Is this normal for a thruhull?

[jeanathon]

I pulled this boat out of the water after buying, and it has since been languishing in my yard. Today while thinking about upgrading transducers and such I pulled the knot meter thruhull out very easily with my hand without unscrewing anything. Surprised the water pressure had not previously pushed it into the boat out of the thruhull. See attached pics and let me know if this is normal..
Thanks.

[senormechanico]

There is supposed to be a stainless steel pin which holds it in place.

[Boatyarddog]

Originally Posted by senormechanico

There is supposed to be a stainless steel pin which holds it in place.

There should also be a blank plug, to place in the hole when the knot meter or transducer is removed for maintenance, be sure to add a lanyard to this plug so it cannot drop into an inconvenient area when it's most needed.


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[jeanathon]

Originally Posted by senormechanico

There is supposed to be a stainless steel pin which holds it in place.

Thank you. I noticed the hole for the pin when I posted the pictures. But not while working on it.

[Rainh2o2]

I was able to just slightly twist and pull out 2 thru hulls on my boat when I first got it but that's normal for an old catalina with original thru hulls, they didn't install them very good. I ended up just removing all of them. I don't see the need for them in a small boat like mine.

[landonshaw]

I have completely removed the knot meter. It always gets fouled here in the Caribbean and becomes another thing to maintain. I use my electronic navigation to tell me how fast we are going. We don't race and normally cruise for at least 12 hours. So very precise reading are not a necessity.


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[reed1v]

Suggest you fill in that hole and go with a transducer that glues down to the inside of the hull so you have one less hole in the hull. Those old impeller types have been known to let go and fill boats with water. Used on a lot of cheaply build boats(Cal, Ranger, Columbia, and so forth) back in the 70s-80s.

[jeanathon]

Some good food for thought! And sorry I wasn't very clear with my first post. It's not the actual thruhull, but rather the wheel thingy. and of course not a transducer.

[Dody]

The thing is you've got to be able to remove and clean it when it's fouled - while the boat is still in the water. So, yes, it should come out without Problems. But, of course, not on its own! All these wheelie-speedos are meant to have some kind of safety-equipment so they don't just pop out - a pin, a lid with a thread or or or.

[Djarraluda]

Whilst the actual transducers are typically a standardised product from another manufacturer, it looks very similar to mine, which was with an Autohelm ST30.
Yes, I have the pin and the blanking plug, but when I purchase the boat, the battery in the adjacent locker had been gassing, so there were some acrid fumes present. I then discovered that the aluminium backing ring holding the transducer housing into the hull had corroded away. I used a ring of epoxy putty to secure it.
As far as the actual paddle wheel and plug are concerned, there are 2 separate O rings on the stem, keep them lubricated with silicone grease and it all works well.
I remove the paddle wheel every time I leave the boat - never get any fouling.
Roger