Boat Maintenance: Breaking in a New Marine Engine

Do you have a brand-new boat? Maybe a new motor on an old boat? Either way, it’s crucial that you break it in properly whether you keep your boat at home on a trailer, at a marina or at a private boat slip rental. All marine motors, whether inboard or outboard engines, gas or diesel or Mercury, Yamaha or Evinrude – need to be broken in.

You may be tempted to run wide open. Don’t. It’s important to break it in slowly and properly (there will be plenty of time for going fast later). And there’s a specific procedure for doing so. Your owner’s manual will have instructions for this (You have read your owner’s manual, haven’t you?), but we’re going to go over a few of the basic steps.

Failure to properly break in a new motor could result in:

• Mechanical failure
• Reduced life of the motor
• Voiding of the warranty
  
  

The main reason that marine motors need to be broken in is that they’re designed to be run at a constant RPM under heavy loads. It’s a pretty straightforward process and really doesn’t take a lot of time in the whole scheme of things.

Why do you need to break in a marine motor?

• To make sure there aren’t any issues with the motor
• The engine and its internal parts are lubricating each other as grease and oil make their way into all the grooves

Machining grooves are being scrubbed off

Breaking in a Marine Motor

Marine motor life is recorded in hours (rather than miles, like a car). The break-in period for a new boat motor is about 10 hours.

• For the first hour: Run engine under 2,000 RPMs (you can do intermediate bursts one-minute bursts at full throttle every ten minutes or so).
• For the second hour: Keep it under 3,000 RPMs (this will be on a plane, but not at full throttle).
• For next eight hours: Feel free to run at varying speeds, but not for more than five minutes at wide open throttle.
• After ten hours: Run the engine normally.

After 20 hours, bring your boat in for engine service. The fluids will need to be drained from the break-in period due to the fact that parts will have been rubbing against each other for the first time. You’ll want clean fluids, so now’s the time to do it. After this time, have the motor serviced every 100 hours or seasonally.

How long do marine engines last?

A two-stroke or four-stroke outboard engine should last for at least 1,500 hours before needing a major overhaul. Changing oil, flushing the engine and providing routine maintenance can keep it running even longer. Regularly cleaning a marine engine - either at home, at a boat shop or at a private boat dock for rent – is one of the best ways to keep your boat in shipshape … well, shape. Even if you’re running your boat in saltwater, it can last years with proper engine maintenance.

Whether you’re fishing the back country, sightseeing on the local lake or diving and snorkeling in the Bahamas, having a fully functioning and well-maintained marine engine will keep the fun going without interruption. And it’ll get you back to a private boat lift for rent with no problems.

We hope this has helped you with any questions you may have about breaking in a marine motor. As with anything, consult your owner’s manual before leaving a marina, ramp or private boat dock rental with a new marine engine.