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Home> Maintaining your Continental  and Lycoming engine

Good Shop Practices when handling Engine Parts

•  When taking apart an engine never throw away any old parts until you re-assemble the engine.
• All parting surfaces (such as crankcase surfaces) are to be placed face up to protect the parting surface from nicks or scratches
• Never pile any parts on top of parting surfaces.
• High strength steel parts are to be protected from nicks. Never pile connecting rods on top of one another. 
• All metal-on-metal wear parts are to be identified so they go back together in the same location. For example, push rods and rocker arms, cam followers and camshaft. OK I know that very few  mechanics preserve the location of the push rods to the rocker arms but its still not a bad practice.
• Never use a punch, etc, or electric pencil on engine parts.
• Never use metallic objects such as a screwdriver to separate crankcase halves.
• Corrosion pitting is not allowed on high strength steel parts

Cross-section of Lycoming cylinder barrel showing cooling fins machined into barrel. There should not be any corrosion pitting on the outside of the cylinder barrel. Barrel surface is Channel Chrome.

an early shop experience: When we received engines into our shop that were disassembled by someone else I would inspect the crankcase to make sure that the mechanic hadn't  tried to pry apart the crankcase thereby gouging the surfaces. Once the parting surfaces are gouged then the crankcase must be sent out for resurfacing and line boring, a expensive repair.

One day  the FBO next door brought over an engine with a gouged crankcase.  I called the service manager and explained what I had. He walked over to our shop, looked at the gouge and left down the street in his car. When he returned I asked him where he had gone.

His said the mechanic who gouged the crankcase could not be blamed for something that he hadn't learned in A&P school. He had gone to the school and blamed the instructor for the mechanic's lack of basic knowledge of engine practices.

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