I gather that Implementation Engineer is way more natural term, so I would stick to it.
You can judge from the hits coming from a Google search. I brought up some excerpts from sites in the Web.
Job Title: Implementation Engineer
Summary: Implementation Engineers are responsible for customer implementations, that is, installing, integration, upgrading, configuring, troubleshooting and supporting products, and customization of web-based solution suite. And the integration of these products (softwares/systems etc) with others in a dynamic customer environment that may be complex.
"It´s a typical position held by recent graduates generally the job description includes software developing, programming, Web developing, network management, system administration, internet engineers, consultantion. The professional also works as systems consultant, implementation engineer in the Technical department."
-A computer science, engineering, or related Bachelor's degree from a leading 4-year college or university (other majors considered with demonstrated working knowledge of web development)
-1 to 3 years experience in hands-on, web-based application software development preferred
-Excellent written and oral communications skills, listening skills and good technical documentation skills
-Ability to prioritize effectively and handle shifting priorities professionally
-Software/product/solutions implementation experience, preferably in the market environment (a plus)
-Relational database knowledge a plus
-Ability to travel depending on project demands.
-Provides knowledge transfer throughout and at the completion of assigned projects.
-May support other activities as needed.
-Provides updates to case tracking system and or other technical applications for software implementation and Problem
-Stays current on technical specifications and hardware requirements of software products, including new and soon to be released products.
"A Senior Implementation Engineer in the Technical department. Solving and documenting a variety of technical problems both internally and externally relating to Windows NT servers, Exchange servers, IIS & Proxy servers, SMS servers and other systems."