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Water seeping in through Speed sensor through hull

DryLand404

New Member
Is silicone an acceptable patch for the Speed sensor through hull? Water appears to be seeping in through the threads. The plastic ring securing the speed sensor appears to only have a rubber washer between it and the block.
Attached is the over view. It's in the starbird side in the locker floor.
(Finally got the ball of rusted chain out with some careful maneuvering of a chisel and hammer. :) )
 

Attachments

stnick

lee nicholas
The speed sensor( paddle wheel) is suppose to be removed after every outing ! and the plug put in its place. Unless You have a brand new sensor with no wheel ?? !
 

stnick

lee nicholas
Did some one store chain there ? Or were they trying to add weight to the front of the boat ?
 

rolf

Rolf Peterson
It should come out easily so no silicone or other goo required. It could be a bad o-ring, a replacement that was a different manufacturer but old thru-hull". I know, this is not helpful ☺.

Lee, I never heard of changing it out each trip,but it makes a lot of sense in Florida. In MN we never had growth on the bottom so no worries.
 

DryLand404

New Member
It should come out easily so no silicone or other goo required. It could be a bad o-ring, a replacement that was a different manufacturer but old thru-hull". I know, this is not helpful ☺.
Thanks, I'll pull it and see what's going on . Could just need new O rings. I haven't found the plug anywhere on the boat. Quite a few bungs around though for plugging such throughhulls.
 

stnick

lee nicholas
in Florida the wheel type speed sensor will clog up and not work in 3 weeks. The barnacles will get it to stop. I had such a problem with that on my Sabre I changed it out to a high tech one by AMAIR the senses water speed and water temp. And the dam thing went south 4 mints later and ADMIR would NOT stand behind it !!! Ive got there number ! And they make 90 % of all the thru hulls and water sencors !!
 

wild382

John
GPS speed is more accurate anyway than paddle wheels.
On one tack it’ll read 9 knots and on the opposite 6.5...they only stay the same if centered on keel. Just a reference...not used when accuracy counts.
 

DryLand404

New Member
Could be a combo sensor.
I haven't been under the water to feel what the outer feels like.
I set out to stop the drip Saturday and made it worse when I slightly tightened down the plastic nut.
Water started spraying - Long story short.
After I tried to stop the drip Faring block fell apart when I moved it. Wood Only faring block and not sealed with resin or attached to the hull. Also the hole in the faring block seems to large for the plastic threaded pipe.
(Photo attached- pulled and bedded with WaterWeld Putty and reseated with a plastic liner between the faring block and putty)
For now back to just 1 drip every 3 seconds. Will have all trough hulls thoroughly checked when I have her pulled.
 

Attachments

wild382

John
Could be a combo sensor.
I haven't been under the water to feel what the outer feels like.
I set out to stop the drip Saturday and made it worse when I slightly tightened down the plastic nut.
Water started spraying - Long story short.
After I tried to stop the drip Faring block fell apart when I moved it. Wood Only faring block and not sealed with resin or attached to the hull. Also the hole in the faring block seems to large for the plastic threaded pipe.
(Photo attached- pulled and bedded with WaterWeld Putty and reseated with a plastic liner between the faring block and putty)
For now back to just 1 drip every 3 seconds. Will have all trough hulls thoroughly checked when I have her pulled.
This looks like a very old sensor and fitting mount...
We replaced ours a few years ago with one similar to this
https://www.blueheronmarine.com/products/raymarine-st50-speed-temp-transducer-st800-p-5
 

DryLand404

New Member
Just following up on this post.
This was a depth finder thru hull. Turns out there was a second one on the port side.
This one had started leaking and rotted out the fairing block that was keeping is vertical. The Fairing block was not glassed resined or mounted to the hull and was serving as only a spacer.
I had the thru hull filled and patched while we had her pulled out for the bottom paint and diesel replacement.
 
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