Marine Diesel Repair, Diagnostics, Overhaul, Maintenance and Performance

in the Florida Keys

Marine Diesel Specialists

Marine Diesel Repair

Marine Diesel Maintenance

Marine Diesel Rebuilding

Diesel Mariner Performance


Complete Marine Diesel Services for Repair, Maintenance, & Performance in the Florida Keys

Marine Diesel Engine Services

Electrical, Cooling & Fuel Services

Turbocharger Rebuilding

24/7 Emergency Services

Mobile Marine Service - We Come to You!

Several white yachts docked in a calm marina during the day, with trees visible in the background.

Marine Diesel Repair

& Diagnostics

Trust us for complete diagnostics and repair for any diesel marine engine.

A sleek, teal and white luxury yacht docked in a marina under a bright blue sky.

Marine Diesel

Overhaul

Our factory trained techs will restore your marine engine’s performance

A white luxury motor yacht cruising at speed through blue ocean water under a clear sky.

Marine Diesel Maintenance

& Performance

Get more life and power from your engine with our expert services.

Florida Keys Marine Diesel

Why Boaters Across the Florida Keys Choose Florida Keys Marine Diesel

Since 2017, locally owned Florida Keys Marine Diesel LLC has been providing expert marine diesel engine repair, maintenance and rebuilding for vessels throughout the Florida Keys.

A high-angle view of a white, industrial marine diesel engine featuring large, textured dark carbon fiber air intakes.
An aerial view of a large white yacht anchored in clear, turquoise tropical waters with several smaller boats nearby.

Experienced, Factory-Trained Marine Diesel Technicians You Can Trust


With more than two decades of combined experience among our factory trained technicians, our team is equipped to handle any problem your boat may be experiencing. Whether it’s time for routine marine diesel maintenance or a complete marine diesel engine rebuild, you can rely on us to deliver exceptional results. As a mobile marine mechanic in the Florida Keys, we make it easy to care for your vessel, no matter what engine it’s running. We are an authorized sales and service dealer for MAN Marine Diesel engines, and also cater to MTU, CAT, Mercury, MerCruiser, Volvo Penta, ZF, Yamaha, Evinrude, Suzuki, Honda and others as well. To learn more, or to request an appointment for diesel marine service in the Florida Keys, please don’t hesitate to give us a call.

Serving the Florida Keys & Surrounding Areas


Key Largo Islamorada Marathon Key West MiamI

As a local marine diesel business, the crew at Florida Keys Marine Diesel takes pride in servicing personal and commercial vessels docked or stored in Key Largo, Islamorada, Marathon, Miami and throughout the region. To ensure we are able to provide the best diesel marine engine services in the Florida Keys, we invest in ongoing training and modern equipment. This includes computer diagnostic tools that allow us to service, repair and improve performance of all types of engines. If you are encountering any signs of engine trouble, or if it is time for marine diesel maintenance in the Florida Keys, don’t hesitate to give us a call at 786-475-8533. The professional boat engine mechanics at Florida Keys Marine Diesel are ready to help you get back on the water.

24/7 Emergency Service


If you’re in immediate need of service, we offer 24/7 diesel marine repair in the Florida Keys. Give us a call for fast service. Whether you’re stranded or prepping for a charter, our team can ensure your vessel is safe and reliable.

Several white yachts anchored in the ocean during a golden sunset.
The silver, metallic logo for MAN, featuring the letters
The MTU company logo: a blue parallelogram containing the white letters
The Caterpillar Inc. logo, featuring bold black letters

Customer Reviews  |   Your business is very appreciated.

G and stars

Mike is an awesome & amazing mechanic, very honest and gets straight to the point!! He’s been serving my 90 ft yacht for a while and no complaints. Truly the best.


- Captain M.

Blog  |   We invite you to monitor our News Blog for informative articles.

A large, white marine engine with twin turbochargers and carbon-fiber air filters, installed in a clean engine room.
By Florida Keys Marine Diesel LLC March 29, 2026
For boat owners throughout the Florida Keys, understanding engine lifespan is key to planning maintenance and avoiding unexpected breakdowns. At Florida Keys Marine Diesel LLC, we regularly help customers in Key Largo, Islamorada, Marathon, Miami and beyond evaluate the condition of their engines and extend their usable life. While every vessel and usage pattern is different, marine diesel engines are known for their durability. When properly maintained, they can run for thousands of hours. Here’s what you need to know. Average Diesel Marine Engine Lifespan On average, a well-maintained marine diesel engine can last anywhere from 5,000 to 8,000 hours before requiring major work such as rebuilding. In some cases, engines that receive consistent maintenance and operate under ideal conditions can exceed 10,000 hours. However, lifespan isn’t just about hours. It also depends on how the engine is used. Long, steady runs at optimal load tend to be easier on engines than frequent short trips, idling, or running under heavy strain. What Impacts Engine Longevity Several factors influence how long your marine diesel engine will last. Regular maintenance, including oil changes, fuel system service, and cooling system care, plays a major role in preventing premature wear. Environmental conditions in the Florida Keys, such as saltwater exposure and humidity, can also accelerate corrosion if systems like anodes and cooling components aren’t properly maintained. Operator habits matter as well. Running an engine too hard, ignoring warning signs, or delaying service can significantly reduce total engine hours. When to Consider Overhaul or Rebuild As engines approach the higher end of their lifespan, signs of wear often become more noticeable. Decreased performance, increased smoke, hard starting, higher oil consumption, and overheating can all indicate it’s time for a closer look. Rather than waiting for a complete failure, many boat owners choose to schedule an overhaul or rebuild once these symptoms appear. Addressing issues early can restore performance and extend engine life well beyond the original hour range. With the right care, a marine diesel engine can provide reliable performance for many years on the water. At Florida Keys Marine Diesel LLC , we provide expert marine diesel maintenance in the Florida Keys to maximize engine life. If you’re unsure how many hours are on your engine or want a professional assessment of its condition, give our team a call at  786-475-8533  and our Florida Keys marine mechanics can help you keep your vessel operating at its best.