I would just like to thank you for your advice on changing my prop to obtain the correct WOT. Last week the boat was put back in the water with the newly adjusted propeller (2″ of pitch removed) and the results is astonishing..
With a clean bottom, full fuel tank and deck loaded with 800kg, the boat reached 2600 rpm in poor weather conditions (2 – 3 meter northerly swell with a south east force 5/6 creating a confused sea. Ha, typical weather for us here in the north sea). I am sure that if I waited for the perfect conditions (flat sea with big tides assisting) I would of seen 2700 rpm, but time is money and it is very rare to have such conditions in the north sea during the winter.
During holding the throttle at WOT an indicated speed of 28 knots was observed but still climbing…
Propping of a Cummins 6CTA