Reply
 
Thread Tools Search this Thread Display Modes
 
Old 06-04-2012, 09:15 PM   #1
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Vessel Name: Carquinez Coot
Vessel Model: penultimate Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 12,559
Clunk ... Aaahh! ... Crunch

Went out for a three-hour cruise in Carquinez Strait today to exercise the JD, with the benefit of a seal swimming in Mare Island Strait paying no attention to us and the "neighborhood" trawler collecting fish bait, as well as an eagle catching a fish in Carquinez Strait.

Well, entering my berth at the Vallejo Marina, about three-quarters in, I shifted from neutral to reverse to check forward momentum. Then CLUNK, the sound of metal hitting metal! The shift to reverse had no effect, so the 14-ton Coot hit the dock. No damage as speed was slow. Boy, do I have an attentive Guardian Angel! Hate to think it could have happened elsewhere.

After inspection, I found the cause. Can you all propose/guess the cause of my dilemma?
__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 06-04-2012, 09:21 PM   #2
Guru
 
Steve's Avatar
 
City: Thibodaux, Louisiana
Vessel Name: Gumbo
Vessel Model: 2003 Monk 36
Join Date: Oct 2007
Posts: 3,882
prop came loose? shift cable broke or came off
Steve W
Steve is offline   Reply With Quote
Old 06-04-2012, 09:33 PM   #3
Guru
 
HopCar's Avatar
 
City: Miami Florida
Vessel Name: Possum
Vessel Model: Ellis 28
Join Date: Aug 2011
Posts: 5,307
I had a similar experience in my ill spent youth. Clunk, bam, and the rudder locked. Yup, broken prop shaft. How about you?
HopCar is offline   Reply With Quote
Old 06-04-2012, 09:35 PM   #4
Guru
 
swampu's Avatar


 
City: Biloxi, MS
Vessel Name: Cajun Rose
Vessel Model: Biloxi Lugger
Join Date: Jul 2011
Posts: 1,384
Probably the shaft broke and the prop and what was left of the shaft slid back to the rudder. Lots of years of fishing string and crab trap yellow line build up.
swampu is offline   Reply With Quote
Old 06-04-2012, 09:35 PM   #5
Guru
 
HopCar's Avatar
 
City: Miami Florida
Vessel Name: Possum
Vessel Model: Ellis 28
Join Date: Aug 2011
Posts: 5,307
If the shaft didn't break, did it pull out of the engine coupling?
HopCar is offline   Reply With Quote
Old 06-04-2012, 09:36 PM   #6
Guru
 
swampu's Avatar


 
City: Biloxi, MS
Vessel Name: Cajun Rose
Vessel Model: Biloxi Lugger
Join Date: Jul 2011
Posts: 1,384
Quote:
Originally Posted by HopCar View Post
I had a similar experience in my ill spent youth. Clunk, bam, and the rudder locked. Yup, broken prop shaft. How about you?
Damn you type faster than me.....
swampu is offline   Reply With Quote
Old 06-04-2012, 10:01 PM   #7
Guru
 
HopCar's Avatar
 
City: Miami Florida
Vessel Name: Possum
Vessel Model: Ellis 28
Join Date: Aug 2011
Posts: 5,307
Swampu, great minds think alike, but I bet we're both wrong.
HopCar is offline   Reply With Quote
Old 06-04-2012, 10:05 PM   #8
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Vessel Name: Carquinez Coot
Vessel Model: penultimate Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 12,559
You're getting very close. Will answer this evening (PDT).
__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 06-04-2012, 10:13 PM   #9
Guru
 
Conrad's Avatar
 
City: Campbell River
Vessel Name: Blue Sky
Vessel Model: Nordic Tugs 42 Hull #001
Join Date: Oct 2007
Posts: 1,972
Key come out of the keyway?
__________________
Conrad
Berthed in
Campbell River BC
Conrad is offline   Reply With Quote
Old 06-04-2012, 10:17 PM   #10
Guru
 
refugio's Avatar
 
City: Meydenbauer Bay Yacht Club
Vessel Name: Lulu (Refugio sold)
Join Date: Mar 2012
Posts: 1,284
I can't imagine you broke the shaft at idle...I don't know what your drive train looks like...coupling bolts?
refugio is offline   Reply With Quote
Old 06-04-2012, 11:35 PM   #11
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Vessel Name: Carquinez Coot
Vessel Model: penultimate Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 12,559
OK. Here it is.

A two-foot section of the propeller shaft, connecting the transmission with the remainder of the shaft, came apart SIMULTANEOUSLY at both forward and aft universal joints. Glad it didn't come apart at just the aft end, resulting in the shaft section whipping about.

The shaft, it's gone!



The shaft section was "resting" on top of the hull. Here I've placed it along the shaft astern.

__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 06-05-2012, 12:28 AM   #12
Senior Member
 
Baggiolini's Avatar
 
City: Monterey, CA
Vessel Name: Mahalo
Vessel Model: Defever 44
Join Date: Jun 2011
Posts: 406
Mark, you're a lucky boy that it happened when it did!
Baggiolini is offline   Reply With Quote
Old 06-05-2012, 12:33 AM   #13
Guru
 
HopCar's Avatar
 
City: Miami Florida
Vessel Name: Possum
Vessel Model: Ellis 28
Join Date: Aug 2011
Posts: 5,307
Scary stuff. How about a close up photo of the point of failure?
HopCar is offline   Reply With Quote
Old 06-05-2012, 01:03 AM   #14
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Vessel Name: Carquinez Coot
Vessel Model: penultimate Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 12,559
Quote:
Originally Posted by Baggiolini View Post
Mark, you're a lucky boy that it happened when it did!
Yes! Thanks to my Guardian Angel!
__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 06-05-2012, 01:04 AM   #15
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Vessel Name: Carquinez Coot
Vessel Model: penultimate Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 12,559
Quote:
Originally Posted by HopCar View Post
Scary stuff. How about a close up photo of the point of failure?
Looks like all of the devices holding the universal joints together came "unattached."
__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 06-05-2012, 03:46 AM   #16
Scraping Paint
 
City: -
Join Date: Oct 2007
Posts: 13,745
If you find out what caused this-- poor manufacturing, substandard material, defective casting or machining-- it would be interesting to know. Seems an odd occurance on a brand new boat. Or did fasteners simply loosen up and fall out? If they did I assume they were not safety wired?

I'm writing this from the Delta airport lounge at Narita on our way to Beijing for a couple of weeks. So since we're on the other side of the dateline I guess I'll get your response before you write it.
Marin is offline   Reply With Quote
Old 06-05-2012, 05:54 AM   #17
Guru
 
psneeld's Avatar
 
City: Ft Pierce
Vessel Name: Sold
Vessel Model: Was an Albin/PSN 40
Join Date: Oct 2011
Posts: 28,149
interesting we were just discussing this very same setup in another thread....I'm guessing the same setup that reduces vibration.

one view of safer boating is that boats should be as uncomplicated as possible to keep failures at a minimum and others believe that some complication reduces failure (both mechanical and human) to a degree.

here's an example of good workmanship to a point (install) and I'm sure good maintenance and routine observation of gear...but yet.. a what I would guess is a VERY uncommon failure happened...probably up there with getting hit by lightning.

so the debate will continue...neanderthal for reducing failures...or material progress for making boating incrementally easier, safer, more enjoyable, etc...etc

Thank you for the post Mark...this is where forums shine as it is info that is rarely heard )even better seen) from manufacturers, dealers, "experts", etc.

I'm eagerly awaiting the "why" it happened for the back of my mind, boating hard drive.
psneeld is online now   Reply With Quote
Old 06-05-2012, 06:18 AM   #18
TF Site Team
 
City: Ex-Brisbane, (Australia), now Bribie Island, Qld
Vessel Name: Now boatless - sold 6/2018
Vessel Model: Had a Clipper (CHB) 34
Join Date: Jun 2008
Posts: 10,101
That sort of coupling with thrust bearing arrangement, which is great at preventing vibration, v's the old straight shaft arrangement most of us have, really shouldn't come apart any more than one would expect the tail/drive shaft on your car to do so. Less likely, in fact, as subjected to much less speed variation and intermittent stress. It looks like all the bolts in the two universal joints came out at once. However, in all probability they have been loosening for some time, then one came out altogether causing enough stress to account for the others rather more quickly. Still - should not have happened. Especially on a near new boat. Guess who is going to become the most paranoid checker of his prop shaft universals in the boating world from here on in....?
Peter B is offline   Reply With Quote
Old 06-05-2012, 06:45 AM   #19
Guru
 
jleonard's Avatar
 
Join Date: Jun 2008
Posts: 5,037
I'd like to see some close up pictures of the failed parts. I designed and manufactured steering shaft u joints for 25 plus years and failures like that are rare.
__________________
Jay Leonard
Ex boats: 1983 40 Albin trunk cabin, 1978 Mainship 34 Model 1
New Port Richey, Fl
jleonard is offline   Reply With Quote
Old 06-05-2012, 06:57 AM   #20
Scraping Paint
 
City: Fort Lauderdale
Vessel Model: CHB 48 Zodiac YL 4.2
Join Date: Oct 2007
Posts: 3,804
Quote:
Originally Posted by markpierce View Post
Can you all propose/guess the cause of my dilemma?
That assembly is a Cardan shaft. It appears that the pin retainers loosened or were never tightened properly when installed and were probably missing for some length of time until one moved out enough to create sufficient vibration to throw both out.

My guess is that the engine end pin left the scene first and the clunk you heard was the prop flinging the shaft around which caused the aft pin to depart. If it happened in the reverse order you might have had an even more exciting adventure.

This is a case study in why "checking" moving parts means to actually look at them and move them to make sure all the bits are in place and fastened properly.
RickB is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 06:44 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012