I recently purchased a 2001 NT 32 and I noticed during cruising at about 8
knots (1,900 rpm if I recall correctly) a rather distinct and somewhat
annoying low frequency pulsating exhaust sound (noise) coming from the rear
of the boat. I am guessing the frequency is about 5 to 10 Hz. Upon closer
examination, the sound seems to be created or emitted in the rear on the
starboard side of the boat where the exhaust exists the boat. It seems that
the exhaust is somehow interacting with the bolt-on swim platform, causing a
resonance condition. The sound level gets worse as the engine speed
increases. The sound frequency does not seem to change appreciably with
engine speed although I have not confirmed that through actual measurements.
Any attempt to quiet this sound by redirecting/adjusting the water flow
around the swim platform and adding weight to the swim platform by standing
on it, etc. has made no difference.
I am curious if this is normal with this boat model/build year and if anyone
else has been experiencing the same issue. I realize that newer models use
the integrated swim platform. Not sure if the noise issue was a contributor
to the design change.
Hans
NT 32 32175
Columbus, IN