Tag: diesel sailboat engines

Motorsailing and the tachometer reads zero.

Motorsailing and the tachometer reads zero.

The first cruise we took on Makani was from Sausalito to Benicia.  The Sausalito Yacht Club sponsored the cruise for members so they arranged for slips in Benicia and dinner at the Benicia Yacht Club.  Normally, it’s a nice 3 to 4 hour downwind sail north through San Pablo Bay.

Of course, the wind disappeared and we ended up motorsailing the entire way.  After going for about two hours at around 2500 rpm our tachometer dropped to zero.  Not having any idea what to do, I shut down the diesel and ghosted along under sail.  Eventually we approached the Carquinez Bridge which is around a dogleg to starboard.  With the wind almost nonexistent and a lot of commercial shipping in the area, we decided to fire up the diesel. Started right up and the tach was reading perfectly.

We returned to Sausalito on Sunday, again having to motorsail all the back, because now the wind was right on our nose at 20-25 knots.  Again after about two hours of motorsailing the tach dropped to zero, but this time we ignored it and continued home without incident.

Monday, I spoke to Hans List at List Marine and he explained the situation.  On the Westerbeke, and other makes, the tachometer is run through the alternator.  When running for a few hours the batteries were completely topped off, which caused the tachometer to read “zero.”  We could have ignored it, or turned on some equipment that would have put a drain on the battery which would create charging and the tachometer reading in a normal fashion.

Interesting explanation, but not one I would have expected.

 

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The Engine in Makani, Nonsuch 30U #278

The Engine in Makani, Nonsuch 30U #278

Makani was built in 1985 and is powered with a Westerbeke 27 of the same year.  As noted earlier, the engine was surveyed prior to purchase and the previous owner did a good job of maintaining the power plant.

We had a punch list of items to take care of based on the survey and my own wish to try and stay ahead of any maintenance issues.  The boat was brought to List Marine in Sausalito where Hans List and his crew took care of everything.  Besides replacing hoses, belts, and filters, we also replaced the Exhaust Elbowa and manifold gaskets.  This should be done every 3-5 years and there was no record when it was done last.  Hans also recommended that the engine feb repainted with primer and corrosion resistant paint, which was done.  The result is an engine that looks as good as new.

In the Nonsuch 30U the engine has a V-Drive so it is actually mounted “backwards.”  But there is plenty of room to get to all the sides of the engine either from the cabin or through the cockpit lazarettes. Even me at  6′ and 220 lb can get down there!