Your email address will not be published. Save my name, email, and website in this browser for the next time I comment. Additives Cause Blackness Engine oil also includes additives — chemical compounds designed to improve lubricant performance. Warning Signs Just as motor oil will gradually transition from amber to black, there are other signs that an oil change is necessary.
Categories Maintenance Tags car care , engine oil , lubrication , motor oil , oil , oil change , oil filter , synthetic oil. Related Articles. Matthew C. Leave a Reply Cancel Reply Your email address will not be published. Ride quality: How to make your car more comfortable. Water spots: How to prevent them from occurring. Windows fogging up: How to prevent this from happening. Push-starting your car: How and when you can do it. Petrol cars produce lesser carbon soot.
The Oil turns black simply due to carbon byproduct of combussion and dirt. A good oil filter will keep some of the dirt at bay, but the carbon buildup is inevitable. Dont worry about it, TSK. Exhaust emission readindgs are the key to understand whats happening inside engine If we can manage to bring down HC level then we can have good engine oil life Changing the fuel changes the emission This is an excellent reading for exhaust analysys I was told the reason oil turns black is because drops of petrol mix with oil in the combustion chamber , this is becos' the tolerance level in the gap between the rings and the chamber are not accurate, this tends to turn the oil black.
I have a WagonR and have noticed this too. When i top her up with Castrol Magnatec, the oil has a honey color, but after Kms, it turns brownish. In that case what is the interval one should change oil. Also this means that we cannot decide when to chanhe the oil, based on the color. I have to check the viscocity thickness? Okay, so I guess nothing to worry.
One more question, what happens when you use an Oil meant for Low Sulpher diesel with high sulpher diesel the kind available in India? Ok fellows, all my queries are now solved. E-II engines require low sulpher diesel type II which is 0. Usage of API-CJ4 which is not available as of now which will come in will protect my engine better, but ppm sulpher content will damage oil more quickly.
Both bearing arrangements use ring oil-lubrication with bronze oil rings submerged into the bearing oil sump. Figure 1. Other bearing arrangements are present in single-stage overhung pumps, which use matched degree contact angle ball bearings for the thrust and radial bearing, and either a deep groove ball bearing or a cylindrical roller bearing for the radial bearing Figure 2.
The bearings are mounted in a common housing and use ring oil-lubrication with bronze oil rings submerged into the bearing oil sump. Figure 2. Within a period of only a few months, a number of field reports of black oil formation were reported. This phenomenon of black oil is defined as the process by which the lubricating oil darkens or turns black within a time period ranging from one hour to several weeks.
In the case of the overhung process pump, there were reports of both black oil formation and significant amounts of bronze found in the bearing oil. Figure 3 is a typical oil analysis report. Figure 3. However, no single cause of the degradation could be isolated from the field report data. To determine the causes of the phenomenon, a full investigation was performed.
To help identify all possible issues that could contribute to the phenomenon, several groups within the company carried out reviews. All issues identified were then reassessed and compiled to form a problem matrix Figure 4. Figure 4. The matrix listed all the potential causes of the phenomenon that merited further investigation or testing.
For clarity, the matrix was then subdivided into three issue groupings:. Cleanliness-related issues. Issues related to contamination during manufacture, assembly or operation.
A combination of several issues was believed to have been contributing to the black oil formation. By using the matrix as a guide to the investigation, however, it was thought that many of the possible causes could be eliminated early, allowing resources to be focused more on the real issues. The issues listed in the matrix were therefore examined in detail to determine their significance. Some issues were reviewed using data gathered from the field, such as oil samples and replaced bearings.
Other issues had to be evaluated using in-house testing. Because it is possible for oil to react with other chemicals present in the bearing housing, chemistry-related causes for black oil formation were considered.
Known examples of this phenomenon include reactions between some oil additive packages and the rolling element bearing. Therefore, the tests were designed to identify if there were any such reactions occurring within the bearing housing assembly. Three issues were identified in the matrix as being possible contributors to the black oil. They were reaction of the oil with the preservative corrosion inhibitor used inside the bearing housing, reaction of the oil with the sealing paint used inside the bearing housing, and changes in the lubricating oil and additives.
Cleanliness of the lubricating oil is of great concern. If the oil or the system into which it is placed is contaminated, the contamination will be circulated through the rolling element bearings. These bearings are easily damaged by particles passing through them or by corrosion caused from water in the oil. Two issues identified in the matrix as being possible contributors to black oil were housing cleanliness after manufacture and contamination during operation.
It was concluded that neither of these issues contributed to the oil blackening or the bronze in the oil. Five wear-related issues were identified in the matrix as being possible contributors to black oil.
These were oil ring stability and immersion depth, bearing fit, bearing type, low oil delivery to the bearings, and oil viscosity and additives. To determine the significance of each of these issues, an in-house test program was established.
The test program consisted of 13, two-hour and seven, eight-hour tests and was carried out on a custom designed test rig. The rig was able to apply radial and axial loads to an assembly duplicating the configuration of the between bearing pump Figure 5.
Figure 5. Plexiglas viewing windows mounted into the bearing housing and temperature probes allowed personnel to observe the complete behavior of the bearings being studied.
0コメント