|A 'Nickel Tour' of an Engine Overhaul Shop: 10 Steps the Pros take to get Your Engine Flying High!|
|Written by Floyd Allen|
|Wednesday, 05 June 2013 13:03|
Time flies when you’re flying— err, having fun.” That’s probably best indicated by how quickly the hours pass regarding TBO! When you reach that magical number of 1500 or 1800 or 2000 hours and decide that something needs to be done, you can have the engine rebuilt, over-hauled, or even replaced. While you might have a general idea of what transpires when your engine is being worked on, it’s reassuring to know exactly what happens when you send your engine out. To that end, we contacted Aircraft Engine Specialists (AES) in Chandler, Arizona, for some inside information.
Step 1: Once the engine is received, a work order is cut with all of the directions from the owner included. At this point, any “special requests” are also noted.
Step 2: The engine is disassembled and cleaned. This starts by removing all oil and stripping off all paint. The goal is to get each and every part down to the bare metal. Once this is accomplished the engine moves on to inspection.
Step 3: The inspection consists of both visual and dimensional testing of every part that is to be reused, including a “crack inspection” (see “CSI” sidebar). “It’s during this process that we determine if any machining is necessary for any of the parts,” AES General Manager, Tim Varga explained. Such parts include the crankshaft, crankcase, camshaft, and lifter bodies. If a part needs machining, it’s sent to the appropriate specialty shop for attention.
Step 4: Once the inspection is accomplished a replacement parts list is created. This, of course, includes gaskets, seals, bearings, and internal hardware. Each manufacturer will have bulletins calling out what, exactly, these parts should be.
Step 5: “After we’ve attended to the basics, we turn our attention to the accessories, which will be dealt with as needed,” said Varga. Such “accessories” include the carburetor/ fuel injection system, magneto, and starter. Dependent upon condition, these parts will either be overhauled or replaced.
Step 6: AES next turns their attention to the exterior hardware and bracketry, which are sent out for cadmium plating. Cadmium not only creates a more aesthetically pleasing product, but also provides excellent corrosion protection and doesn’t wear, scrape, or scratch off.
Step 7: Once all of the needed parts (new and/or those that were machined) arrive, each part is cleaned again and painted. The engine is then reassembled.
Step 8: Next, testing ensures that the engine is operating as it should at various settings. Technicians check the oil temperature and pressure, verify that the engine is producing the proper amount of power, and run a compression test to ensure the cylinders are breaking in properly. Depending on whether or not the engine is going to be installed right away, AES then preps the engine for short or long-term preservation.
Step 9: Once testing is completed, the engine undergoes final preparation for shipping. “The client can either pick up the engine themselves, or we can ship it to them,” Varga explained. AES offers free shipping (by truck) anywhere in Arizona. For engines shipped out of state, there is a shipping charge. “If a pilot’s in a hurry to get his engine back,” Varga added, “we have an Engine Exchange program that gets them back in the air immediately.” In this program, a pilot purchases a freshly over-hauled engine and AES ships it out. When it arrives, the pilot pulls out his old engine, installs the newly over-hauled engine, ships the “run-out” engine back to AES, and the process starts over.
Step 10: When the engine is ready to ship, the final paperwork is brought up-to-date and completed, including logbook entries with a list of ADs that were compiled. An 8130 Certificate is then done, the final invoice is filled out, and the project comes to a close.
Whether you opt to send in your engine for an overhaul or take advantage of the AES’ Engine Exchange program, you now have a clear perspective of what happens from the time your engine arrives until it is shipped back to you. To learn more about the AES, visit www.aircraftenginespecialists.com.