Reconditioned Marine Propulsion Engine or New?
Begin your repower project by learning the relevant State and Federal requirements for marine repowers in your area.
Reconditioned engines work best when they can replace like-for-like engines. This reduces the expense for new accessories such as motor mounts and the electrical panel. Reconditioned engines are often good for 10,000 to 20,000 hours depending on how well they are maintained. Later model recons are very fuel efficient when compared with older engines, especially two-stroke Detroit Diesels. They are simple to maintain and any qualified diesel mechanic can repair them. Factory built four-stroke recon engines will perform like new. They are also roughly 2/3rds the price of new engines, and carry up to one-year unlimited hours warranty.�
New electronic engines, on the other hand, are very fuel efficient, cost more money, and when they need work, they may require an engine dealer who has the computer software to do full diagnostics. New engines will last from 20,000 to 40,000 hours depending on maintenance, and the warranty period for most new marine engines is a full two years or 2000 hours, whichever comes first.
Saving time and dollars begins with an assessment of the running gear. If the boat’s transmission is still good and the propeller shaft is straight, the best and least expensive repower for your boat is as follows:
1-Select a replacement engine near the same power level and rpm as the engine to be replaced. This enables re-use of the same size propeller, keel cooler and exhaust piping. The savings here can easily be tens of thousands of dollars. Pay particular attention to the rear housing and flywheel size so they will mate to the existing transmission. Advertise your old engine before removing it. This gives prospective buyers time to hear it run, and they’ll be willing to pay more if it’s in good shape.
2- Before removing the old engine, get somebody to do an exhaust system back pressure test to learn if the silencer (muffler) is plugged. If it is plugged replace it.
3-Leave the transmission bolted in place.
4-Remove the old engine, clean the area under the engine and paint it white.
5-Clean and pressure test the keel cooler.
6-Replace the front seal on the transmission and the rubber drive blocks (or flex coupling) between the transmission and engine. We also recommend replacing the transmission oil cooler because it’s difficult to be totally certain they are free of debris, even after thorough cleaning.
7-Bolt the replacement engine to the transmission, and make all of the connections.
8-Beside the cost to install the replacement engine, be sure to include these items:
a-$1000 to verify the final alignment on the shaft and engine,
b-$1000 for cleaning up the boat’s DC electrical system, and
c-$1000 for upgrading the old drive belts and hoses in the boat. (Including hoses that run to the hot water heater, if so equipped.)
9-No matter if the replacement engine is new or reconditioned, be sure to have the technician install a fuel system sight glass (MER PN 33448A) between the boat’s Racor fuel filters and the engine fuel system. During the sea trial, they must verify that no air bubbles are entering the engine fuel system with the fuel. If they see air coming in with the fuel (called a suction leak), they must find the suction leak and repair it.
With good planning, your repower will cost far less: Long-term fuel savings will be icing on the cake. Last, of all, let us know how it goes!