Boat repower services. Engine swaps, repowering, and full power-train replacement for outboards and inboards.
Repower is the right answer when the cost to keep repairing the existing engine exceeds the value it adds back to the boat. Common triggers: a major lower-unit failure on a 15-year-old outboard, a cracked block from skipped winterization, compression loss across multiple cylinders, or simply an engine that has reached the end of its useful life on a hull that still has many years left in it.
At Atlantic Boat Repair we repower outboards (two-stroke and four-stroke from Mercury, Yamaha, Honda, Evinrude, and Tohatsu), inboards, and I/O drives. The scope of a repower goes well beyond the engine itself. We evaluate the transom condition for the weight and torque of the new engine, the existing fuel and electrical systems, the controls and rigging compatibility, and propeller selection for the new horsepower curve.
Repowering is a major decision and the wrong choice locks in a five-to-ten-year mistake. Too little horsepower means the boat will not plane with a full load. Too much horsepower stresses the transom, exceeds the design rating of the hull, and can void boat insurance. Brand mismatch with existing controls means costly rigging changes that the original estimate did not anticipate. We help you pick the right replacement engine by working back from how you actually use the boat: cruising, fishing, family bay use, or wakesports.
A typical repower in Plymouth runs three to six weeks once the engine arrives. The bulk of the time is rigging: new harnesses, new gauges where needed, throttle and shift linkage, propeller install, fuel hose replacement, anode setup. We do a sea trial after install to verify performance under load, RPM at wide-open throttle, idle stability, and steering response. Boats that come out of a properly executed repower often perform better than they did when new, because everything around the engine has been refreshed at the same time.
Our experts diagnose and resolve any issue.
Water in gear oil, gear damage, or shaft failure on an older engine where rebuild cost exceeds replacement value.
Usually from skipped winterization. Almost always a total loss for the engine.
Worn rings, scored cylinder walls, or head gasket failures on engines past the rebuild horizon.
Hull is in good shape, engine is at the end of its life. Repower is often more cost-effective than buying a new boat.
Older outboards from brands that no longer make parts. Repowering avoids escalating repair costs.
I have nothing but good things to say about Atlantic Boat Repairs. Ron and Ryan have been reliable and affordable for years. They always answer the phone, and provide exceptionally fast turnaround even with last minute service requests. Repowered my boat with twin 150 tohatsus 4 season ago (650 hours) and absolutely love them. Thanks guys- you are the best.
peter lyons
Verified Google ReviewMarshfield
Ron and Ryan were fantastic to work with. Customer service and attention to detail made repowering my boat a great experience. Would recommend Atlantic to anyone looking for a repower or outboard work.
Christopher Yuknis
Verified Google Review
You can’t find a better boat repair shop on the east coast! They repowered my boat 2 years ago! And have stood by me through all oil changes upper and lower unit. Any small problems have been addressed immediately! And the friendly service of Ron and his head mechanic Ryan has been phenomenal! Don’t hesitate to bring your boat to Atlantic! For the best customer service you will ever experience! Ron has 50 years of knowledge and experience and can deliver satisfaction! As well as Ryan! A hell of a mechanic!
Brian Donahue
Verified Google Review
I recently had to upgrade my older outboards to something a little newer and with more horsepower. Ron and Ryan were extremely helpful when I was looking for engines, and when I did find a pair of 250's, they took delivery of them, removed my old engines and had the new ones installed in no time. We also worked through some electronics upgrades as well. They had some great suggestions and I'm extremely happy with the end result. The communication through the whole process was outstanding, they would always provide updates and expected completion date. This all occurred during one of their busiest times of the year. Can't say enough good things about the team at Atlantic!
Joe Craig
Verified Google Review
Great shop - highly recommend to anyone looking for a good boat service shop without the marina prices. Ron and Ryan repowered my boat with a tohatsu 250 and did a phenomenal job. Got it done in less than 2 weeks to get me back on the water
Chris Romano
Verified Google Review
Recently had to have our engine replaced- Ryan and the crew had a total engine replacement down in less than a week- and went over and above connecting all the new systems, removing the old stuff and have followed up numerous times during the engine break in period. Highly recommended Atlantic boat They have services our boats for years always with great results
Siobhan Perenick
Verified Google Review
Explore our other boat repair services.
Jul 9, 2026 · 7 min read
A boat repower is more than swapping out an old motor. Modern outboards open the door to updated controls, digital gauges, integrated steering, and a helm that actually matches how you want to use your boat.
Read article
Jun 30, 2026 · 8 min read
Still love your boat but dreading every start? Learn the clear signs it's time for a boat repower, how repowering compares to continued repairs, and what the process actually involves.
Read articleCommon questions about our boat repower services.
Two factors: the cost of repair as a percentage of the engine value, and the age and condition of the engine. If a major repair would cost more than half the price of a new engine, and the engine is more than 10 years old, repower is usually the right call. We will give you both estimates so you can compare directly.
Sometimes. If the new engine is the same brand and series as the old one, controls and gauges often carry over. Switching brands almost always means new harnesses and gauges. We will tell you up front what is reusable and what is not so the estimate reflects the real scope.
Three to six weeks once the engine is in hand. The waiting time for the engine itself is variable: same-day on common SKUs, several weeks on less common configurations or during peak spring demand. We coordinate the timing so the boat is not sitting in pieces for longer than needed.
Often yes, within limits. The hull has a maximum horsepower rating that we will not exceed, both for safety and for insurance reasons. We will pull the rating and let you know what range is in bounds. Going to the top of the range adds top-end performance; staying mid-range adds fuel efficiency and longer engine life.
Mercury, Yamaha, Honda, Evinrude, and Tohatsu on outboards. On inboards and I/O drives, MerCruiser, Volvo Penta, and Crusader are the most common. We can source other brands by request but lead times and parts availability vary.
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