CD28 flybridge, Normal operating RPM, Diesel

Tony Raymond · Post by **Tony Raymond** » Apr 17th, '98, 11:00

I have a 1988 CD28 flybridge w/ the Volvo TAMD41A, 200 hp diesel. I have owned the boat for 3 1/2 yrs. It has a four blade propeller, can't remember the pitch off hand. The previous owner said the CD factory recommended it to him.

Anyway, this is my first diesel boat so I've done a lot of reading and asking questions. The one I can't get a good answer to is:

What is Normal or Sustained running rpm for the Volvo TAMD41 set up for light/pleasure duty?

The volvo manual specifies WOT at 3600 -- 3900 rpm and nothing about normal operation. My engine/prop setup max's at 3800 rpm. I have read and been told various things about Normal operation , such as:

300 rpm below WOT = 3500 rpm

10% below WOT = 3420 rpm

12.5% (1/8 of max) below WOT = 3325 rpm

25% below WOT = 2850 rpm

Your thoughts and comments would be appreciated.

Thanks
Tony

tonyraymond@digital.com