteristics of the basic motor oil. This allows a basic motor oil to meet specific requirements that it otherwise could not satisfy. For example, detergents can be added so that the engine is kept clean. There are also additives that neutralize acids, others that withstand an increase in viscosity, and others that reduce wear on metal parts. Viscosity Oil density is intrinsically critical and is designated by its viscosity. Oil with a low viscosity is thin and oil with a high viscosity is thick. The denser the oil, the thicker the oil layer and the more difficult it is to rub the layer off of engine parts. The SAE (Society of Automotive Engineers) classification is used to designate the viscosity grade. This SAE designation does not reveal anything about the other properties of the oil. The SAE classification is based on the liquidity of the oil at 100 C. If there is a W (=winter) after the number then the viscosity is determined at a temperature below 0 C. So, the higher the SAE number, the higher the viscosity. Why is testing motor oil useful? Conducting systematic motor oil tests allows you to prolong the life of your engine and increase its efficiency. An analysis of motor oil scrutinises four critical issues: Rate of wear of engine parts State of the oil Contamination in the oil Oil identification The motor oil testing is based on periodic laboratory analysis of oil samples. You take a sample of the motor oil at regular intervals and send it to the Pon Power laboratory. Lab technicians then scrutinise the motor oil sample for the presence of signs of wear. For example, if they find a high concentration of iron, chromium or aluminium, this may indicate a damaged piston ring. An elevated concentration of silicon, lead or aluminium may indicate abnormal bearing wear. In other words, motor oil testing reveals the current condition of your engine. Frequency of samples Regularly scheduling motor oil testing is critical for detecting and rectifying of problems and determining the optimal maintenance schedule. Under normal conditions, it is common to take a sample and carry out an oil change every 250 operating hours. When you send in a sample regularly, it increases the likelihood that potential damage or wear can be caught and rectified before it happens.

3 Taking an oil sample using the vacuum extraction method with the dipstick of the oil sump You can take samples from engine systems that are not under pressure using a vacuum extraction pump. It is important to use a new piece of tubing for each sample. Re-using tubing is likely to pollute the new sample. If an engine system that is under pressure does not have a sampling valve then follow the vacuum extraction method described below. NB: Take the sample from a warm idling engine. Rules for correct oil sampling: 1. Keep all equipment clean and free from dust and oil. If oil or dirt still is present on the suction pump then clean it off with a little gasoline. 2. Beforehand, write on the bottle where the sample was taken from to avoid mixing up the bottles when taking more than one sample. 3. Use a new piece of tubing for each sample. 4. Take the appropriate amount of plastic tubing and cut it diagonally. Insert the tubing into the vacuum pump so that the tubing sticks out about 1 cm under the black screw cap and clamp the tubing tight with a locking screw. Make sure the tubing remains free of oil and dust. 5. Then, screw the sample bottle onto the pump. Place the end of the tubing into the sump making sure that the end of the tubing does NOT touch the bottom of the sump. 6. Use the suction pump to fill the bottle to the indicated level (about 90% of the bottle volume). Make sure that you keep the bottle upright when the pump is running. Now shut the bottle tightly and wrap it in the supplied plastic bag. 7. Before pulling the tubing from the pump, first use a clean cloth to clean the tip sticking out under the black screw cap. This keeps your vacuum pump clean. 8. Fill in all the information required on the sample label. This is made easier by keeping a log book to record number of operating hours, oil change, interim replenishment, and so on. 9. Put the oil sample with its completed sample label in the shipping envelope and seal it using the supplied fastening clip. 10. No stamp is necessary, except when shipping from abroad. 11. An oil sample should be taken from all compartments every 250 operating hours and immediately before each oil change. Taking an oil sample via sampling valves This method requires a copper probe and about 15 cm of tubing. It is important to use a new piece of tubing for each sample. Re-using tubing is likely to pollute the new sample. 1. Run the engine until the engine reaches operating temperature. Run the motor at a low idle speed. Remove the dust cap of the valve and wipe it clean with a clean cloth. 2. Insert the copper probe into the valve and extract about 100 ml of oil into a waste container. If the oil runs slowly at the start then have someone run the engine at a higher idle speed while you are taking the sample. Dispose of waste oil in the appropriate manner. This process cleans the valve. 3. Insert the copper probe into the valve again and fill the sample bottle to the mark. Do not fill to the top. Make sure dirt does not end up in the bottle or cap. 4. Remove the copper probe from the valve and close the bottle cap tightly. Seal the bottle in the provided sealable plastic bag and put this with the filled in label into the envelop that has our freepost number on it. To avoid contamination, do not take samples from the drain stream, a waste oil container or a used filter.

4 ANALYSIS REPORT Required Information (Sample Data) The information in the report is based on the data you have filled in on the sample label. The information required for the assessment of your oil: Company name Engine serial number Number of hours of operation of the engine Number of hours that the oil was used Brand, type and grade of oil Engine make Engine model Compartment Notes and miscellaneous information Information on the label is used to record the sample in our database. This provides the history of your engine for your report. Information on the label also contains important data needed to interpret the results so that the best recommendations can be made. Laboratory check number (Sample Number) The laboratory check number is a unique number for your sample. This number helps the lab to trace the sample during the various analyses. Overall evaluation The overall evaluation is colour coded to indicate the urgency of required actions. Review the red codes first, which are the most urgent. Then review the yellow codes. Last, review the green codes. Interpretation (Evaluation & Recommendations) The interpretation section provides a summary of the findings of the oil analysis and makes appropriate recommendations. One recommendation might be to take samples at shorter intervals to verify the findings and keep a closer eye on wear. OVERVIEW OF THE RESULTS OF THE MOTOR OIL ANALYSIS Results of the motor oil analysis The results of oil analysis are shown in this section of the report. The name of the test and the results are reported separately. The totals from the element analysis are listed. The test results are described further below. Explanation of abbreviations The abbreviations used in the oil report are explained at the bottom of the report. Rate of wear of engine parts (Wear Elements) The oil analysis results are used to evaluate the wear. Using a trend analysis and our own wear tables, we can determine whether the magnitude of the wear is normal or abnormal.

5 Analysis of particles present in the engine oil The results of the particulate levels analysis are given in parts per million (ppm). This is an indicator of the concentration of particulates in the oil. One iron particle in 999,999 particles of oil is one ppm. Approximate examples of a ppm: one second in 11.5 days, one drop of ink in 150 litres of water. Diesel motor elevated test results Iron, chromium Iron, chromium, aluminium Lead, aluminium, iron Sodium, potassium, copper Silicon greater than aluminium, iron, lead Soot, iron, lead, chromium Potential sources Cylinder packing, piston rings Cylinder packing, piston rings, aluminium pistons Lower connecting rod bearing and main bearings, crankshaft Coolant contamination Dirt, cylinder packings, piston rings, bearing surface Soot wear on cylinder packing, piston rings, bearings CONDITION OF THE OIL Whether to replace the motor oil or not An analysis of the condition of the motor oil is used to determine whether the oil is still in good condition. Tests are conducted to evaluate the viscosity and formation of oxidation, nitrates and sulphates in the oil. All oil lubricated compartments are at risk for oxidation damage. This is why it is recommended to analyse the condition of oil samples from different compartments. Guidelines and trend analyses are used in the motor oil analysis to determine whether the engine oil must be replaced. Viscosity (V100) If the viscosity is too low then wear will occur in the compartment. If the viscosity is too high then the motor oil will not flow to places that must be lubricated. Many oils for diesel engines are developed with characteristics for multiple temperature ranges. At lower temperatures, these oils have a lower viscosity to provide protection when starting the engine. If the viscosity at low temperatures is not correct then the oil will not flow fast enough for components that require lubrication. At normal temperatures these oils have a higher viscosity in order to protect moving parts. Oxidation (Oxi) Oxidation occurs in motor oils when oxygen molecules chemically bind with the oil molecules. This causes a higher viscosity, the formation of acid and the formation of precipitation. Oxidised lubricants in diesel engines lose the ability to protect engine parts. This can lead to piston rings sticking, polishing of the lining walls and abrasion or valves to stick. Sulphate formation (Sul) The sulphur in diesel fuel combines with water during combustion to form sulphuric acid. Lubricants for modern diesel engines neutralize this acid. High concentrations of these acids break down the engine oil and this causes corrosion to valves, valve guides, piston rings and liner. Nitration (Nit) Nitration occurs with all motor oils, but is usually only a problem in engines that run on natural gas. Nitrogen compounds from the combustion process increase the viscosity of the oil and reduce

6 lubricity. Nitration can clog oil filters and cause precipitation on the pistons and varnish on the valves and pistons. Total Base Number (TBN) The acids that arise during the combustion process are neutralised by additives in the basic motor oil to prevent corrosion. However, these additives have a limited lifespan. The acid neutralising capability of the additives can be monitored by analysing the additives. This must not decrease more than 50% of the initial value. Analyzing the basic component is called the Total Base Number analysis (TBN). OIL POLLUTION Guidelines for pollution levels There are also tests to determine whether the oil is polluted. Tests are conducted for the presence of soot, fuel, water and coolant. Guidelines regarding the permissible amount of pollution in the engine are an integral part of the oil examination. Soot (ST) Soot is the insoluble precipitation of small particles of carbon from partially burned fuel. These particles are kept suspended in solution by oil additives and cause the black colour. The soot particles cause abrasion and wear on the engine. Soot levels above the permissible levels will not be kept in solution by the additives. When this happens, larger soot particles are formed. These larger particulates clog oil filters, cause precipitation and increase the viscosity of the oil. Eventually, the wear on the engine will become abnormally high. Fuel dilution (PFc) The main problem caused by fuel dilution is low viscosity. Oil films become dangerously thin at low viscosity and high operating temperatures. If the oil film is not thick enough, parts start grating and can even jam. If the dilution of fuel exceeds the recommended levels, it is usually due to fuel line leakage or worn or failing fuel injectors. Prolonged idling of the engine or incorrect timing are also possible causes. Water (H2O) Water can condense or leak inside a compartment. Water causes wear due to corrosion and rust. When water binds to components in the oil and forms acids it causes wear. Rust can occur in areas above the oil level in fluid reservoirs where there is no oil film to protect the metal. If large amounts of water enter a compartment, the mixture of oil and water form a thick sludge. Coolant Engine oil may become contaminated due to leaks in the oil cooling systems, internal coolant pipes and cylinder heads gaskets. Contamination with coolant will increase the wear. TREND ANALYSIS Trend analysis provides the best indication of the status of the engine. A particular trend can be established by taking three to five samples of the oil from the same compartment over a particular period. It is important that all information on the sample label is properly filled in. If the test result for a sample differs from the established trend that may indicate that there is a problem. Additional samples Occasionally, an additional sample is needed: to better monitor a report with a yellow code to check a result for the previous sample to establish a trend analysis if an insufficient amount of oil was sent to conduct a double check after an engine repair

7 Further questions Sometimes, more information is needed to throw more light on the motor oil results. You will be asked questions like: did you switch to a different brand of oil and/or viscosity? was the engine recently repaired? was the number of operating hours filled in correctly? Recommendations The recommendations from the motor oil report specifically focus on the compartment analysed. The test results are evaluated. If there is a problem somewhere, we will clarify its connection with the test results. We also will identify abnormalities. If the results of the oil analysis indicate it is necessary then we will provide you with professional advice on necessary maintenance or repairs. The condition of your engine be closely monitored using your log book. This allows you to schedule servicing and repairs in a timely manner and prevents unplanned engine outages. S O S TM (SYSTEMATIC OIL SAMPLING) BY PON POWER Pon Power incorporates the latest developments into the motor oil analyses and uses the most advanced measuring equipment. Motor oil analyses are conducted in accordance with ISO 9002 procedures. Our fully automated process ensures a professional and rapid reporting of analysis results. As the official Caterpillar dealer, we can make exclusive use of the manufacturer s data concerning the materials composition and engines wear limits. Contact Pon Power Do you want more information about the S O S analysis by Pon Power? Please call your contact person within Pon Power. You can find the right contact person on our website pon-cat.com/contact or call us at telephone number +31 (0)