JobsMercury Marine

Principal Engineer - Mechanical Development

Mercury Marine · Fond du Lac, WI

Posted Jul 26, 2026 · We last checked this listing on Sep 20, 2026

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Likely interview questions for this role

Written from this job description, not a generic list. Each one notes what the interviewer is really checking.

Behavioral

Walk me through an engine system you owned from concept to production. What was the system, and what decisions were really yours to make?

whether the candidate has genuine end-to-end ownership experience versus supporting role

Tell me about a time you had to trade off performance, durability, NVH, weight, and cost on the same component. How did you decide what won?

ability to make system-level tradeoff calls, not just optimize one dimension

Tell me about a legacy design or long-standing approach you challenged. What pushback did you get and how did you make your case?

willingness and skill in overturning institutional habits with evidence, not ego

Tell me about a patentable idea or genuinely novel solution you generated. What made it new, and did it actually make it to production?

innovation track record and whether ideas survive contact with real constraints

How have you mentored a more junior engineer through a technical problem you knew the answer to, without just handing them the answer?

teaching and leadership style versus doing the work themselves

Technical

Say you're picking bore-stroke ratio and valvetrain type for a new spark-ignited engine architecture. What factors are you weighing and in what order?

depth of architecture-level engine knowledge versus component-level familiarity

Describe a DFMEA you built for an engine component or system. What failure modes did you almost miss, and how did you catch them?

rigor and honesty in risk analysis rather than a check-the-box process

Tell me about a Design Validation Plan you wrote and executed. What testing did it call for, and how did the results change the design?

whether the candidate closes the loop between test data and design decisions

What manufacturing process, whether casting, forging, machining, or heat treatment, has burned you before by looking fine on paper but failing in production? What did you learn?

real hands-on manufacturing knowledge versus textbook familiarity

What's your experience with turbocharged or supercharged spark-ignited engines versus naturally aspirated, and where do the development challenges really differ?

breadth across engine architectures, since the role spans all three types

Situational

You find that a supplier's component design doesn't meet the system requirement you set, but the supplier insists their part passes their own spec. How do you handle it?

how they manage cross-functional and supplier conflict without just pulling rank

A root-cause investigation on an engine failure crosses three component boundaries and three different engineers' territory. How do you run that investigation so it actually converges on an answer?

cross-functional leadership on ambiguous, politically sensitive technical problems

You've got limited budget for testing and three concepts you think could reduce technical risk on a new valvetrain. How do you design a cost-effective experiment to narrow it down?

resourcefulness in test design and prioritization under budget constraints

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The full job description

As published by Mercury Marine.

Are you ready for what’s next?   Come explore opportunities within Brunswick, a global marine leader committed to challenging conventions and innovating next-generation technologies that transform experiences on the water and beyond.  Brunswick believes “Next Never Rests™,” and we offer a variety of exciting careers and growth opportunities within united teams defining the future of marine recreation.  Innovation is the heart of Brunswick. See how your contributions will help transform vision into reality. Position Overview: As a Mechanical Development Principal Engineer, you will serve as a senior technical authority within Mercury’s product development organization. This role combines direct ownership of assigned engine systems with a broader responsibility to provide system-level guidance and technical judgment across all engine development.  At Brunswick, we have passion for our work and a distinct ability to deliver. Essential Functions: • Develop engine systems (valvetrain, pistons, connecting rods, balance systems, bearings, etc.) from concept selection to production. • Advise in developing new engine architecture for naturally aspirated, super charged, or turbo charged spark ignited engines • Provide guidance on system layout and component selection (bore-stroke, layout, valve train type, piston sizing, crank train layout, timing drive) • Work with component engineers, suppliers, and the analysis group to verify component designs meet system requirements. • Develop component & system level DFMEAs and Design Validation Plans (DVPs). Then, using the test plan identified, execute the required testing and document results. • Design cost-effective experiments to prove proposed concepts and reduce technical risk. • Challenge legacy solutions and introduce innovative, manufacturable designs. • Generate patentable ideas leading to commercial success. • Provide engineering recommendations on system-level tradeoffs involving performance, durability, NVH, weight, cost, and manufacturability. • Participate in design reviews, issue resolution, and root-cause investigations crossing component boundaries. • Mentor and technically guide team members. • Help define and reinforce engine development best practices and internal technical standards. Diversity of thought and experiences is fundamental when imagining the unimaginable. Certain skillsets/experiences are necessary; however, others can be developed along the way. Required Qualifications: • Bachelor’s degree in Mechanical Engineering or equivalent. • 8+ years of progressive experience in internal combustion engines. • Demonstrated ownership of engine component or mechanical systems development. • Broad understanding of overall engine system interactions. • Proven ability to define and execute comprehensive DVPs. Preferred Qualifications: • Master’s degree in Mechanical Engineering or related field. • Proficiency with Creo / ProE. • Experience applying DFSS tools. • Recognized technical leader within prior organizations. • Strong understanding of engine related manufacturing processes including casting, forging, machining, injection molding, heat treatment, grinding, balancing, and assembly. The hiring range for this position is $103,200 - $164,500 annually. The actual base pay offered will vary based on multiple factors including job-related knowledge/skills, relevant experience, business needs, and geographic location. Compensation decisions are dependent upon the specifics of the candidate’s qualifications and the business context. In addition to base pay, this position is eligible for an annual discretionary bonus. This position is eligible to participate in Brunswick's comprehensive and high-quality benefits offerings, including medical, dental, vision, paid vacation, 401k (up to 4% match), Health Savings Account (with company contribution), well-being program, product purchase discounts and much more. Details about our benefits can be found here . Next is Now!   We value growth and development, recognizing that people come with a wealth of experience and talent beyond just the technical requirements of a job. If your experience is close to what you see listed here, please still consider applying. Brunswick is an Equal Opportunity Employer and considers all qualified applicants for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, protected veteran status or any other characteristic protected by federal, state, or local law.  Diversity of experience and skills combined with passion is key to innovation and inspiration and we encourage individuals from all backgrounds to apply.  If you require accommodation during the application or interview process, please contact hrsharedservices@brunswick.com  for support.  For more information about EEO laws, - click here Brunswick Corporation participates in E-Verify as part of our commitment to a lawful and transparent hiring process. For additional information click here: https://www.brunswick.com/e-verify . Brunswick and Workday Privacy Policies Brunswick does not accept applications, inquiries or solicitations from unapproved staffing agencies or vendors. For help, please contact our support team at: hrsharedservices@brunswick.com or 866-278-6942. All job offers will come to you via the candidate portal you create when applying through a posted position through https:///www.brunswick.com/careers .  If you are ever unsure about what is being required of you during the application process or its source, please contact HR Shared Services at 866-278-6942 or HRSharedServices@brunswick.com . #Brunswick Corporation - Mercury Marine

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