Bellows full of grease/oil

[Oskarol]

Hi all, I have a new this season to me 1997 four winns 5.7 with volvo penta C1 outdrive (prod num 3868388).

Pulled the drive today after winterizing the engine and found the bellows to be full of a milky, grease/oil. The stuff is very thick, non flowing. This was also on the ujoints and the gimbal bearing, but past the gimbal was totally clean and dry.

The gear oil level in the outdrive seems ok, no obvious loss of level, no milk at all. And I can see the thicker bearing grease (greenish) that was pumped into the gimbal by the previous owner. Gimbal seems fine, smooth and so do the ujoints. Anyone see this before?

 

[Grub54891]

Yeah, You have a water leak getting into the bellows, mixing with the grease that was in there and making a mess. I'm sure the gimble will fail soon, along with the u-joints. They now have water in them.

 

[Oskarol]

Thanks for the reply. Do you think this could be drive oil leaking past the drive shaft seal or just leftover grease in there? It isn't really flowable and definitely seems more like grease than oil.

 

[Grub54891]

If the drive oil is clean/not milky, or going low, then it's not leaking. If any of the above are present, then yes. The water is mixing with the grease.

 

[Horigan]

If it was me, I would pressure test the drive to confirm the input shaft seal is not leaking.

 

[Lou C]

yep I'd figure on at least changing the gimble bearing, if this was fresh water you may be able to pump out the milky grease from your u joints, if you see rusty grease coming out of them though they should be replaced. You do not want a u joint failure on an I/O that can cause catastrophic failure. Any new to the owner I/O boat should have the drive pulled, pressure tested, bellows inspected and replaced if any doubt to its condition as well as checking the gimble bearing and u joints. People who own these often do not pull the drive yearly like you are supposed to. If you get in the habit of doing that while yes it can be a pain unless you are set up for it (drive jack & alignment tool) you can make your sterndrive last a really long time by doing these simple jobs.
Changing the bellows on these is not a hard job, as long as the pivot housing hinge bolts are not seized up. I lube mine with OMC gasket sealer and use that on all the bolts on the drive and transom mount. When you check the bellows as a maintenance item, look closely with a bright LED flashlight you are looking for small cracks in the folds. When you see those its time even if its not leaking. I have found that the OE bellows on a Cobra or SX can last as long as 10 years before cracks appear but your experience may vary depending on if you can keep the drive down in storage, that makes it last longer.

 

[Oskarol]

Thanks for the feedback. Definitely cracks in the bellows but not seeing a clear hole. Have ordered what I need to pressure test the drive. Will also change gimbal, ujoints and bellows while I'm in there.

On that note, I am struggling to understand how the sterndrive seals against the bellows. The old bellows has 4 indents which match up with the grooves on the drive. The new bellows I ordered (part number 21752712, which I believe is the right one for an SX-C1 (AQ)) does not have the same indents. Was there a design change? Is my understanding that this is a critical sealing point correct to keep water out?

You can see a pic of the grooves I the pics I posted above. Here is a pic of the sterndrive bell and sealing surface, which I will need to figure out how to clean up.

 

[tank1949]

Thanks for the reply. Do you think this could be drive oil leaking past the drive shaft seal or just leftover grease in there? It isn't really flowable and definitely seems more like grease than oil.

Not 100% on Volvos but you should buy a pressure testing kit and find leaks before your really ruin something. Too much gimbal or u joint grease will sling out and become messy. The water and lube messs raises major concerns.

 

[Horigan]

Thanks for the feedback. Definitely cracks in the bellows but not seeing a clear hole. Have ordered what I need to pressure test the drive. Will also change gimbal, ujoints and bellows while I'm in there.

On that note, I am struggling to understand how the sterndrive seals against the bellows. The old bellows has 4 indents which match up with the grooves on the drive. The new bellows I ordered (part number 21752712, which I believe is the right one for an SX-C1 (AQ)) does not have the same indents. Was there a design change? Is my understanding that this is a critical sealing point correct to keep water out?

You can see a pic of the grooves I the pics I posted above. Here is a pic of the sterndrive bell and sealing surface, which I will need to figure out how to clean up.

There are no indents on the seal. It seals against the forward edge of the bell. Clean it up with a scotchbrite pad, apply some triple guard grease, and it will seal fine. There is a fair bit of rubber compression when you tighten the six nuts that attach the drive.

 

[Monterey296Twin5.0Gi]

There are no indents on the seal. It seals against the forward edge of the bell. Clean it up with a scotchbrite pad, apply some triple guard grease, and it will seal fine. There is a fair bit of rubber compression when you tighten the six nuts that attach the drive.

We definitely scratched out head at the 4 indents too. It really seemed like a water intrusion point when we saw them and that our bellows didn't have obvious holes. Even the front lip of the bell has the indents, so if it does seal it is essentially a knife edge seal. Even with some compression it seems like the indents would still allow water into the bellows. We just had to have faith that it was designed this way and trust VP and our mechanic.