Bellow condition??

Wave34 · Saturday at 8:48 AM

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.

flashback · Saturday at 9:04 AM

if it were me i would change it...

Lou C · Saturday at 9:11 AM

Definitely change it, the cracks mean the rubber is getting oxidized and dried out and isn’t far from failure

Scott Danforth · Saturday at 9:53 AM

Change them

airshot · Saturday at 10:45 AM

If your questioning it....it needs to be changed...sooner rather than later !

Wave34 · Saturday at 1:38 PM

OK thanks guys.
I will change it.

bruceb58 · Saturday at 5:05 PM

I changed my Volvo bellows every 6 years on DonS's recommendation from many years ago before he passed.

Kosmofreeze · Sunday at 6:47 AM

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 · Sunday at 8:21 AM

Kosmofreeze said:
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 · Sunday at 8:53 AM

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 · Sunday at 10:19 AM

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).

bruceb58 · Sunday at 10:23 AM

Lou C · Sunday at 10:52 AM

And….use OEM parts!

Wave34 · 2025-10-08T13:05:27-0600

Kosmofreeze said:
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 · 2025-10-08T15:01:11-0600

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….

tpenfield · 2025-10-08T15:14:47-0600

@Wave34 . . . the sight of your bellows makes me feel a whole lot better about the ones on my boat.

Those bellows scream borrowed time.

Bellow condition??

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