Ask a stupid question ...

[Dougie_the_Mate]

3 years ago we fitted a Clipper Log. Sometimes it did not register, but I put it down to marine life clogging the paddle wheel. This season however despite cleaning it thoroughly and applying a wee bit anti foul it never registered any readings at all.

The boat came out last week and the bottom was exceptionalyl clean. When I took the log out the paddle spun very freely and showed no evidence of any fouling. When I looked at it today I noticed that there was an arrow - obviously indicating the correct way it should be fitted.

Is it possible (here's the question) that I may have put it in back to front. If so would it simply not have functioned correctly?

Any advice gratefully received!

 

[{151760}]

We also have a Clipper. You certainly have to have it pointing the right way. In 2014 I checked it. It worked fine when I span the wheel with the boat ashore, but it didn't work at all in the water. The hub of the little wheel was split when I looked closely, so I put a new wheel in for the 2015 season, and it worked some of the time, until the boat was left on its mooring for a couple of weeks when it became fouled and stopped working. It needs clearing regularly, I guess.

 

[lpdsn]

If it was 180 deg out, I don't think it should've made any difference.

As I understand it, the sensors generally rely on generating an electrical pulse for each rotation using the hall effect. It should make no difference which way round the wheel is spinning.

I think the arrow is so that you don't get it misaligned. 90 degs out would be much worse.

Did it work better when you were going astern?

 

[Poignard]

Mine works with the arrow pointing forward or aft.

 

[RichardS]

The ones I've had usually have a ridge in the plastic housing that stops you putting them in the wrong way round but it sounds like the Clipper ones don't.

Richard

 

[TSB240]

3 years ago we fitted a Clipper Log. Sometimes it did not register, but I put it down to marine life clogging the paddle wheel. This season however despite cleaning it thoroughly and applying a wee bit anti foul it never registered any readings at all.

The boat came out last week and the bottom was exceptionalyl clean. When I took the log out the paddle spun very freely and showed no evidence of any fouling. When I looked at it today I noticed that there was an arrow - obviously indicating the correct way it should be fitted.

Is it possible (here's the question) that I may have put it in back to front. If so would it simply not have functioned correctly?

Any advice gratefully received!

Check the magnet in one of the vanes of the impeller has not corroded or fallen out! Do you get a reading if you blow on it to make it spin? If not probably need a new impeller!

 

[Dougie_the_Mate]

Thanks folks for the input. I would not have thought that blowing on it would have registered, but I will try that next time we are up.

I suppose the really stupid question is the one you don't ask!

 

[William_H]

I could get well over 10 knots registered by blowing on my old Smiths paddle wheel. So yes the ideal is to test before you refit by blowing on it.
As said it should be OK with 180 degree error but a 90 degree error will have water flow in the direction of the axle so no paddle wheel turning. good luck (or do what I do and get a GPS for speed readout) olewill

 

[AntarcticPilot]

Mine works with the arrow pointing forward or aft.

Mine doesn't! I once put it in wrong way round, and it didn't work at all. Put it in the right way, and it worked fine.

 

[{151760}]

Mine doesn't! I once put it in wrong way round, and it didn't work at all. Put it in the right way, and it worked fine.

Mine too.

 

[AntarcticPilot]

Mine too.

Mine's a Raymarine St60

 

[Spirit of Glenans]

If it doesn't register when you spin the paddlewheel you could remove and test it to see if the magnet is still in the paddle. A compass needle, for instance, will indicate whether or not it's present or another magnet should attract or repel it, depending on orientation. If you find that there is a magnet then you do need a new impeller. If there is no magnet, then all you need is a new paddlewheel, obtainable from
http://www.nasamarine.com/proddetail.php?prod=15_Paddlewheel