Due to the fact that oil interfaces with air in the bearing cavities and seals in the accessory gearbox assembly, you should be constantly monitoring the oil level and checking cowlings for leaks.
On some P&W 545A engines, we have seen a few problems in the gearbox seal area. Though it is fairly obvious when a starter-generator or alternator seal leaks, there are other seal areas that leak as much or more and are not as obvious.
As oil consumption approaches one quart in 10 hours, the hydraulic and fuel pump drains are where you need to focus. Oil leaking from these areas and exiting through drain tubes is frequently overlooked.
Another place to monitor is in the bypass duct and on the inner portion of the thrust reverser stangs. As always, reference the appropriate Pratt & Whitney maintenance manual for troubleshooting.
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