Autohelm Tridata Speed Sensor

[AuroraGH]

I left my speed sensor in the water and it seems my diver clobbered it with a scraper. It is an old Autohelm Tridata (since acquired by Raymarine I think).

Link to image gallery

I've seen paddlewheel replacement kits but I don't know if that's what I need or is it easier to just get a replacement sensor? Where would I find one? Searching Raymarine's site hasn't yielded anything useful.

Thanks.

[atoll]

Originally Posted by AuroraGH

I left my speed sensor in the water and it seems my diver clobbered it with a scraper. It is an old Autohelm Tridata (since acquired by Raymarine I think).

Link to image gallery

I've seen paddlewheel replacement kits but I don't know if that's what I need or is it easier to just get a replacement sensor? Where would I find one? Searching Raymarine's site hasn't yielded anything useful.

Thanks.

the transducers raymarine use are made by airmar
AIRMAR

[Dsanduril]

Check the Ray ST800/P120. That works with the ST60 Tridata, which I think was the last Autohelm version. Not sure if the Autohelm ST50 and earlier used the same.

Defender has it for less than $100, West Marine also carries it if you want to actually look at one to compare.

[Calif.Ted]

Looks like a paddlewheel replacement is all you need, never seen anything like that before, hope he wasn't that aggressive on your prop.

[CS40 Elixir]

I just went through a similar episode with mine. There are several places online you can find the paddle wheel. I replaced mine with one from a left over wheel from a new BG/Simrad and it worked fine. I wouldn't be too quick to blame the diver, I see there is growth around where the paddles were and the sides were not damaged. Mine lost 1/2 a tooth and and read about 1/2 speed and a while later an entire tooth fell off. We thought it could have been from scrubbing, but don't see how it could have been when the sides protect it and the other direction will just spin. With all the ones I saw online for sale, it must be pretty common.
Cheers

[CarinaPDX]

Everything looks fine, except for the paddlewheel. It is an easy replacement. Get on to AIRMAR and get the paddlewheel kit from them. As stated earlier they are the actual manufacturer of the device. IIRC the plastic paadlewheel turns on a SS shaft and is removed by carefully spreading the sides a small amount and working one end of the shaft out of the plastic socket. Be careful not to break it - it is pretty sturdy but don't push it. If it were me I would contact Airmar support: Contact Us/Locations | AIRMAR

Greg

[Alita49DS]

Looks completely b*g*ered to me. You need an ST600 sensor. I have the info sheet if you PM me. Go to AIRMAR and search for it. Check the hole size, on the sheet, as otherwise you will have to lift the boat.

The real pain is that you are not meant to cut the cable. So be prepared for hours of fun threading it through the boat to the instrument.

[CarinaPDX]

What do you see that is "buggered" besides the paddlewheel? It looks fine to me, with the exception of the paddlewheel - it just needs cleaning and a new paddlewheel. I've pulled one out with a lot more growth on it and it cleans up well. I have also replaced the paddlewheel, which I consider normal maintenance. Thinking about it I may buy a spare to have for my new smart tri-ducer. This is not a big deal.

Greg

[Alita49DS]

Originally Posted by CarinaPDX

What do you see that is "buggered" besides the paddlewheel? It looks fine to me, with the exception of the paddlewheel - it just needs cleaning and a new paddlewheel. I've pulled one out with a lot more growth on it and it cleans up well. I have also replaced the paddlewheel, which I consider normal maintenance. Thinking about it I may buy a spare to have for my new smart tri-ducer. This is not a big deal.

Greg

Look at the picture closely and then look at the data sheet I cited. You will see what appears to be a large chunk of the frame missing. Also cracking.

[CarinaPDX]

I have reviewed the OP's photos and find nothing at all amiss. I did look at the Airmar site and only found the "Owners Guide and Installation Instructions", which only has drawings, but again I don't see anything there that is different. Perhaps you could take a copy of the photo and add arrows or circles to show what you think is suspect? Also, upload the brochure as it will have the dimensions for comparison to newer products.

There are 2 listings on ebay.ca for the paddlewheel/o-ring kit at about $50cad. I would buy one of these unless there was a decision to replace.

If the OP wants to replace then those dimensions are critical. It might be possible to use the existing thru-hull but it would have to be checked closely. A generic Airmar tri-ducer should work well by splicing into the existing cable, or better see if there is a RM version with the right plug. Personally if there is a decision to replace I would install a "smart" transducer, either NMEA 0183 or 2000 with an appropriate head. The world is moving on...

Greg

[CarinaPDX]

I just found this: Gemeco | ST600 Transducers Gemeco is the main distributor of Airmar products if I understand correctly. Anyway, it shows that an ST800 transducer will be a direct replacement for the ST600 if required.

Edit: Take a look here: http://www.airmar.com/xref.html?refid=ST800 to find the part number for the ST800 with the matching connector for your head unit (pages 4 & 5).

Edit #2: Gemeco has the paddlewheel kit, part no. 33-250.

Edit #3: Hi from another Cape George owner!

Greg