Greetings and welcome aboard the CF, George.
As Target noted:
The Volvo-Penta MD17C was sold between the years of 1975 and 1981, featuring 35 horsepower at 2,500 rpm
and a maximum of 2,800 rpm in overspeed mode.
The MD17D model was made from 1981 to 1984 and had a slight increase in performance. This motor
achieves 36 horsepower at 3,000 rpm and is capable of 3,350 rpm.
The workshop manual, for the heavy duty version, indicates both C & D versions were 30 HP @ 2300 RPM (page 39).