Shaft coupling removal and reinstallation - SailNet Community
 2Likes
Reply
 
LinkBack Thread Tools
post #1 of 31 Old 02-29-2012 Thread Starter
Tundra Down
 
downeast450's Avatar
 
Join Date: Jan 2008
Location: Seal Harbor, Maine
Posts: 1,274
Thanks: 50
Thanked 21 Times in 20 Posts
Rep Power: 8
 
Shaft coupling removal and reinstallation

After reading stories of the difficulties removing a shaft coupling I started spraying the one on our Atomic 4 with PBB a year ago. Yesterday I began tightening the three extra long bolts that are shimmed with washers and pull the shaft back to the transmission flange. There is a socket in the center of the coupling that is pushing back on the end of the shaft, forcing it out of the coupling as I tighten the bolts. Thank you Mr. Calder. It is working. The coupling has moved about 3/4" off the shaft. I did apply some heat on two occasions. Because of the limited space between the flange on the engine / transmission side and the transmission housing, washers have to be added as the socket pushes the shaft further out of the coupling flange. There isn't a lot of working room. It is a one hand operation, lying on my side fighting off muscle cramps! Fun! I started with two washers on each bolt and have added two more. I am out of 3/8" lock washers so I had to stop. I expected it to "let go" before the shaft traveled 1/2"? It is well passed that! I will find out next week how many washers it takes. Anybody care to guess?

What is now beginning to concern me is how I will get it back on to the depth it was when I began. I haven't read any advice about this. I will certainly "polish" both the shaft and the inside of the coupling but don't have a plan for "hammering it home"? Is putting one of these things back on a problem, too? I suppose I can heat the flange and cool the shaft?





Down

Last edited by downeast450; 02-29-2012 at 11:31 AM. Reason: sp
downeast450 is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 31 Old 02-29-2012
ancient mariner
 
captbillc's Avatar
 
Join Date: Jul 2008
Location: duluth ,minnesota
Posts: 439
Thanks: 1
Thanked 2 Times in 2 Posts
Rep Power: 8
 
after you install a new seal you would not want to ruin it with a hot flange ( if this is the flange you are talking about ) i have used a special puller that fits in the hole on the flange and screws on the shaft threads. use a little lubrication so the flange & shaft don't seize together.

Liberals are people who care about others. Freethinkers are not constrained by the myths of religion.
captbillc is offline  
Quote Quick Reply Share with Facebook
post #3 of 31 Old 02-29-2012 Thread Starter
Tundra Down
 
downeast450's Avatar
 
Join Date: Jan 2008
Location: Seal Harbor, Maine
Posts: 1,274
Thanks: 50
Thanked 21 Times in 20 Posts
Rep Power: 8
 
Different flange, Capt.

Down
downeast450 is offline  
Quote Quick Reply Share with Facebook
post #4 of 31 Old 02-29-2012
Senior Member
 
Join Date: Aug 2000
Posts: 334
Thanks: 1
Thanked 2 Times in 2 Posts
Rep Power: 16
 
By hand....

The coupling should go on by hand. Take the shaft and the flange to a machine shop and have them check the shaft for alignment and fit the flange. The flange should slide on/off the shaft with minimum effort. Make sure they drill a "dent" for the locking bolt, and that the bolt has a retaining wire hole to permit it to be lock wired in place.

Ref PBB, great stuff but use caution around gaskets etc;

PB Penetrating Catalyst FAQ's

Have fun.



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


gtod25 is offline  
Quote Quick Reply Share with Facebook
post #5 of 31 Old 02-29-2012
the pointy end is the bow
 
erps's Avatar
 
Join Date: Aug 2006
Location: La Conner, Washington
Posts: 6,260
Thanks: 2
Thanked 27 Times in 26 Posts
Rep Power: 11
   
Quote:
I started with two washers on each bolt and have added two more. I am out of 3/8" lock washers so I had to stop. I expected it to "let go" before the shaft traveled 1/2"? It is well passed that! I will find out next week how many washers it takes. Anybody care to guess?
I can still see shaft through the lock bolt hole, so count on another inch of travel at least. I'd buy a couple sets of shorter bolts.

Quote:
What is now beginning to concern me is how I will get it back on to the depth it was when I began. I haven't read any advice about this.
Take a file and make a light mark on the shaft where the flange ended before you clean it up with fine sandpaper.

Ray
S.V. Nikko
1983 Fraser 41
La Conner, WA


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


Boating for over 25 years, some of them successfully.
erps is offline  
Quote Quick Reply Share with Facebook
post #6 of 31 Old 02-29-2012
Senior Member
 
Maine Sail's Avatar
 
Join Date: Jan 2003
Location: Maine Coast
Posts: 5,890
Thanks: 20
Thanked 223 Times in 170 Posts
Rep Power: 16
       
Quote:
Originally Posted by downeast450 View Post
After reading stories of the difficulties removing a shaft coupling I started spraying the one on our Atomic 4 with PBB a year ago. Yesterday I began tightening the three extra long bolts that are shimmed with washers and pull the shaft back to the transmission flange. There is a socket in the center of the coupling that is pushing back on the end of the shaft, forcing it out of the coupling as I tighten the bolts. Thank you Mr. Calder. It is working. The coupling has moved about 3/4" off the shaft. I did apply some heat on two occasions. Because of the limited space between the flange on the engine / transmission side and the transmission housing, washers have to be added as the socket pushes the shaft further out of the coupling flange. There isn't a lot of working room. It is a one hand operation, lying on my side fighting off muscle cramps! Fun! I started with two washers on each bolt and have added two more. I am out of 3/8" lock washers so I had to stop. I expected it to "let go" before the shaft traveled 1/2"? It is well passed that! I will find out next week how many washers it takes. Anybody care to guess?

What is now beginning to concern me is how I will get it back on to the depth it was when I began. I haven't read any advice about this. I will certainly "polish" both the shaft and the inside of the coupling but don't have a plan for "hammering it home"? Is putting one of these things back on a problem, too? I suppose I can heat the flange and cool the shaft?





Down
Down,

This is supposed to be a light press fit. If you "polish" the OD of the shaft and ID of the coupling you will very likely lose this very delicate fit tolerance. It is not a bearing press fit like a cutlass to a strut but it is supposed to be a light press fit. If it just slides back on this = BAD!


As for getting a new coupling back on you can heat the coupling and cool the shaft or just guide it into place and use a wood mallet to "tap" the shaft into the coupling (usually takes 2 people to get it started). I color the dimple (spotting) in the shaft with a red sharpie marker then peer through the set screw hole with a flash light until it is lined up perfectly. If I am alone it takes MANY trips up and down the ladder to get it just perfect. The red dot makes it easier to see the spotting in the shaft.. I suspect someone on the island can fit and face a new coupling for you if your fit is destroyed...

P.S. Get full length threaded bolts and this will go faster.... You can also use threaded rod if you can find it in the right thread...

______
-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.


Maine Sail is offline  
Quote Quick Reply Share with Facebook
post #7 of 31 Old 02-29-2012 Thread Starter
Tundra Down
 
downeast450's Avatar
 
Join Date: Jan 2008
Location: Seal Harbor, Maine
Posts: 1,274
Thanks: 50
Thanked 21 Times in 20 Posts
Rep Power: 8
 
Thank you all for the information. I could put a longer socket in the space and probably will. The reason I was thinking about just adding washers is because of how tricky it is to get the socket to remain aligned with the end of the shaft and not fall out of the gap as you bring the flange up close enough to hold it while you get a bolt started. With one hand!

Maine, I will not "polish" it. Thanks! Heat is wonderful! Not sure how I could strike a couple of blows with a mallet. Perhaps a levered piece of 2x4 that pushes on the flange when I tap near the end?

Down
downeast450 is offline  
Quote Quick Reply Share with Facebook
post #8 of 31 Old 02-29-2012
Tartan 27' owner
 
CalebD's Avatar
 
Join Date: Jan 2008
Location: NYC
Posts: 4,794
Thanks: 5
Thanked 110 Times in 102 Posts
Rep Power: 8
 
Down,
Went through this with our A4 a couple of months ago. Pressing the coupling and shaft apart was torturous given our engine compartment. We found our bronze shaft to be worn at the stuffing box so we cut the shaft in 2 and it was much easier to remove the flange on a shop work bench.
2011, November 30th. Begin drive train rebuild | Odalisque
You probably have another 3/4" to 1" to go pressing your shaft out.

If your shaft is bronze you should consider that it might be easier to cut the shaft and pay around $200 for a new SS shaft. Have a prop shop spin your prop for balance and they can 'fit and face' your old coupler and make re-installation a very easy job by comparison to what you are doing now - which is a form of torture.
If your shaft is bronze it is likely 20 - 40 years old, therefore worth replacing.
You are planning on replacing the Cutless bearing as well as the shaft log hose, right?
Clean up and re-pack stuffing box and you have an as new drive train.

Good luck.

"The cure for anything is salt water~ sweat, tears, or the sea." ~Isak Denesen

Everybody has one:

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

Last edited by CalebD; 02-29-2012 at 12:45 PM.
CalebD is offline  
Quote Quick Reply Share with Facebook
post #9 of 31 Old 02-29-2012
Senior Member
 
Join Date: Aug 2000
Posts: 334
Thanks: 1
Thanked 2 Times in 2 Posts
Rep Power: 16
 
Listen to the master, O great one, MS.....

I stand corrected. Sorry MS, If I knew you were on I wouldn't even have posted. I must have missed the "press fit" part of your excellent instructional blog. Thanks for the correction.

Gerry



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


gtod25 is offline  
Quote Quick Reply Share with Facebook
post #10 of 31 Old 02-29-2012 Thread Starter
Tundra Down
 
downeast450's Avatar
 
Join Date: Jan 2008
Location: Seal Harbor, Maine
Posts: 1,274
Thanks: 50
Thanked 21 Times in 20 Posts
Rep Power: 8
 
CalebD,

That is my plan. It is a tedious PITA working in that cramped space. My shaft is ss. It is moving slowly, one washer at a time, Ha! I have plenty of time to finish forcing it out of the flange this way. It has become one of the tasks that I spend an hour or two on and then leave it until the next day I am aboard. If it wasn't moving I would be concerned. I think I will change the socket for a deeper one. With the shaft already moved 3/4" it may be easier to get a socket to stay put while I bring up the bolts.

PBB is great stuff but should be used carefully. I use paper towels for masking when I spray that stuff and remove the contaminated paper immediately. It is coming out of the flange with "color" so it is helping. WD-40 might be a better lubricant now that things are moving.

Taking care of the shaft is the last big chore left that came with the boat.

Down
downeast450 is offline  
Quote Quick Reply 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:
OR

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
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
shaft\coupling tolerance drobarge Gear & Maintenance 7 06-30-2011 05:42 PM
flex coupling/propshaft removal help? MitchM Gear & Maintenance 2 05-08-2011 03:32 AM
Flexible shaft coupling zerubb Gear & Maintenance 1 08-18-2006 11:13 PM
shaft coupling clifsail Announcements and Suggestions Box 1 08-15-2006 02:06 PM
prop shaft coupling kurt crowley Atomic 4 2 06-27-2006 03:45 PM

Posting Rules  
You may post new threads
You may 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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome