Knock knock

[jimma4191]

On my 1987 Pearson 33-2 Sailing today. Four to six foot seas on the starboard quarter. Lots of steering and playing the helm. I would surf and need to fight the bow down. As soon as I released the load on the helm and turn back to starboard I would get a knock from under the boat. Initially I thought it was something rolling around somewhere but now realize it is perfectly synced with this action and seemingly this one point of sail and conditions. I recently did a routine inspection on the quadrant and cables. Nothing to see there. I now have rudder worries. I just launched a week ago and in the previous week did a simple lift test on the rudder. Nice and tight with no noticeable movement. Any thoughts would be greatly appreciated. Thanks, Jim

 

[Kings Gambit]

On my 1987 Pearson 33-2 Sailing today. Four to six foot seas on the starboard quarter. Lots of steering and playing the helm. I would surf and need to fight the bow down. As soon as I released the load on the helm and turn back to starboard I would get a knock from under the boat. Initially I thought it was something rolling around somewhere but now realize it is perfectly synced with this action and seemingly this one point of sail and conditions. I recently did a routine inspection on the quadrant and cables. Nothing to see there. I now have rudder worries. I just launched a week ago and in the previous week did a simple lift test on the rudder. Nice and tight with no noticeable movement. Any thoughts would be greatly appreciated. Thanks, Jim

I owned and sailed a Pearson 30 converted to wheel steering for 8 yr. It had an intermittent tendency for the rudder post to make knocking sounds on certain points of sail or in certain conditions. I think I remember reading an article about this knocking, but I don't remember much of the details except, however, that it was a design issue that did not affect the sailing of the boat. That might have something to do with yours as well.

Addendum: From Practical Sailor on the P-30
"The Pearson 30’s spade rudder has provided the only recurrent problem with the boat. The rudder stock consists of a thick-walled stainless steel pipe. The stock enters the hull through a slightly larger diameter fiberglass rudder tube, which projects above the waterline to the cockpit sole, eliminating the need for a stuffing box. The rudder stock rides in two Delrin bushings, one at the top and one at the bottom of the fiberglass rudder tube. Wear in these Delrin bushings causes play to develop in the rudder stock."

https://www.practical-sailor.com/reviews/boatreview/pearson_30-1224-1.html

 

[Will Gilmore]

Is this a centerboarder?

-Will (Dragonfly)

 

[kloudie1]

Loose engine mount?

 

[jimma4191]

5'11" fin keel spade rudder hull number 109. We've owned the boat eighteen years. Pretty much annual inspection of the steering. Cables are tight. Did a lift test on the rudder a couple weeks ago and it was tight and unchanged. Is this how I would detect a noticeable bushing wear problem?

 

[jimma4191]

Had the engine serviced a couple weeks ago also. He did not make note of any engine mount problem.

 

[NYSail]

You are in tune with your boat and will know when she needs help

Greg