What is this on the bottom of my daysailer?
Posted by jocrow1996@reddit | sailing | View on Reddit | 12 comments

I found this valve on the bottom of my sailboat. It is on the aft end, about 2ft from the very end.
FredIsAThing@reddit
Missing a paddle wheel.
alex1033@reddit
It's a broken speed transducer
Apart_Exercise_5630@reddit
You all sure it’s not for the emergency tiller?
jocrow1996@reddit (OP)
It’s a tiller sailboat so I highly doubt it lol.
spongue@reddit
That's where the sea people come from beneath and attach a winch to drag you under
jocrow1996@reddit (OP)
That’s where the mother in law will sleep
spiffyweezie89@reddit
That's a "broken".
ozamia@reddit
It's not a valve, it's a paddle wheel speed log, missing the actual wheel (it's mostly plastic and has probably split and fallen off).
jocrow1996@reddit (OP)
Vielen Dank!
overthehillhat@reddit
probably DataMarine - - they made an O-Ring plug for that
MIght be easier to find at a consignment shop or a salty flea MKT
Whats it look like- from the inside??
Wire/Cable?
hlprmnkyRidesAgain@reddit
I concur, it looks exactly like the Datamarine knotmeter/log I had on an 80s Catalina 25. There is a shop (DMI Marine) that was in the business of selling both NOS parts for the old Datamarine kit and new hardware designed to fill the same physical mounts and kind of the same “80s tech” role but with newer innards, however it looks like the sole proprietor is winding the business down after some health issues.
They do still appear to have paddlewheel kits and dummy plugs available for now. I replaced the paddlewheel on mine with a DMI part several years ago and was very happy with the company and the quality of parts; it’s a shame that it looks like the knowledge base and expertise is retiring with the one person who kept it going.
TitusListens@reddit
Judging from the arrow and the perpendicular axis I would say it’s the remnant of a log/ speed transducer, where there should be a paddle wheel on that axis, rotating with a speed which varies with the boat speed but I maybe wrong