Sign in to follow this  
Followers 0
fredthenuke

Shep and others have mentioned

10 posts in this topic

Shep and others have mentioned that the sterndrive bellows keeps a boat from sinking - as in a ruptured bellows would allow water to enter the engine compartment. My question is simple - is this the case in all models of sterndrives or only certain ones?

I ask because when a muskrat ate a hole in my starboard Volvo XDP bellows (a rather big one clean through) the bellows filled with water and I had some minor rust on the gimbal bearing. But not a DROP of water in the engine compartment.

Of course bellows and gimbal were replaced (at a very high deer cost but that is boating). But why did I not have engine compartment water intrusion? Is it an XDP design difference? I know from the exploded parts view on www.marinepartsexpress.com that my transom housing seems to have seals forward of the gimbal bearing - that may be why but I'm not sure.

specifically if you go to the schematics for volvo on that website and click on marine drive and transmission and then XDP-B and then transmissions and then transom shield.pdf - part 15 is a seal and part 16 is a rubber element. 17 is the gimbal bearing. 18 is the bearing plate.

Share this post


Link to post
Share on other sites

i believe bellows sinking a boat are Mercruiser related issues as their design is different than Volvo which does not have similar catastrophe's when the bellows fail.

Share this post


Link to post
Share on other sites
I ask because when a muskrat ate a hole in my starboard Volvo XDP bellows (a rather big one clean through) the bellows filled with water and I had some minor rust on the gimbal bearing. But not a DROP of water in the engine compartment.

Sounds like its time for some payback. varmint hunting!!

untitled-1.jpg

:pirate:

Share this post


Link to post
Share on other sites

Ir it had been a Merc that had the problem the boat would of had water in the bilge. With that said, muskrats only chew on Volvos! :tofunny:

Share this post


Link to post
Share on other sites

Why do you mind muskrats?

miss-muskrats.jpg

I would let them on my Volvo anytime. ;):lol:

Share this post


Link to post
Share on other sites

Fred:

Volvo drives are designed with transom seals that prevent water from leaking into the bilge when the bellows fails. I can attest to the fact that they do work, as I have had three failures of the bellows on my XDP drives (one bad enough to require a complete drive replacement), and not one drop of water was in the bilge. The only way I knew that there was a hole in the bellows is when the water got into the drive oil the oil in the drive resevior truned milky.

If you have a Mercruiser, you are not that lucky. None of the bellows have transom seals live Volvo, and one tear in a Mercruiser belloows can sink a boat. On my last boat with a Bravo II drive, I had a shift cable bellows incorrctly replaced, and there was a pretty good amount of water in the bilge. Good thing it was a slow leak, not a failure. Had to pull the boat, and redo the shift bellows.

Share this post


Link to post
Share on other sites

That explains my dry bilge... The only reason I found the muskrat hole was I had the boat out for drive oil and was removing the top drive cover to inspect the upper zinc. If I had skipped the zinc inspection I had no reason to be looking that high up on the drive and would not have saw the hole... Until I heard the gimbal bearing grinding from being rusted out (which could take months or more on a freshwater lake). The hole could have been there for months before I found it (and probably was).

Share this post


Link to post
Share on other sites
That explains my dry bilge... The only reason I found the muskrat hole was I had the boat out for drive oil and was removing the top drive cover to inspect the upper zinc. If I had skipped the zinc inspection I had no reason to be looking that high up on the drive and would not have saw the hole... Until I heard the gimbal bearing grinding from being rusted out (which could take months or more on a freshwater lake). The hole could have been there for months before I found it (and probably was).

We don't seem to have muskrats around here. Not sure why that is. Maybe it is too dang hot for them or maybe something is getting them.

Here is a little something on Muskrats

Share this post


Link to post
Share on other sites
We don't seem to have muskrats around here. Not sure why that is. Maybe it is too dang hot for them or maybe something is getting them.

Here is a little something on Muskrats

And now that song will be in my head for the rest of the day. :pirate:

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0