GET HOME WITH THE NORDHAVN 47 WING ENGINE

OK! You want a Nordhavn for so many really good reasons. A marriage of a singe engine boat with great range and a back up engine makes a lot of sense. There is one little issue that has been addressed by knowledgable Nordhavn owners and that is back–driving the transmission when underway on the wing engine.

Here’s the problem. Should you lose the main engine and engage the wing, when you move through the water the prop will turn in the slip stream and rotate the transmission. Putting the main in gear, will also cause you to turn the main engine. With the ending in neutral the rotating prop/shaft will turn the transmission on your main engine without the transmission lubricating oil pump working because that pump needs the main engine to be running. Most likely the reason you are running on the wing is that your main engine is down. Long term transmission rotation without lubrication is a really bad idea. Many transmission manufacturers site a time limit. 

I have seen Nordhavn owners who have made arrangements for preventing shaft rotation when running on the wing ending. I am one of those owners. We have tested our procedure and it is really simple. I bought a chain wrench that fits perfectly and closely behind the transmission shaft coupling. I drop it in place with the arm of the wrench laying in a sturdy location and then go ahead on the wing. The wrench bites and can’t be moved, as long as there is energy trying to rotate the shaft. I look forward to demonstrating!