Hunter 340 Rudder Challenge

[alitaptap]

A friend asked me to check over his Hunter 340 (1998 model), on the hard, while he is restricted from travel (hopefully not for much longer). I noticed what appears to be a delamination near the top of the trailing edge of the rudder – see photograph.

I have searched for known problems of this type on a Hunter 340 and I have searched the Internet for definitive information about the actual construction of the Hunter 340 rudder but to no avail.

If the rudder is hollow or filled with something like styro or balsa (as many are) then the hole would appear to allow ingress and eventual inundation of the rudder – not good . . . had this happen on a yacht 20 years ago and the rudder eventually failed because the internal metal formers finally corroded and broke free from the shaft.

If, on the other hand, the rudder is in fact solid then the apparent delamination evident can be fixed very easily.

Does anyone have actual knowledge of the construction of the Hunter 340 rudder or have experience of fixing a similar challenge on a Hunter 340?


Or, is this something that can be filled, faired and forgotten? . . . if "yes" please explain why . . .

[Tetepare]

Common problem in the freeze zone. Rudders are foam cored. Water gets in, freezes. Shells get pushed out, delaminate, crack. They can separate from the internal frame. Even without freezing, saltwater ingress can rust the frame.

Various solutions exist and have been covered in this forum. Our new to us boat has a similar problem. After haul out I drilled holes to drain the rudder. In spring I’ll foam fill while compressing the rudder to shape. Then repair the shell.

Ours is a freshwater boat. That you show appears to be salt, so I’d have concern about the frame. Yours looks pretty bad, and the foam may no longer bonded to the foam, allowing independent movement and further damage/ separation. I think it probably needs to be split for review and repair, or totally replaced.

[alitaptap]

Thanks Tetepare for the feedback.



In this instance freezing is not an issue as the yacht has spent the last 20 years in the Philippines (where it currently resides), water never below 19degC and air-temp never below 24degC, but I think we should drill a couple of holes close to the bottom of the rudder to see if there is water already in there, thanks for that suggestion. I guess what happens after that depends on what comes out of the hole(s) we drill.


Still trying to confirm the actual material(s) of the rudder construction . . .

[Jim Cate]

Still trying to confirm the actual material(s) of the rudder construction . . .

Have you contacted Hunter directly yet? Seems that they will know!

Jim

[Tetepare]

Like most production boats of the period, it's metal frame, foam core, and fiberglass.

There's a trick I use, kinda like voodoo, called "search engine". This one took me to the Hunter Owner's Group and has a nice image of H340 rudder construction. https://shop.hunterowners.com/hp/par...40&c=3&p=55546

[alitaptap]

Jim, yes I have emailed Marlow-Hunter but my requests have probably fallen into either, the "too old" or, "too difficult" box because no response.


Tetepare, the item in the link you kindly found is for a replacement rudder (correct?) but the drawing suggests a different internal design to the original and with the possibility of a different construction. The original design (apparently) is shown in this drawing from Marlow-Hunter website: https://www.marlow-hunter.com/wp-con...0-%20Shaft.pdf

[Stu Jackson]

There is a very active Hunter group here:
https://sbo.sailboatowners.com/recent-fx.php


Try them, too.


Good luck, all the best

[alitaptap]

Originally Posted by Stu Jackson

There is a very active Hunter group here:
https://sbo.sailboatowners.com/recent-fx.php


Try them, too.


Good luck, all the best

Thanks Stu, I signed up, awaiting reply from their Administrator

[Spot]

Foss Foam Products website:

https://www.newrudders.com/standard-...t-replacement/

Being in PHL you may want to look over there instead of in the US.