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Snafu
 
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Default Cutlass bearing/ shaft bearing noise

I think you are referring to the stern bearing. That's where the shaft
passes through the hull. The cutlass bearing is in the strut just ahead of
the prop, and is more commonly found on a power boat than a sail boat.

In my opinion, the compression nut should be tightened just enough to allow
a tiny bit of water to seep in when the shaft is turning (and maybe allow a
few drips per minute when the shaft is not turning). This water lubricates
the bearing. I think the fact that the rubber squeaks when you turn the
shaft by hand is not a good sign. I hope the bearing has not overheated and
been damaged.

Dan

"Les" wrote in message
om...
My friends are having the following problem with noise in their
cutlass (cutless?) bearing:


"After sitting idle in a marina in Turkey for 9 months, upon leaving,
I have this squeal coming out of my shaft/cutlass bearing below 1600
rpm. It peaks in loudness and resonates at 1300 rpm. It stops above
1600 rpm. It does not occur in reverse. I thought it may be coral
growth from sitting still for a long period of time. However, it is
still there after 60 miles of motoring.
The shaft is 1 1/4 " about 32 " long. The stern tube is approx 17"
with the packing gland on one end and bearing mounted at the other.
The boat is a 38' full keel sailboat with an outboard rudder and a 40
hp motor.
The bearing was installed and engine aligned 2 years ago in Trinidad
and logged 500 hrs with no problems. Since then no adjustments have
been made to that installation. Hauling the boat last spring showed
the bearing to still be in good tolerance. I have eliminated all other
possible sources for the noise including the packing gland. There is
no vibration. When I turn the prop manually I can hear a rubber squeak
coming from the bearing/shaft surfaces."

Does anyone have any idea of what the cause of this may be?