Return to the home page...

Go Back   Moyer Marine Atomic 4 Community - Home of the Afourians > Discussion Topics > Troubleshooting

Reply
 
Thread Tools Display Modes
  #1   IP: 134.41.129.72
Old 06-03-2021, 10:08 PM
Mo's Avatar
Mo Mo is offline
Afourian MVP
 
Join Date: Jun 2007
Location: Halifax NS,
Posts: 4,470
Thanks: 292
Thanked 411 Times in 272 Posts
Shaft Vibration saga.

Had a pretty pronounced vibration through my drive train on Odyssey the past few weeks. So much so that I didn't use the boat much. I tore the rotator cuff of my rt shoulder and can't reach and wrench so its been a cluster trying to get things done.

So, initially I was figuring the Cutless went. Bought one, rolled the trailer into the water and took the boat out onto the ramp to change it...it seemed fine. Anode was tight, and no visible warp in the shaft or prop. So backed it back into the water thinking I need to go to the reversing gear.

So next I thought perhaps the coupling was bad...I could hold my hand at the aft area of the reversing gear and it was rough. No leaks though and no whining to indicate a bearing. So I let it lay for a few days in hopes my shoulder would improve..not!

While I was taking it easy I went through the thoughts of pilot bearing, thrust bearing etc but didn't think it was that. Again, no oil leak, no whine. That boat had been running fine and this just seemed to start after about 2 weeks in the water.

I'd had her out in 6 foot seas the day before it happened but didn't note any problems at that time...she was in 25 knts knifing waves well healed over as well at that time.

Shoulder wasn't getting any better so a couple of guys offered to wrench for me and Id tell them what to do...so we went for an alignment and here's how we did it.

1. Loosened stuffing box so shaft could slide back.
2. Remove 3 bolts from coupling and slid shaft back an inch or so...it dropped about 1/16 of an inch.
3. Checked coupling for signs of wear...it was fine.
4. Eyeballed the center of the shaft to the rubber on the stuffing box...indications were the engine had to come down. That was just looking at it. So holding the shaft centered as we could in relation to the rubber (so trying to ensure a good alignment coming into the boat), we moved it toward the reversing gear. Figured we'd need mounts adjusted.
5. Loosened all motor mounts and using a feeler gauge on 4 sides of the coupling we adjusted mounts, both front and rear to have that flange of the coupling mount right up...please keep in mind that we eyeballed it center of the stuffing box rubber and not off to one side or the other nor high or low.
6. Then put the 3 bolts back in the coupling flange and finger tightened them.
7. When the 3 bolts on the coupling finger tight used a feeler guage to double check and finally tighten everything.

All 4 motor mounts had a slight adjustment and to be honest I really couldnt tell if we had it or not. The guys tightened everything up and we ran it up at the dock. Immediately there was notable improvement, the visible vibration of the port back stay was gone...the prop is off to that side.

We were at it for 3 hours and I figured we'd done as best we could and was thinking that next I change out a reversing gear. We called it a day and cleaned up. HOWEVER, a nice 18 kt breeze came up so I figured I get a sail in. As soon as I backed off the dock I knew it was better. Put the boat in forward and all I could feel was some prop wash on the rudder which went away once I got way on.

I can still feel something, or I think I do, but it is really, really smooth. Maybe I'm too particular. So I sailed for about an hour and as the sea built a little bit I drops the sails and motored into some chop. Felt pretty good. Motored the boat back to the dock, about 3 miles and all was fine.

So, that's where I am with it. I'd like thoughts from guys who had similar experiences. I put this engine in last fall, it ran fine without vibration. I'm thinking perhaps the engine shifted on rough sail earlier this year...or something could be on the way out.
__________________
Mo

"Odyssey"
1976 C&C 30 MKI

The pessimist complains about the wind.
The optimist expects it to change.
The realist adjusts the sails.
...Sir William Arthur Ward.

Last edited by Mo; 06-05-2021 at 09:59 PM.
Reply With Quote
The Following User Says Thank You to Mo For This Useful Post:
TimBSmith (06-04-2021)
  #2   IP: 32.211.28.40
Old 06-04-2021, 08:47 AM
Al Schober's Avatar
Al Schober Al Schober is offline
Afourian MVP
 
Join Date: Jul 2009
Location: Uncasville, CT
Posts: 2,002
Thanks: 16
Thanked 578 Times in 405 Posts
My guess would be that the engine shifted sideways a bit. The nuts and washers in the mounts are good at holding vertical alignment, but there is quite a bit of clearance between the bolts and the holes in the oil pan. I always recommend pouring some bondo into that gap to keep things from shifting.
Reply With Quote
The Following 2 Users Say Thank You to Al Schober For This Useful Post:
Mo (06-05-2021), TimBSmith (06-04-2021)
  #3   IP: 138.207.177.95
Old 06-04-2021, 10:21 AM
joe_db's Avatar
joe_db joe_db is offline
Afourian MVP
 
Join Date: May 2009
Posts: 4,474
Thanks: 49
Thanked 1,026 Times in 721 Posts
My shaft vibration issue was only cured with a new shaft. In your case the engine seems to have shifted on the mounts.
Reply With Quote
The Following User Says Thank You to joe_db For This Useful Post:
Mo (06-05-2021)
  #4   IP: 72.69.36.126
Old 06-04-2021, 01:39 PM
tenders tenders is offline
Afourian MVP
 
Join Date: May 2007
Location: Harlem YC, City Island, NY
Posts: 1,439
Thanks: 46
Thanked 259 Times in 170 Posts
How are the rails your mounts bolt into? One of mine was a corrosion disaster when my engine was pulled in 1994. It was chiseled out and replaced with stainless, but not quite precisely, which has resulted in 3/8" of misalignment and an annoying vibration and shaft seal leak since then.

This spring, which is rapidly turning into summer, I bit the bullet and am in the middle of fixing it right now, with new engine mounts, a bit more wiggle room drilled into the mounting holes, a bit of welding maintenance on the stainless standpipe muffler, and a whole host of other things that happen once you start digging around down there.
Reply With Quote
The Following 2 Users Say Thank You to tenders For This Useful Post:
Mo (06-05-2021), TimBSmith (06-04-2021)
  #5   IP: 134.41.129.72
Old 06-04-2021, 09:22 PM
Mo's Avatar
Mo Mo is offline
Afourian MVP
 
Join Date: Jun 2007
Location: Halifax NS,
Posts: 4,470
Thanks: 292
Thanked 411 Times in 272 Posts
Hi
Tenders:
My mounts are bolted to the rails...there is a piece of tapped angle iron bolted to each rail. The mounts are bolted through the angle iron into the wood.

Joe: I don't think it's the shaft.

Al: Sure sounds like it shifted. I just need to figure out if I damaged anything in the reversing gear. Right now it's not bad but I'd hate to be out on a little excursion and something deteriorate.

Any thoughts on bearings within the reversing gear that might have gotten damaged or worn?
__________________
Mo

"Odyssey"
1976 C&C 30 MKI

The pessimist complains about the wind.
The optimist expects it to change.
The realist adjusts the sails.
...Sir William Arthur Ward.
Reply With Quote
  #6   IP: 134.41.129.72
Old 06-05-2021, 09:43 PM
Mo's Avatar
Mo Mo is offline
Afourian MVP
 
Join Date: Jun 2007
Location: Halifax NS,
Posts: 4,470
Thanks: 292
Thanked 411 Times in 272 Posts
She might be OK.

Took her for another sail today. 25 nautical miles on the ocean. We left in very light air and motored out for about 45 minutes, with main up, until the wind built a bit. No issues at all at this point, no vibration or rattling. At this time I altered course about 30 degrees and unfurled the 100% jib and shut down the engine. Left the reversing gear in neutral and didn't hear anything I haven't heard for years...just a shaft spinning. Boat speed was initially around 5 kts then 6 and then holding 7 to 7.3 close hauled as the sea started to build up a bit. Just enough to send spray back across the deck occasionally. We carried on out to a buoy named HNWC (Navy) and then turned for home. I took a different course back in having the boat on a broad reach, in neutral. On the building sea state (not much actually) she ranged from 6.5 to 7 kts with the shaft spinning all the way back in and up the harbour. Here I turned her back to windward for about 10 minutes and dropped and packed away the main while underway on the jib. Near the club I furled the jib and fired up the engine...this is where I was experiencing a vibration/shutter previously at low rpm. Today the boat fired up, no vibration again, drove it to the dock, everything working as it had for years.
__________________
Mo

"Odyssey"
1976 C&C 30 MKI

The pessimist complains about the wind.
The optimist expects it to change.
The realist adjusts the sails.
...Sir William Arthur Ward.
Reply With Quote
The Following User Says Thank You to Mo For This Useful Post:
W2ET (06-05-2021)
  #7   IP: 104.174.83.118
Old 06-06-2021, 12:24 AM
ndutton's Avatar
ndutton ndutton is offline
Afourian MVP
 
Join Date: May 2009
Location: Torrance, CA
Posts: 9,619
Thanks: 198
Thanked 2,208 Times in 1,425 Posts
Unusual vibrations can be unnerving until their cause is determined. My experience from a few years ago:
https://www.moyermarineforum.com/for...ad.php?t=11273
__________________
Neil
1977 Catalina 30
San Pedro, California
prior boats 1987 Westsail 32, 1970 Catalina 22
Had my hands in a few others
Reply With Quote
The Following 2 Users Say Thank You to ndutton For This Useful Post:
Mo (06-06-2021), TimBSmith (06-08-2021)
  #8   IP: 47.142.140.156
Old 06-07-2021, 02:12 AM
JOHN COOKSON JOHN COOKSON is offline
Afourian MVP, Professor Emeritus
 
Join Date: Nov 2008
Posts: 3,500
Thanks: 54
Thanked 855 Times in 629 Posts
WHAT 'YA THINK?

Quote:
Originally Posted by Mo View Post
Hi
Sure sounds like it shifted. I just need to figure out if I damaged anything in the reversing gear. Right now it's not bad but I'd hate to be out on a little excursion and something deteriorate.
Any thoughts on bearings within the reversing gear that might have gotten damaged or worn?
Mo
Maybe check the engine mounts for tightness every so often for awhile? Should help for some peace of mind.

ex TRUE GRIT
Reply With Quote
The Following 2 Users Say Thank You to JOHN COOKSON For This Useful Post:
Mo (06-07-2021), TimBSmith (06-08-2021)
  #9   IP: 108.51.19.207
Old 06-08-2021, 01:16 AM
svsonora svsonora is offline
Senior Member
 
Join Date: Sep 2020
Location: Washington DC area
Posts: 22
Thanks: 1
Thanked 8 Times in 3 Posts
This sounds silly but did you use the same length of bolt as the ones that came out of the coupling? My bolts were touching the rear of the transmission box and every time i tightened it up, my shaft would lose alignment. When I went to shorter bolts, they did not touch and the surfaces mated properly.
__________________
1975 Bristol 30 Sonora del Viento
Reply With Quote
Reply

Thread Tools
Display Modes

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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Shaft centering cones tenders The Wish List 7 12-31-2020 07:40 AM
Shaft back in, how worried should I be about alignment JimF Drive Train / Propellers 9 06-23-2016 09:24 PM
Prop shaft coupler to trans flange rubber vibration damper gspeckma Drive Train / Propellers 16 12-24-2013 03:15 PM
Run Out Shaft Vibration dvd General Interest 6 12-11-2009 11:07 AM
shaft or transmission vibration dvd Drive Train / Propellers 14 12-20-2008 02:59 PM


All times are GMT -4. The time now is 05:50 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.


Universal® is a registered trademark of Westerbeke Corporation

Copyright © 2004-2024 Moyer Marine Inc.

All Rights Reserved