I have a CD28 with a Universal M3-20 diesel.
The manual says cruising RPM are 2600 to 3300.
I have a 2 blade 13x8 propellor. Now for some
observations...
(Don't take the absolute value of the knots too
seriously, there was a current against me)
RPM KNOTS SOUND
2000 3.5 Like a sewing machine
2500 4.0 Like a tractor (diesel clack-clack)
2800 4.3 Slight booming sound in deck.
3000 4.5 Very noisy and vibration felt in cockpit seats.
What to do?
a) I would like to motor at 2000 especially if I am
also using the sails. Will this harm the engine?
b) I usually motor at 2500 because the noise isn't too
bad but this is below the recommended range. Is this bad?
c) 3300 is quite unpleasant but faster. Is it safe?
Mike
CD28 "Haven"
tmike@ma.ultranet.com
Excessive viabration?
Moderator: Jim Walsh