Last oil analysis showed a nitration Level at 25 A/cm.. the oil have 6000 miles on it, just a standard 5W-40 syntetic oil. My question is, should i be concerned? The lab told me: "Some nitration... Just change the oil"
Nitration level
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I have not found a lot to read on nitration levels in a UOA except people who are running natural gas engines are the ones mainly concerned about nitration levels. Most UOAs (except Polaris and OAI) do not provide oxidation and nitration.
Ask the lab for more details about it.
What kind of vehicle/engine?
Ask the lab for more details about it.
What kind of vehicle/engine?
Originally Posted By: Donald
Most UOAs (except Polaris and OAI) do not provide oxidation and nitration.
Wearcheck provides it, too. But it was never flagged on any of my reports and I'm not even sure what level would be considered abnormal.
Most UOAs (except Polaris and OAI) do not provide oxidation and nitration.
Wearcheck provides it, too. But it was never flagged on any of my reports and I'm not even sure what level would be considered abnormal.
I know zilch, but check this out:
http://machinerylubrication.com/Read/30020/engine-oil-nitration
It seems there are a few basic things to check that might reduce it for the next round.
http://machinerylubrication.com/Read/30020/engine-oil-nitration
It seems there are a few basic things to check that might reduce it for the next round.
Watercooled Porsche 911 3.8 litre, i did find a tread here at the forum about nitration levels: Excellent would be under 10%, good would be 10-20, satisfactory would be 20-50 and 50 or higher would be poor. Based on a 5-6k interval.
It can be many causes to nitration:
Exhaust Gas Scavenging Efficiency
Better exhaust gas scavenging (removal of exhaust gases from the combustion chamber), as would occur in turbocharged units, reduces the interaction of NOx with the oil and decreases nitration.
Cylinder Wall Temperature
The reaction between NOx and the oil, which causes nitration of the oil, occurs partially on the thin layer of oil on the cylinder wall. The liquid nitration products that form in the oil are apparently destroyed at cylinder wall temperatures greater than 150 degrees C (300 degrees F). Therefore, lower cylinder wall temperatures are needed for oil to nitrate. These lower temperatures are more common in lower speed and naturally aspirated four-stroke engines.
Piston Ring Efficiency
Reduced blow-by lessens NOx contact with the oil in the sump. Blow-by of combustion gases into the crankcase adds to a buildup of nitro compounds in the oil. When ring sealing is poor, more highly nitrated oil will migrate back into the crankcase instead of out through the exhaust port.
Crankcase Ventilation
Better crankcase ventilation has the same effect as improved scavenging by reducing the contact between NOx and the oil.
Oil Sump Temperature
Nitration of the oil from NOx in the blow-by gases that enter the sump increases at lower oil sump temperatures, i.e., below 80 degrees C (175 degrees F), and increases as sump temperatures approach 70 degrees C (160 degrees F). This is different from oxidation, which increases with temperature and becomes significant at oil temperatures greater than 90 degrees C (190 degrees F).
Base Oil Type
Certain base oil types are more susceptible to nitration than others. Base oils with saturated hydrocarbon structures, such as polyalphaolefin (PAO) synthetics and hydrotreated paraffinic oils, seem to be less prone to nitration. Lower viscosity base oils and viscosity index improver additives used in some multigrade oils may be more likely to experience nitration.
Rate of Oil Makeup
Oil makeup does not reduce nitration, but it does dilute the nitrated oil with fresh lubricant. The higher the oil makeup rate in a given engine, the slower the rate of oil deterioration detected in the lubricant.
Spark Timing
While evidence exists indicating that spark timing influences nitration, there are no defined studies on its impact.
Air/fuel Ratio
Low rates of nitration may be maintained if the oxygen level in the exhaust is outside the range of 0.5 to 4.5 percent, with nitration reaching a peak at nearly 3.3 percent oxygen.
Load
Field tests have shown that nitration increases when ambient air temperatures rise and/or engine loads are higher.
Using these factors, you can prepare a troubleshooting guide and inspection/verification list to help control nitration in your engines.
I did have an catalytic converter breakdown in this interval, and it did affect the Air/Fuel ratio, i get the check engine light as well, that maybe explain the higher nitration Level. Previous UOA show nitration at 11 A/cm
So the next UAO will be the Rabbit hole, Valvoline Synpower 5W-40
Thank you all for answers
It can be many causes to nitration:
Exhaust Gas Scavenging Efficiency
Better exhaust gas scavenging (removal of exhaust gases from the combustion chamber), as would occur in turbocharged units, reduces the interaction of NOx with the oil and decreases nitration.
Cylinder Wall Temperature
The reaction between NOx and the oil, which causes nitration of the oil, occurs partially on the thin layer of oil on the cylinder wall. The liquid nitration products that form in the oil are apparently destroyed at cylinder wall temperatures greater than 150 degrees C (300 degrees F). Therefore, lower cylinder wall temperatures are needed for oil to nitrate. These lower temperatures are more common in lower speed and naturally aspirated four-stroke engines.
Piston Ring Efficiency
Reduced blow-by lessens NOx contact with the oil in the sump. Blow-by of combustion gases into the crankcase adds to a buildup of nitro compounds in the oil. When ring sealing is poor, more highly nitrated oil will migrate back into the crankcase instead of out through the exhaust port.
Crankcase Ventilation
Better crankcase ventilation has the same effect as improved scavenging by reducing the contact between NOx and the oil.
Oil Sump Temperature
Nitration of the oil from NOx in the blow-by gases that enter the sump increases at lower oil sump temperatures, i.e., below 80 degrees C (175 degrees F), and increases as sump temperatures approach 70 degrees C (160 degrees F). This is different from oxidation, which increases with temperature and becomes significant at oil temperatures greater than 90 degrees C (190 degrees F).
Base Oil Type
Certain base oil types are more susceptible to nitration than others. Base oils with saturated hydrocarbon structures, such as polyalphaolefin (PAO) synthetics and hydrotreated paraffinic oils, seem to be less prone to nitration. Lower viscosity base oils and viscosity index improver additives used in some multigrade oils may be more likely to experience nitration.
Rate of Oil Makeup
Oil makeup does not reduce nitration, but it does dilute the nitrated oil with fresh lubricant. The higher the oil makeup rate in a given engine, the slower the rate of oil deterioration detected in the lubricant.
Spark Timing
While evidence exists indicating that spark timing influences nitration, there are no defined studies on its impact.
Air/fuel Ratio
Low rates of nitration may be maintained if the oxygen level in the exhaust is outside the range of 0.5 to 4.5 percent, with nitration reaching a peak at nearly 3.3 percent oxygen.
Load
Field tests have shown that nitration increases when ambient air temperatures rise and/or engine loads are higher.
Using these factors, you can prepare a troubleshooting guide and inspection/verification list to help control nitration in your engines.
I did have an catalytic converter breakdown in this interval, and it did affect the Air/Fuel ratio, i get the check engine light as well, that maybe explain the higher nitration Level. Previous UOA show nitration at 11 A/cm
So the next UAO will be the Rabbit hole, Valvoline Synpower 5W-40
Thank you all for answers
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