T&T: Running high horsepower engines at low speed

[Allen Ames]

I have 200 HP turbo-diesel (Volvo TAMD41) in a Camano 28/Troll/31.  We spend
a lot of time on anchor and charge the batteries for a couple of hours a day
with the engine at high idle (1500 RPM).  The boat will do 13 knots at 3300
RPM, but we are on a 7 knot (at 2000 RPM) budget.

 

I have spoken to at least 3 different Volvo certified mechanics and a
multitude of other "experts" and have gotten more opinions than the number
of people I spoke to.

 

ALL of them said the best thing was to run her at 10 - 20% below maximum RPM
all the time.  When I said that this was impossible, the opinions varied:

1.	It's probably ok and you shouldn't worry about it.
2.	Whenever possible, particularly after a long period at anchor, run
her up to speed for about an hour.
3.	Whenever running, run her up to speed for a few minutes every hour
or so.
4.	Whenever running, finish your day's run with an hour at speed -
taking time to cool her down as well.

 

So far, we don't seem to have any problems and we've taken her from
Connecticut to Key West and back doing a combination of #2 and #4.  We're on
our way south again as I write this.  What to do?

 

Allen and Judy Ames

SESAME

blog:  <http://camano130.blogspot.com/> http://camano130.blogspot.com/

photos:  <http://community.webshots.com/user/allen_ames/>
http://community.webshots.com/user/allen_ames/