Can bilge water get into the pds bearings and upper outdrive?

[boating maniac]

So I know their is a seal around the transom shield on the outside, but what about bilge water getting into the flywheel housing u joint area from the inside of the boat? Is their an oring to seals off the u joints?

 

[saaristo]

My understanding is that it can, havent taken it apart yet but looking from behind of the engine it seems to me it's an open end.

 

[alldodge]

So I know their is a seal around the transom shield on the outside, but what about bilge water getting into the flywheel housing u joint area from the inside of the boat? Is their an oring to seals off the u joints?

While its not impossible to get water from the bilge into the U joint area, it real close to impossible. If water is high enough to splash in, then the starter is under water. The water would have to make it past the gimbal bearing and drive shaft to get to the bellows.

In other words, if you have water in the U joint bellows, you have a leak in the bellows or drive

 

[boating maniac]

The opening is only like 5" above the bottom of the bilge. So once you come up on plane won't it splash into the opening?

 

[alldodge]

Not seeing a drive shaft being only 5 inches, the oil pan is generally a bit more then that and its not sitting on the bottom.

What motor is it?

In any case, the pic below is an Alpha and your in the VP section, but distances are the same, because the VP and Merc uses the same key hole cut out, and the same motors, mostly

In the pic, the first hole is the exhaust, the next is the gimbal bearing. Once the drive shaft has o rings which fit inside the bearing when installed. Now the drive shaft and center of the bearing is sealled, so only way for water to get in, is thru the bearing itself

 

[boating maniac]

So there is an oring on each side of the bearing sealing it? I know on the Volvo they use open bearings.

 

[alldodge]

The o rings are just on the inside of the center of the gimbal. In link below this is a VP drive shaft and note to 2 grooves close to the U joint. Those grooves get o rings prior to install

https://www.ebay.com/i/303194142019...QEu-WsyyF4I1GcQoBd1zFE4RVQc6pRDBoCZoUQAvD_BwE

 

[boating maniac]

I have the older style pds bearings with the inner and outer bearings in the flywheel housing. I watched a YouTube video and it has open bearings and it looks like each bearing has an external seal. Or is that just a dust seal?

 

[Scott Danforth]

No, bilge water cant get in the PDS bearings unless water was over the crank on the motor

Most of the time, a leaking bellows is the culprit

There are seals and open bearings

here you go on the process for changing bearings.

https://forums.iboats.com/forum/eng...s-engines-outdrives/10343318-pds-shaft-issues

 

[boating maniac]

So the seals are good enough to keep out splashing bilge water, just not solid water filled completely like in the case of a bellows failure? I saw a youtube vid that showed seals on both sides, but I'm not sure about a seal for the joints. Or are the u joints okay with splashing bilge water?

 

[alldodge]

U joints can be compromised with water. Pump some new grease in them and see if any water comes out

 

[boating maniac]

I see. I'm just trying to prevent any future issues. I'm totally repowering the boat, so the ujoints and pds bearings will be new.

 

[Scott Danforth]

I see. I'm just trying to prevent any future issues. I'm totally repowering the boat, so the ujoints and pds bearings will be new.

then make sure to pull the drive or at a minimum pull the upper every year to inspect the u-joints and replace the bellows every few years (VP recommends every 2 years)

 

[jerryjerry05]

The 2 seals on each side of the bearings are grease shields, keeping the grease in the PDS cavity.

You'd have to be close to sinking for water to get that far into the housing.