6BT maxing out at 2000 rpm's

[daniel girard]

I just purchased a 1989 Blue Seas 31 with a 6BT Cummins, 20 x 16 prop (original spec prop), 1950 hours on engine. With full water tanks and fuel tanks (260 gallons total) and three people on board I am maxing out at 2000 RPM’s at 10 knots. Engine runs great, boat yard mechanic told me I need to have prop mapped and drop to a 14″ pitch to reach 2650 rpm’s. Any thoughts?
Thanks

Topic

[daniel girard]

Thank You, I will go through the low power troubleshooting list.
Throttle linkage does hit the stop, before my 8 hour shake down cruise the racor 500 filter was changed (filter was plugged up) and bowl was cleaned of mud like material, the spin on filter has not been changed yet. The racor did not plug up during the 8 hour trip and no mud in bowl. There is no black smoke just a hint of white smoke.

[daniel girard]

210 HP, serial #44250588, no black smoke.

[Corey Schmidt]

Have you gone through ALL of the steps outlined in the following article before doing anything?

https://www.sbmar.com/featured-article/understanding-low-power-troubleshooting/

[Rob Schepis]

Is this the 2,600rpm 220B engine ?
Serial number?
That’s quite a shortage of rpm’s …. Any black smoke?

[Author]

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