Reply
 
Thread Tools Display Modes
 
Old 11-18-2013, 03:42 PM   #1
Veteran Member
 
tiku's Avatar
 
City: Espoo
Country: Finland
Vessel Name: Carpe Diem
Vessel Model: Storebro 34
Join Date: Nov 2012
Posts: 74
Bent strut and drive train maintenance

Hi!

I decided to tackle some drive train maintenance this haul-out season. On the to do list are:

-changing stuffing box hoses
-dealing with bent strut
-replace strut bearings
-etc...

I ran into a problem with my port engine and more specifically with the strut. As you can see the axle is not really in the center and the bearing has worn quite heavily.



Another clue as to something is wrong is where the axle enters the hull. There is an area, roughly 10 cm long where I have nice shiny metal. In other words the axle is touching the hull. Lightly but still, it's not right.

The props are off (it was another battle, read more from the blog) and the starboard strut is fine and the bearing shows no uneven wear but I'll change it anyway.

Tonight I disconnected the coupling from the transmission and I was wondering if the axle is going to shoot to some direction due to the bent strut but no, it seems to be dead on.



As you can see, we are talking about picture perfect alignment here.



So this leads me to wonder how is it possible? The strut is bent, I can see it with my eyes and the axle is eating into the strut bearing but still the coupling end shows no misalignment and during the season there were no vibrations.

Should I proceed with the strut? Drop it off and have it straightened or buy a new one? Or am I killing the drive train softly if I just reassemble it "as is" after doing the maintenance.

Logic says to go the long way, but I'm wondering why the axle is not showing any misalignment in the coupling end?

To my knowledge there is no bearing in the "axle tube" and my stuffing boxes are of the hose type so they don't really offer support...
__________________
Advertisement

__________________
Storebro 34 Royal Cruiser - 1969
Twin Volvo Penta Tamd 40b with shafts
www.storebro34rc.blogspot.fi
tiku is offline   Reply With Quote
Old 11-18-2013, 04:02 PM   #2
TF Site Team
 
Larry M's Avatar
 
City: JAX, FL
Country: USA
Vessel Name: Hobo
Vessel Model: Krogen 42-120
Join Date: Nov 2008
Posts: 5,740
Have you pulled the shaft to make sure that it is straight? And how does the shaft look at the front of the strut/cutlass bearing? I'd pull the shaft then do an alignment check with string or laser from the coupler through the strut.

We had a bent strut on our sailboat. It was easier/cheaper to repair than to replace since a replacement would have to be cast.
__________________

Larry M is offline   Reply With Quote
Old 11-18-2013, 04:10 PM   #3
Veteran Member
 
tiku's Avatar
 
City: Espoo
Country: Finland
Vessel Name: Carpe Diem
Vessel Model: Storebro 34
Join Date: Nov 2012
Posts: 74
Not yet, the coupling flange is waiting for tomorrow in a bath of release oil. It was enough trouble today to punch out the locking pin, undo the bolts and get the flanges separated. I will drop the shaft anyway and have a closer look at it.

To me the front of the strut/bearing does not look as bad as the rear, I will get a better look when the shaft is out. It's just that I was so sure that there would be a huge misalignment issue, but no....

In case anyone is wondering, in Volvo's setup the pin goes through the axle and can be punched out with a 6mm punch...
__________________
Storebro 34 Royal Cruiser - 1969
Twin Volvo Penta Tamd 40b with shafts
www.storebro34rc.blogspot.fi
tiku is offline   Reply With Quote
Old 11-18-2013, 04:40 PM   #4
Senior Member
 
obthomas's Avatar
 
City: Seabrook Texas
Country: USA
Vessel Name: TheVenture
Vessel Model: 1985 Bestway Labelle Sundeck 40ft
Join Date: May 2013
Posts: 462
Use a spacer just smaller in diameter than the shaft and recouple the flanges with longer bolts and make up the bolts and press the shaft out of the coupling.
obthomas is offline   Reply With Quote
Old 11-18-2013, 04:51 PM   #5
Scraping Paint
 
City: Fort Lauderdale
Vessel Model: CHB 48 Zodiac YL 4.2
Join Date: Oct 2007
Posts: 3,804
Quote:
Originally Posted by obthomas View Post
Use a spacer just smaller in diameter than the shaft and recouple the flanges with longer bolts and make up the bolts and press the shaft out of the coupling.
Another word for spacer is socket.
RickB is offline   Reply With Quote
Old 11-18-2013, 06:05 PM   #6
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 15,903
just because the shaft is aligned with the motor doesn't mean a thing if everything is not in the right place for the struts, stuffing tube, etc....

First line everything up roughly then before aligning the engine...see just how much resistance is on the shaft from the cutlass bearings...if a lot...then the strut may have to be realigned.
psneeld is online now   Reply With Quote
Old 11-19-2013, 12:16 AM   #7
Guru
 
C lectric's Avatar
 
City: Somewhere
Country: , Canada
Vessel Name: Island Pride
Vessel Model: Palmer sedan 32'
Join Date: Oct 2007
Posts: 1,872
Also get the shaft itself checked. It could have a small bend from whatever bent the strut. Maybe not but find out.
C lectric is offline   Reply With Quote
Old 11-28-2013, 08:16 AM   #8
Senior Member
 
City: Green Cove Springs, Florida
Country: USA
Join Date: Feb 2012
Posts: 210
Send a message via Skype™ to bglad
You may be able to use a large pipe wrench to straighten the strut into alignment so when you install a new bearing it won't be in a bind. Before you do too much you need to make sure you can put the engine where it needs to go after you realign the strut and propeller shaft in the hull. Aligning the prop shaft in the log is nice but doesn't really help anything. Especially if the engine can't be moved to mate up with the shaft coupling without hitting the hull bottom, stringer or deck.
bglad is offline   Reply With Quote
Old 11-28-2013, 09:08 AM   #9
Guru
 
Tom.B's Avatar
 
City: Cary, NC
Country: USA
Vessel Name: Skinny Dippin'
Vessel Model: Navigator 4200 Classic
Join Date: Jul 2009
Posts: 5,153
We are doing much of the same maintenance this winter too. We have already diagnosed a bent shaft and we plan on a complete replacement. I certainly wouldn't say that a bent strut isn't the problem, but IMHO, that's a pretty hefty piece. If you have yet to do it, you might want to have a pro come help you diagnose it before you start going at it with brute force.
__________________
2000 Navigator 4200 Classic
(NOT a trawler)
Tom.B is offline   Reply With Quote
Old 11-28-2013, 09:32 AM   #10
Guru
 
Forkliftt's Avatar
 
City: Biloxi Mississippi
Country: USA
Vessel Name: Patricia Louise II
Vessel Model: 1983 42' Present Sundeck
Join Date: Oct 2007
Posts: 2,433
Great approach

Quote:
Originally Posted by obthomas View Post
Use a spacer just smaller in diameter than the shaft and recouple the flanges with longer bolts and make up the bolts and press the shaft out of the coupling.
Sounds like an easy way to get the coupling off of the shaft. Why not temporarily refasten coupler to marine gear and rotate by hand while watching shaft at the strut?
__________________
Steve Point Cadet/ Biloxi, Mississippi USA
*Present 42 twin 135 Lehmans
Forkliftt is offline   Reply With Quote
Old 11-28-2013, 09:44 AM   #11
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Country: Bumpkin?
Join Date: Oct 2007
Posts: 9,996
Greetings,
Mr. tiku. I fully agree with Mr. Tom B. regarding not using brute force (Large pipe wrench-Mr. bglad's suggestion) to straighten your strut. Go gently my brother. It could very well be that a professional WILL use brute force but if any damage to the hull or fasteners is done it will be the pro's responsibility NOT yours. Maybe a course of action would be to remove the offending strut and use some sort of hydraulic press to straighten. So, when you stuff your strut you can strut your stuff.
__________________
RTF
RT Firefly is online now   Reply With Quote
Old 11-28-2013, 09:49 AM   #12
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 15,903
Quote:
Originally Posted by Forkliftt View Post
Sounds like an easy way to get the coupling off of the shaft. Why not temporarily refasten coupler to marine gear and rotate by hand while watching shaft at the strut?
Easy until you bend or break the flange on the back of the tranny...that's expensive unless you repair it yourself.

I always recommend cut off a solid coupling if it doesn't come off easy without too much force...and replace with a split coupling. Requires a machine shop to do but they check your shaft for being straight also.
psneeld is online now   Reply With Quote
Old 11-28-2013, 10:16 AM   #13
Senior Member
 
City: Green Cove Springs, Florida
Country: USA
Join Date: Feb 2012
Posts: 210
Send a message via Skype™ to bglad
You certainly wouldn't be wrong to hire a "pro" but the parts are fairly light weight and the amount of force required to love them back in shape may likely be less than you think. I base my assessment of the equipment size by the fact it is a VP cone clutch transmission, four bolt coupling flange and guessing 1.5" shaft. The strut barrel is not much larger than the shaft so relatively light. I wasn't figuring the force required would fall into the "brute" category.
__________________

bglad is offline   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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 11:15 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012