Speed Paddle Wheel Keeps Sticking

[backcreeksailor]

I'm guessing it's probably marine beasties or just algae, but everytime I take my boat out, the speed sensor paddle wheel is stuck and doesn't work. After a couple hours out, it finally free's up and I get to see how fast I'm going on the way back to the slip. (This is the paddle wheel sensor that came with the Raymarine Tridata ST60).

Are there any options for fixing this so it works all the time instead of intermittently like this?

Or do all paddle wheels gum up like this on a regular basis?

* If it makes any difference, I'm in the upper Chesapeake Bay *

[dragonfly203]

I have the same Raymarine 60 set up and it only worked a few weeks after bringing my boat down to Annapolis from the "fresh" water of Harve de Grace. I have tried pulling it out (that can get the heart racing !) when its not in use, spary lube and it continues to be inconsistent at best. Most of the time it just reads 0.0...

There must be a better system that is available that can be swapped out in the same thru hull fitting. I too look for help in solving this 'currently' worthless device, which also throws off the wind vane speed.

Greg
Dragonfly
Annapolis

[JohnRPollard]

Originally Posted by backcreeksailor

I'm guessing it's probably marine beasties or just algae, but everytime I take my boat out, the speed sensor paddle wheel is stuck and doesn't work. After a couple hours out, it finally free's up and I get to see how fast I'm going on the way back to the slip. (This is the paddle wheel sensor that came with the Raymarine Tridata ST60).

Are there any options for fixing this so it works all the time instead of intermittently like this?

Or do all paddle wheels gum up like this on a regular basis?

* If it makes any difference, I'm in the upper Chesapeake Bay *

We gave up on the paddle wheel about ten years ago. It works fine when free of growth, but in the Chesapeake "free of growth" only lasts as long as the boat is moving.

We just leave the blank in all season now.

[noelex77]

Here in the Mediterranean paddle wheels are commonly effected by fouling. They can be cleaned, but many people are not prepared for the effort involved to keep them accurate. When my instuments were damaged by lightening I opted to go with 2 depth units (one is a fishfinder) which provides redudency for this important transducer.
Speed is provided by the GPS. There is little tide here and I have been impressed by the acuarcy and usufullness of SOG and the derived displays such as true wind. Much more usefull than an inacurate paddle wheel.
Be aware Raymarine St60 instruments will not give true wind from SOG,but other systems will.
An alternative is an ultrasonic speed transducer, expensive and some reports of unreliability, but newer transducers receive good reports if your speed is under 10K.

[backcreeksailor]

Originally Posted by dragonfly203

I have tried pulling it out (that can get the heart racing !)

I'm considering pulling it out cleaning it, but I'm a little leery because I keep hearing people like you say that it freaks them out when they do it. So how much water comes into the boat during the swap? And does it just pour in relatively slowly like a gallon per minute? Or are we talking firehose velocity, wet decks, and a full bilge in the time it takes to make the swap?

---

I found this stuff Transducer Antifouling Paint that claims it's specifically for antifouling on transducers. Which incidentally is what Raymarine recommends:

"To prevent fouling of the paddle wheel we would recommend that a thin coating of water-based anti fouling is applied to the paddle wheel itself."

But I would think that a spray on antifouling paint like Trilux Prop & Drive Spray Paint would allow you to put on a thinner, even coat than a brush on type.

[scottyt]

i just cleaned mine last weekend for the first time when down in your neck of the woods ( annapolis city dock) and it is easy. when i pulled it maybe a 1/2 gallon came in, but i did not have the plug in hand. when i put it back maybe 2 cups came in.

what you need to do is pull the pin, start it moving with both hands. once its moving pick up the plug with the spare hand i used my left to pull as i am right handed. then pull it out with the left hand shove the plug or wheel in with the right. it will be slightly stuck the first time you try to take it out, thats why you will need both hands to get it moving. make sure you put the pin in with the plug so it does not pop out.

the hardest part of the whole thing is getting the pin lined up.

[backcreeksailor]

Did you put any type of antifouling on yours, or did you just clean it and put it back in bare?

[tommays]

We have to leave ours out when NOT sailing or clean it once a week it has the BIG hole and requires a fast hand with the blank plug

[Hudsonian]

Smearing the o ring with a light film of silicone grease facilitates installation of the replacement plug and the paddle whell unit after cleaning. They'll be easier to align and remove also.

[billangiep]

Pulling the transducer really isn't a big deal even if you don't have the blank. There is a flapper valve of sorts that stops most of the water from entering the boat. You really would be surprised how little water comes in.
When reinstalling coating the O-rings with a bit dielectric or similar will help in future removal. When sliding the transducer back in place make sure you correctly align back into the notches. The transducer has an arrow embossed in the plastic (difficult to see) make sure it's pointing forward.
I keep mine in working order, along with the GPS when entering passes and such you can compare the two at a glance and know which way the tide is running and how fast.
Bill,