Propeller shaft, coupler and struts - Page 2 - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance
 Not a Member? 


Like Tree8Likes
Reply
 
LinkBack Thread Tools
  #11  
Old 07-15-2014
mitiempo's Avatar
Senior Member
 
Join Date: Sep 2008
Location: Victoria B.C. Canada
Posts: 7,220
Thanks: 0
Thanked 73 Times in 64 Posts
Rep Power: 8
mitiempo will become famous soon enough mitiempo will become famous soon enough
Re: Propeller shaft, coupler and struts

Quote:
Originally Posted by Westsailforever View Post
Strut should be bronze not SS .
And not 1.5 to 2k either!
__________________
Brian
Living aboard in Victoria Harbour
Reply With Quote Quick reply to this message Share with Facebook
  #12  
Old 07-15-2014
boatpoker's Avatar
Senior Member
 
Join Date: Jul 2008
Location: Toronto
Posts: 1,061
Thanks: 8
Thanked 25 Times in 24 Posts
Rep Power: 7
boatpoker is on a distinguished road
Re: Propeller shaft, coupler and struts

Bronze contains about 15% zinc. When the piece suffers from electrolytic corrosion (either galvanic or stray current) the zinc dissolves leaving the bronze with a pinkish hue and visible pitting on surface. A strut in this condition is seriously weakened. I have seen a strut break under power and stay on the shaft getting whipped around 800 (shaft) RPM and digging a hole in the hull before the shaft fell out.

Not enough information provided to say if the cause is galvanic or stray current but it is certainly not "electrolysis" which is a commonly misused term by those who do not understand electrolytic corrosion. Galvanic corrosion is a fairly slow process while stray current corrosion can be a shockingly (pun) fast process. If stray current is the culprit you may have an electrically unsafe boat.

Can't tell from the photo but your propeller must also be suspect. Very few propellers are bronze, most are actually manganese bronze which is actually a brass which contains around 35% zinc. If the strut is compromised the propeller is in likely worse condition.
mitiempo and stef9sailnet like this.
__________________
Dirt People Scare me

Last edited by boatpoker; 07-15-2014 at 07:33 AM.
Reply With Quote Quick reply to this message Share with Facebook
  #13  
Old 07-15-2014
Senior Member
 
Join Date: Jan 2013
Location: Montreal, QC, Canada
Posts: 272
Thanks: 0
Thanked 13 Times in 12 Posts
Rep Power: 2
sony2000 is on a distinguished road
Re: Propeller shaft, coupler and struts

The coupling is finished. The stuffing box and shaft maybe salvageable. Then change the cutlass bearing, and stuffing. Now if your lucky, and the strut survives the removals, add some fiberglass to support the root of the strut.
Reply With Quote Quick reply to this message Share with Facebook
  #14  
Old 07-15-2014
jimrafford's Avatar
Senior Member
 
Join Date: Jan 2011
Location: ct
Posts: 580
Thanks: 0
Thanked 11 Times in 11 Posts
Rep Power: 4
jimrafford is on a distinguished road
Re: Propeller shaft, coupler and struts

I just did this job on my boat back in may. We were pressing the cutlass bearing out and the strut fell apart. This work must be done on the hard so if your out now, fix it now. It's not rocket science. Get a 4 1/2" grinder and split the coupler. You can't change the stuffing box gland w/o removing the coupler.
If the strut fails, (trust me it will happen when you really need the motor) the flailing prop and strut can hole the boat. Forget about the fiberglass BS. Fix it properly before you leave.
Jim
__________________
S/V Deja Vu
CS 40
Reply With Quote Quick reply to this message Share with Facebook
  #15  
Old 07-15-2014
Maine Sail's Avatar
Senior Member
 
Join Date: Jan 2003
Location: Maine Coast
Posts: 5,484
Thanks: 12
Thanked 137 Times in 105 Posts
Rep Power: 15
Maine Sail is just really nice Maine Sail is just really nice Maine Sail is just really nice Maine Sail is just really nice
Re: Propeller shaft, coupler and struts

Quote:
Originally Posted by thevdeub View Post
How bad is it ?
We hauled the boat (Tartan 37', 1977), planning to install a drip less packing gland.
Now, the yard seems to think the strut is really weak and should be changed, and it is unlikely that the shaft will ever come out of the coupler and is corroded inside. I would expect the bill to come down with a full new shaft and strut, i.e. 3 to 5k$.
Other people tell me that this is expected on an old boat and there is nothing to really worry about.
I would prefer plan the full repairs in a couple of years, if this is not 'unsafe'.
In a couple of years, I might have more time to plan for this financially and maybe do the work myself.

Any opinions ? Can I wait ?

ps: I am planning for a pacific crossing, CA to HI, not much motor involved, if any.

That strut is beyond gone and dezincification has won the battle.....

Contact Brewer's South Freeport Marine in South Freeport Maine. They just did a Tartan 37 strut and had it custom cast because they are simply not available. John Brewer should be able to tell you whom he had cast the strut. I believe it was in Mass.

With the strut looking like that I would move forward with a full corrosion survey by a competent corrosion specialist. Your board, board pin. thru-hulls etc. could also be damaged.
jrd22 and stef9sailnet like this.
__________________
______
-Maine Sail / CS-36T


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




© Images In Posts Property of Compass Marine Inc.



Last edited by Maine Sail; 07-15-2014 at 05:58 PM.
Reply With Quote Quick reply to this message Share with Facebook
  #16  
Old 07-16-2014
Member
 
Join Date: Apr 2010
Location: Maui, HI
Posts: 77
Thanks: 2
Thanked 0 Times in 0 Posts
Rep Power: 5
thevdeub is on a distinguished road
Re: Propeller shaft, coupler and struts

Alright. Another picture grinding the .5mm of pink layer. If I understand correctly, the metal is deeply weakened, and not only in surface. The gold/Yellow layer looks really stronger than the pink cupper in surface. This is not rocket science but a lot of work and a very inaccessible area (Hot Water tank, ...), and I woould have preferred attacking this in one year or so, with more time in front of me and in a cheaper yard.
I have been quoted for 400$ for the pattern + 600$ for the strut. Add a coupler, a shaft ...
Anyway, thanks for the feedback. and the contact in South Freeport, Maine.
Cheers
Attached Thumbnails
Propeller shaft, coupler and struts-strutsmall.jpg  
Reply With Quote Quick reply to this message Share with Facebook
  #17  
Old 10-03-2014
Member
 
Join Date: Apr 2010
Location: Maui, HI
Posts: 77
Thanks: 2
Thanked 0 Times in 0 Posts
Rep Power: 5
thevdeub is on a distinguished road
Re: Propeller shaft, coupler and struts

For the archives.

We ended doing the work professionally. We had to change the shaft as well, and the packing gland. Overall, adding Strut and Coupler, it ended up almost 2K for the parts.
The bronze strut has been made by marine hardware .com based on the template of the old one. I did all the cleaning, removal etc.. myself, but putting back everything together and aligned - professionally - came back around 1.5K.
Close from the original estimate. But at least, the job is strong and well done, and I should be good for the next 20 years.


http://4.bp.blogspot.com/-8GU531b6ET...Boat%2B037.jpg
Reply With Quote Quick reply to this message Share with Facebook
  #18  
Old 10-03-2014
davidpm's Avatar
Senior Member
 
Join Date: Oct 2007
Location: Madison
Posts: 3,808
Thanks: 204
Thanked 50 Times in 42 Posts
Rep Power: 8
davidpm is on a distinguished road
Re: Propeller shaft, coupler and struts

Quote:
Originally Posted by thevdeub View Post
Thanks for comming back with the follow up. A lot of folks don't and it is really nice to see how things work out.

Looks awesome.
__________________
The lesson from the Icarus story is not about human failing.
It is a lesson about the limitations of wax as an adhesive.
If you have an engineering problem solve it.
Reply With Quote Quick reply to this message Share with Facebook
  #19  
Old 10-03-2014
Member
 
Join Date: Apr 2010
Location: Maui, HI
Posts: 77
Thanks: 2
Thanked 0 Times in 0 Posts
Rep Power: 5
thevdeub is on a distinguished road
Re: Propeller shaft, coupler and struts

Thanks. It took a while to close this thread, because it took actually a while to get it done. Overall, almost took 2 months (!!!!). 3 Weeks to get the strut done, we had some parts issues, the yard was busy, etc... Make sure you have a good yard that do not make pay the lay days while waiting for parts
Reply With Quote Quick reply to this message Share with Facebook
  #20  
Old 10-04-2014
jimrafford's Avatar
Senior Member
 
Join Date: Jan 2011
Location: ct
Posts: 580
Thanks: 0
Thanked 11 Times in 11 Posts
Rep Power: 4
jimrafford is on a distinguished road
Re: Propeller shaft, coupler and struts

Very smart to get it done. From personal experience it's a real PIA when things like this need to be done but well worth it once finished.
Have a safe voyage
Jim
__________________
S/V Deja Vu
CS 40
Reply With Quote Quick reply to this message Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Replacing the hose between the propeller shaft stuffing box and shaft log tube jameswilson29 Gear & Maintenance 34 12-14-2011 05:20 PM
Shaft Coupler Key Tanley Gear & Maintenance 3 06-07-2010 09:28 AM
Shaft coupler woes jr438234606 Gear & Maintenance 24 11-12-2008 10:44 PM
Shaft Coupler to Shaft attachment dhornsey Gear & Maintenance 20 06-30-2008 03:07 PM
prop shaft coupler thurston Gear & Maintenance 2 12-31-2001 07:00 AM


All times are GMT -4. The time now is 12:27 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.