Giving New Life to Your Old Boat

By Capt. Parke Brinkley

Oftentimes, half of the value of your boat is in the engines. Boat hulls generally last longer than their engines and after 7-9 years it’s often a practical choice to repower your boat with a new trouble-free and fuel-efficient power plant. Here are a few things to consider when making the repower choice:

OUTBOARD REPOWERING:  Today’s four stroke and direct injection outboards are much cleaner and more fuel efficient than their predecessors. 50% less fuel consumption can mean $875/year in fuel savings for a typical 500 gallon boating season. Repowering an older boat with 4-strokes can result in significant weight increases, so make sure to simulate the weight of the new engine on your transom and check for water entering the scuppers from the outside. One way to do this is to have one or two people sit on the transom with the old motor, and check the water level outside to make sure you’re not creating a hazardous situation by replacing with a heavier motor. The DI motors like the Evinrude E-TEC do not weigh as much as their 4-stroke counterparts, and can be just as efficient. It is possible to switch from I/O to outboard power, with the use of fabricated engine brackets.

I/O (STERNDRIVE) REPOWERING:  New units from your Mercruiser dealer are readily available, as are less expensive ready-to-go rebuilt models from respected companies like Michigan Motorz.

INBOARD REPOWERING:  Gas or diesel? New fuel-injected gasoline boat engines are basically truck and SUV engines, marinized for marine use. If switching from gas to diesel keep in mind that you may need to replace the shafts, struts, and propellers in addition to the engine.  Yanmar is a popular choice for diesel repowers, while companies like Michigan Motorz provide ready-to-go gasoline engine packages.

See the fine engine companies listed below for your best bet on marine repowers.

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