Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 04-09-2012, 19:28   #1
Registered User
 
Reefmagnet's Avatar

Join Date: May 2008
Location: puɐןsuǝǝnb 'ʎɐʞɔɐɯ
Boat: Nantucket Island 33
Posts: 2,734
Speed Log Paddle Wheel Won't Spin in Water

I have installed a new Nexus NX system into my boat to replace an old Nexus/Silva system. I never used the old system which used the same holes and layout, so I don't know how well it worked when it was working, but I can't get the log paddle wheel to spin when fully inserted into the thru hull housing. The weird thing is that if I pull it slightly from the housing, it will spin - albeit not very well. When spun by hand (in air) it spins and reads perfectly.

The only thing I can think that is causing it not to spin is disrupted water flow (yes I've double and triple checked the paddle wheel is facing the right way when mounted!). The depth transducer is mounted about 8" or so in front of the log, so I'm guessing this would be the culprit.

Does this sound likely, or does anyone have any other theories on why the paddle wheel doesn't want to spin?
__________________

__________________
Reefmagnet is offline   Reply With Quote
Old 04-09-2012, 19:33   #2
Moderator Emeritus
 
Ex-Calif's Avatar

Cruisers Forum Supporter

Join Date: May 2007
Location: Singapore
Boat: Maxi 77 - Relax Lah!
Posts: 11,514
Images: 4
Re: Speed Log Paddle Wheel Won't Spin in Water

Did you use a new thru hull that came with the log. The new/matched thru hull is also designed to set the penetration depth of the log.
__________________

__________________
Relax Lah! is For Sale <--- Click
Click--> Custom CF Google Search or CF Rules
You're gonna need a bigger boat... - Martin Brody
Ex-Calif is offline   Reply With Quote
Old 04-09-2012, 19:38   #3
Registered User
 
Reefmagnet's Avatar

Join Date: May 2008
Location: puɐןsuǝǝnb 'ʎɐʞɔɐɯ
Boat: Nantucket Island 33
Posts: 2,734
Re: Speed Log Paddle Wheel Won't Spin in Water

Quote:
Originally Posted by Ex-Calif View Post
Did you use a new thru hull that came with the log. The new/matched thru hull is also designed to set the penetration depth of the log.
Yes, I replaced all the hardware including thru hulls - I just used the original holes.
__________________
Reefmagnet is offline   Reply With Quote
Old 04-09-2012, 19:44   #4
Registered User
 
svHyLyte's Avatar

Join Date: Mar 2006
Location: Tampa Bay area, USA
Boat: Beneteau First 42
Posts: 3,419
Images: 25
Re: Speed Log Paddle Wheel Won't Spin in Water

Turn it around. It will have no choice but to spin unless you have obstructed it entirely.
__________________
"It is not so much for its beauty that the Sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."
svHyLyte is online now   Reply With Quote
Old 04-09-2012, 19:48   #5
Moderator Emeritus
 
Ex-Calif's Avatar

Cruisers Forum Supporter

Join Date: May 2007
Location: Singapore
Boat: Maxi 77 - Relax Lah!
Posts: 11,514
Images: 4
Re: Speed Log Paddle Wheel Won't Spin in Water

Hmmm. If the suspicion is the area at the log is cavitating then remove the log while under way.

If it is cavitating no water should gush in.

If water gushes in then put it back in the other way round - LOL...

Does the depth sounder really have a large protuberance?

Strange issue.
__________________
Relax Lah! is For Sale <--- Click
Click--> Custom CF Google Search or CF Rules
You're gonna need a bigger boat... - Martin Brody
Ex-Calif is offline   Reply With Quote
Old 04-09-2012, 19:57   #6
Registered User
 
Reefmagnet's Avatar

Join Date: May 2008
Location: puɐןsuǝǝnb 'ʎɐʞɔɐɯ
Boat: Nantucket Island 33
Posts: 2,734
Re: Speed Log Paddle Wheel Won't Spin in Water

Ok, I have tried it swapped around (and tested that it shouldn't matter which way it goes in that sense, which it doesn't). Ex-Calif - I did pull it out while moving and considerably less water gushed out then at a standstill, although we were heeled over at the time placing the transducer on the high side of the boat.

I tried to swap the depth and log over, but the depth was glued in by the new antifouling (do-uh) so I didn't want to horse around getting it free while we were in transit. I've since freed it and relocated it to the logs former spot at the rear so intend to try it with the log in the front hole next trip. The only issue with this is that the manual says to mount the depth in front in this situation to, surprise, avoid problems with cavitation.

It's a weird one for sure.
__________________
Reefmagnet is offline   Reply With Quote
Old 04-09-2012, 20:06   #7
Registered User
 
Gene :^)'s Avatar

Join Date: Mar 2008
Boat: 1914 Fantail M.Y. "Strathbelle"
Posts: 222
Maybe it is a glob of excess bottom paint stopping the wheel when you push it all the way in. You said the sounder had excess paint glueing it in place, it would stand to reason that both were painted sloppy.

-----

Gene :^)
Http://www.Strathbelle.com/
__________________
Gene :^)

1914 Fantail Motor Yacht of Riveted Iron & Steel
http://www.Strathbelle.com
Gene :^) is offline   Reply With Quote
Old 04-09-2012, 20:26   #8
Registered User
 
Reefmagnet's Avatar

Join Date: May 2008
Location: puɐןsuǝǝnb 'ʎɐʞɔɐɯ
Boat: Nantucket Island 33
Posts: 2,734
Re: Speed Log Paddle Wheel Won't Spin in Water

That could indeed be a possibility Gene. Although it won't be something directly in contact with the log as I had a quick look (very quick!) while swapping the transducer for a plug.
__________________
Reefmagnet is offline   Reply With Quote
Old 04-09-2012, 20:30   #9
Registered User
 
Gene :^)'s Avatar

Join Date: Mar 2008
Boat: 1914 Fantail M.Y. "Strathbelle"
Posts: 222
I think you need to dive under the boat and make sure it can spin free with your finger when installed. May have nothing to do with the water flow.

-----

Gene :^)
Http://www.Strathbelle.com/
__________________
Gene :^)

1914 Fantail Motor Yacht of Riveted Iron & Steel
http://www.Strathbelle.com
Gene :^) is offline   Reply With Quote
Old 04-09-2012, 20:33   #10
Registered User
 
Reefmagnet's Avatar

Join Date: May 2008
Location: puɐןsuǝǝnb 'ʎɐʞɔɐɯ
Boat: Nantucket Island 33
Posts: 2,734
Re: Speed Log Paddle Wheel Won't Spin in Water

Yes, I'll be doing that this weekend. It has me intrigued.
__________________
Reefmagnet is offline   Reply With Quote
Old 04-09-2012, 20:44   #11
Moderator Emeritus
 
Ex-Calif's Avatar

Cruisers Forum Supporter

Join Date: May 2007
Location: Singapore
Boat: Maxi 77 - Relax Lah!
Posts: 11,514
Images: 4
Re: Speed Log Paddle Wheel Won't Spin in Water

It would be interesting if you have shore water to take a hose down with you and simulate water flow while watching the wheel and someone videoing the gauge up top.
__________________
Relax Lah! is For Sale <--- Click
Click--> Custom CF Google Search or CF Rules
You're gonna need a bigger boat... - Martin Brody
Ex-Calif is offline   Reply With Quote
Old 12-09-2012, 05:43   #12
Registered User
 
Reefmagnet's Avatar

Join Date: May 2008
Location: puɐןsuǝǝnb 'ʎɐʞɔɐɯ
Boat: Nantucket Island 33
Posts: 2,734
Re: Speed Log Paddle Wheel Won't Spin in Water

Just an update. I swapped the log to the front thru hull and the depth sounder to the rear thru hull last weekend and both worked perfectly. Didn't get a chance to dive under to have a look, so am yet to confirm if there is any gunk over the rear hole.
__________________

__________________
Reefmagnet is offline   Reply With Quote
Reply

Tags
water, wheel

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 06:33.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.