This article originally appeared on the P&WC Airtime Blog.
Our expert shares 5 oil maintenance best practices that will help give you a clear picture of your oil status and keep your engine performing optimally.
1. RESPECT THE MIN AND MAX LEVELS
If your engine oil is at a level below the minimum, the oil supply during operation may be insufficient. Conversely, a level that exceeds the maximum may impede proper operation of the air/oil separator or breather, leading to possible bearing seal distress and loss of oil through the engine breather tube.
An oil level that’s too high or too low could also result in oil pressure fluctuations, low-pressure indications and engine damage.
2. MONITOR OIL USAGE OVER AT LEAST 10 HOURS
To perform engine oil system servicing effectively, you should continuously monitor your oil consumption. Careful monitoring will give you advance warning of abnormal oil consumption allowing you to carry out preventive troubleshooting.
For more accurate results, we recommend recording oil consumption data over at least 10 hours of accumulated flight time and plotting the data for oil consumption trend analysis. This will give you a more realistic portrait of your engine’s functioning.
On a related note, be wary of oil level readings taken when the aircraft is parked on uneven ground, since they may not be accurate.
Aircraft attitude may affect engine oil level readings, especially in the case of helicopters, which land on all kinds of uneven surfaces. You shouldn’t use readings taken when the aircraft is resting at an angle.ANDRÉ GALLANT, TRAINING SPECIALIST, FIELD SUPPORT OFFICE
3. ALWAYS PERFORM SERVICING AT THE DESIGNATED TIME
Always check and service your engine oil system at the same time, based on the instructions in the engine maintenance manual. Typically, the designated time is around 15 to 30 minutes after shutdown. This is fundamental to obtaining reliable and accurate oil consumption trend data. If you wait longer than the indicated time to check the oil level, it may affect the readings, since hot oil in a still-warm engine has more volume than cold oil.
Checking the level as recommended by the engine maintenance manual can also help you identify issues. For instance, if you checked the oil level shortly after shutdown, then come back the next morning and notice that it’s notably lower, internal static oil transfer may have occurred overnight.
In a situation like this, do not simply refill the oil tank. If you do, there may be too much oil in the system and it could overflow via the engine breather. Perform troubleshooting instead to resolve the matter. On a PT6A engine, the cause could be a leaky oil filter check valve.
4. USE THE SAME LEVEL EVERY TIME
Likewise, you should always service your oil system to the same level. If you fill the oil tank to the maximum one day and to the minimum the next, it could skew your data. No matter what the oil level indicator configuration is, we recommend always servicing your engine oil system to a level somewhere between the minimum and maximum.
If you keep your oil levels at the maximum all the time, it could increase your oil consumption rate, since some oil has a tendency to exit through the engine breather. This could even happen at one or two quarts below the maximum, so you should adjust accordingly and service the oil system to a level where consumption is acceptable.ANDRÉ GALLANT, TRAINING SPECIALIST, FIELD SUPPORT OFFICE
5. USE THE RIGHT DEVICE AND OIL
When topping up your engine oil tank, be sure to use an appropriate filling device such as a funnel or fluid servicing cart with the appropriate attachment. Using the wrong device could lead to spills and leakages, as well as an inaccurate oil usage recording.
You should also exercise caution when inter-mixing different brands or types of oil and always follow the recommendations in the applicable engine maintenance manual and oil service bulletin. When permitted, switching to another kind of oil might require additional maintenance, such as oil analysis and filter inspection, paying attention to carbon deposits. As different oils may have different properties. And in some situations, such as engines that have accumulated a lot of hours, switching oil type may be prohibited.
The best thing you can do is to stick with the same brand and type of oil. If you have to change, always check the applicable engine maintenance manual and oil service bulletin first to see whether you can and what oil brands and types are acceptable.ANDRÉ GALLANT, TRAINING SPECIALIST, FIELD SUPPORT OFFICE
Putting these handy tips into practice while also following the standard procedures in your maintenance manual will allow you to maintain a normal main oil pressure during engine oil system servicing.
With the help of P&WC’s new Oil Analysis Technology –which is 100 times more sensitive than other oil monitoring technologies on the market –your engine oil can also provide you with insights into the health of bearings, gears, carbon seals and other engine parts. By analyzing data taken from periodically collected oil samples, this technology monitors engine health on wing and supports predictive and preventive maintenance without intrusive inspections. To learn more, check out Oil Analysis Technology Makes Proactive Maintenance Easier.