In the spring of 2004, Mercury Marine (Fond du Lac, WI) introduced the Verado a six-cylinder, four-stroke 275-horsepower outboard engine. In addition to being the industry's first supercharged outboard engine, it is noteworthy in terms of its quality assurance program.

Typically, outboard engine manufacturers use end-of-the-line hot testing to verify quality. This involves starting each engine and letting it run for a given period of time after it has been fully assembled. The downside to this kind of testing is that, with a fully assembled engine, it can be difficult to diagnose the root cause of any failure, requiring greater time and effort to make the necessary repair. Hot-test stations also tend to be costly, irrespective of the number of defects that need to be repaired. The cycle time required to complete a test typically results in a production bottleneck.

To eliminate these problems Mercury Marine implemented an in-process testing system from Sciemetric Instruments (Ontario, Canada) to both decrease repair costs and increase throughput; an approach that is standard in the automotive industry.

With any production line, defects can arise at any machining or assembly station, as a result of a damaged sub-component or a problem with one of the assembly machines. The ability to catch a quality issue as soon as it is introduced is important when manufacturing complex products with many production stages.

Mercury Marine's in-process engine testing system includes a number of testing stations located at key points during the manufacturing process where engines can be tested before additional modules are added during assembly. By performing tests before the installation of additional subassemblies, Mercury Marine can more easily diagnose the root cause of a defect and make any necessary repairs. Detecting and addressing a quality issue as soon as it is introduced streamlines the production process and provides for better process control.

Using this approach Mercury Marine is able to verify that each engine satisfies engineering specifications for emissions, power and sound. It has also succeeded in dramatically reducing the number of hot test that it performs.

"The Sciemetric-based test systems that we utilize in our Verado assembly process have been vital in improving first past yield, providing data for continuous improvement opportunities, and validating our processes," says Mercury Test Engineer Aaron Sagmeister. "This results in improved throughput, reduced cost and improved quality."

For more about in-process testing, call 877-581-0112 or visit