Modern turbofan engines are remarkably complex pieces of machinery, so tools for maintaining and repairing them must be specialized to the task. In this blogpost, we’ll break down six types of tools you should always have if you’re performing regular turbofan maintenance.
Oil pressure can be the first indicator of a mechanical issue with your engine. If there is a change in pressure, you’ll need to react by checking the pressure adjustment and cold start valve to make sure that they are both clean and functioning properly. This will require disassembling the springs and pistons, which in turn requires specific tooling, which can vary from engine to engine, so make sure you have the right set!
Tying into the first point, oil and fuel filter replacement is a scheduled and routine type of maintenance, but a vital one for engine health. Specialized tools for removing the caps and filters are a better alternative than trying to remove them by hand.
The internal piping of a turbofan engine can be extremely complex and disassembling it for visual inspection is expensive in both man-hours and money. A borescope and a set of guide tubes to thread through the engine’s ports can help you save both. If you operate a mixed fleet with different engines however, you’ll need guide tubes matching each of the various engines.
Helical inserts, or helicoils, are used to secure steel screws inside magnesium or aluminum housing. However, these screws can sometimes get stuck inside their inserts due to heat distress or corrosion, meaning that if you try to remove the screw during disassembly, the insert will be removed as well. Whenever this happens, you’ll want an insert tool kit to replace the helicoil. Helical inserts are also used in other parts of an aircraft’s fuselage, so an insert kit is useful in other maintenance applications as well.
In a turbofan engine, the seals of the accessory gearbox can eventually begin to leak. This applies to both the carbon-face seals used in newer models as well as the older neoprene seals and can be identified by oil stains in the bottom of the engine’s cowling. These stains are easy to spot during a visual inspection, and easily fixed as long as you follow the engine’s maintenance manual and use the proper tools.
If an aircraft with bladed fans is left outside without engine covers, windmilling can occur. Windmilling is the issue of the engine’s fan turning while the engine is shut down, which causes a slight degree of friction as the blades shift in their pockets. In cold-weather conditions, shrinkage between components can make this friction an even greater issue, and eventually produces titanium dust that can become a serious engine health issue. Therefore, fan blades need to be removed one by one, have lubricating grease applied to them, and then re-installed. Each step in this process requires specialized tools for the job.