Bellow condition??

Wave34

Petty Officer 1st Class
Joined
Oct 17, 2017
Messages
360
My boat is used in fresh water 99.9% of the time and is stored on the trailer when not boating with the outdrive lowered to make the below straight.

I want to know if the condition of the bellow is bad or normal.
Rubber seems dry a bit and I can see a shallow crack.

The new Volvo bellow are hard plastic compared to this one that is all rubber.
Are they better?
I never changed it since I bought the boat 8 years ago.
 

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Kosmofreeze

Seaman
Joined
Aug 23, 2023
Messages
54
My DP-SM bellows were last changed in 2011. My boat is dry stored (fresh water only, trailered and inside) when not in use. It saw about 200 hours use in 24 years. I changed both bellows this spring. If you are handy with tools, don't sweat pulling the drive - watch some youtube vids - it's not bad at all. My 24 year old bellows (soft rubber) still looked new - no evidence of cracking. I wonder if the new hard plastic design will last as long as the old soft rubber design ... I hope so.
 

Scott06

Admiral
Joined
Apr 20, 2014
Messages
7,241
My DP-SM bellows were last changed in 2011. My boat is dry stored (fresh water only, trailered and inside) when not in use. It saw about 200 hours use in 24 years. I changed both bellows this spring. If you are handy with tools, don't sweat pulling the drive - watch some youtube vids - it's not bad at all. My 24 year old bellows (soft rubber) still looked new - no evidence of cracking. I wonder if the new hard plastic design will last as long as the old soft rubber design ... I hope so.
I had similar experince with my merc alpha gen 2 I changed them at 18 years as they were just stating to get real stiff. Never leaked. Use OEM bellows they last.

since I planned to keep the boat no sense getting the last year or two out of them. If these ones last 15 years it’s someone else problem.
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
13,472
I have found that the older all rubber (if OEM) Cobra/Volvo SX bellows (same part I think) lasts about 10 years before you start seeing cracks in the folds. I last did mine in 2016. So maybe this spring, I have two spares in the garage lol. Like everything else for the Cobra.
Think about it, it's like a tire. Would you leave trailer tires on your trailer that look like the pix of the bellows above? Same issue and same potential bad outcome!
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,668
The problem is...if they do leak, you are going to possibly have thousands of dollars of damage as the water in the bellows will get into your drive as well as possibly sink your boat.

Cheap insurance to replace the u-joint bellows every 5 years or so...per DonS(RIP).
 

Wave34

Petty Officer 1st Class
Joined
Oct 17, 2017
Messages
360
My DP-SM bellows were last changed in 2011. My boat is dry stored (fresh water only, trailered and inside) when not in use. It saw about 200 hours use in 24 years. I changed both bellows this spring. If you are handy with tools, don't sweat pulling the drive - watch some youtube vids - it's not bad at all. My 24 year old bellows (soft rubber) still looked new - no evidence of cracking. I wonder if the new hard plastic design will last as long as the old soft rubber design ... I hope so.
I also have a SP-SM with a soft rubber bellow. I watched many videos, and it seems that the new Volvo bellow is made of hard plastic, and that it is not possible to insert it in the opening, and the drive and 'pivot support' (I don't know the name) need to be removed.

Did you have a hard rubber bellow installed and did you disassembled parts?
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
13,472
Even with the soft rubber version it’s better to remove the pivot housing to make sure that you have the gimble housing end of the bellows properly seated on that flange.
Also removing the bolts for the pivot housing helps with then not getting seized up. On the Volvo you’d have to disconnect the shift cable & then reconnect & adjust it. On the Cobra because the shift cable set up is different that’s not necessary….
 
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Kosmofreeze

Seaman
Joined
Aug 23, 2023
Messages
54
I also have a SP-SM with a soft rubber bellow. I watched many videos, and it seems that the new Volvo bellow is made of hard plastic, and that it is not possible to insert it in the opening, and the drive and 'pivot support' (I don't know the name) need to be removed.

Did you have a hard rubber bellow installed and did you disassembled parts?
While it might be possible to replace the bellows without removing the pivot housing, removing it makes it much easier to access. When removing the pivot housing break the female allen head bolts loose BEFORE you pull the drive. The weight of the drive will help you break those suckers loose as the pivot housing tends to pivot when wrenching on them.
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
13,472
I'm not sure about the Volvo but the Cobra gimble housing has a groove in it and the bellows has a ridge in the sealing surface, that ridge has to go in the groove and the clamp has to have the screw end properly positioned so it doesn't cut the new bellows. All that is easier with the pivot housing out of your way. With the Volvo the only other thing is you have to disconnect the retainer for the shift cable and then replace and adjust it when you're done. With the Cobra its a bit different because the shift cable design is different, I can disconnect it up at the engine shift bracket and that gives enough slack in the cable to pull the pivot housing back far enough.
Here's a pic of the Cobra bellows, see if the one for the Volvo has the same ridge. Cobra bellows ridge.jpg
 
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