Cleaning Your Engine to Lower Operating Cost
By Pratt & Whitney Customer Service
One of the most cost-effective and beneficial ways to maintain your PW100 or PW150 aircraft engine is to wash it regularly, both inside and outside. Consider these important factors to ensure effective washing and optimal engine performance.
1. Contaminants in the Air
The atmosphere is filled with contaminants such as fine particles of dirt, oil, soot and other foreign matter. These contaminates get sucked into engine compressors along with air, especially if you don’t have a filtration system installed. This contamination gradually builds up, forming a coating on the casing, vanes and compressor blades. The buildup reduces aerodynamic efficiency, resulting in deteriorating performance. Sulfidation and other forms of contamination can also corrode engine components.
2. Clean Engines Run Better
It’s amazing what you can accomplish with a little soap and water. Washing your engine has a host of benefits: among others, it improves compressor efficiency, enhances internal turbine temperature margins, lowers fuel consumption, increases the lifespan of hot section parts and reduces corrosion. These benefits improve your engine’s performance and lifecycle, extending the time between overhauls. How often you schedule engine washes depends on your specific fleet and operating conditions, but make sure you perform them regularly to keep your engine performing at its peak.
3. Compressor Washes Are Key
Compressor washes help to minimize corrosion in harsh environments. For such a wash, inject an applicable cleaning fluid into the engine intake using either an installed compressor wash ring or a hand-held wash wand. Regular compressor washes will preserve the health of mechanical components by removing salt, dirt and baked-on deposits that accumulate in the gas path. (For PW100 engines, water could get into the P3 line of the mechanical fuel control system unit, so make sure to disconnect the P3 air pressure sensing tube at the intercompressor case end and put a plastic bag over the end of the tube as recommended in the engine maintenance manual.
4. Other Aircraft Engine Cleaning Washes
External surface washes remove corrosive build-up and ensure the soundness of epoxy coatings on magnesium surfaces.
Turbine washes minimize corrosion in, particularly harsh environments. Use a wash nozzle or modified borescope tube to directly wash high-pressure blades with drinking-quality water. There’s no need to disconnect fuel drains, P3 or handling bleed-off valve lines, while an engine-drying run is optional.
Finally, do a performance recovery wash when there’s noticeable engine performance loss or trend monitoring indicates it’s necessary. Use approved chemical additives to get rid of more stubborn deposits which can’t be removed during normal desalination washes.