Catalina 350 International Association

While doing an oil and filter change, I noticed the hose going to the PSS seal had a bulge in it and decided to replace it. After replacing the hose, the PSS seal now sprays water all over when the prop is engaged. I've tried "burping" the seal to clean out any debris to no improvement. There is no leakage when the prop is not engaged. I suspect the new hose may be stiffer than the old hose and create some side load on the carbon seal that creates the leak. Any suggestions as to how to clean or align the carbon seal?

Thanks

Gary & Janet,

I took your question and ran it through the Gemini.Google AI.

Here is a link to its response; https://gemini.google.com/share/ac869d092bd8

Bill

Thanks for the response. That was very helpful and confirmed my suspicion.
The new hose was significantly stiffer than the old hose. ($3 fuel line from Ace Hardware). I bought a more flexible marine grade hose for $12 that had the same problem. It appears the old hose has taken a set that does not apply any side load or a spring load in the opposite direction of the bellows spring load. I eventually put the old hose back on. Even though it may have a bulging exterior, it is not under pressure and likely to burst.

I suspect I might be able to create more spring load by compressing the bellows slightly, but given the water gushing out of the seal when "burping" it, I am not sure I want to attempt that task while the boat is in the water.

The compression is too light if the hose is able to deflect it like that. Check PYI's website for the compression spec for your seal. I believe you will find it to be 3/4" from touching to compressed but don't hold me to that. FWIW, it isn't easy to get it to compress that far. You will need a new set of set screws (there are 2 in each hole). Do not reuse the old ones.

Other things to look at would be engine alignment and/or a loose engine coupling. If it's way off the seal will leak but suspect that isn't the case if you didn't have issues before. You can also polish the seal surfaces with very fine sandpaper if needed to clean them (like 600 grit). Also, if the seal is old, you may want to consider replacing it. The PYI web site will mention what they consider the lifetime of the seal to be. Replacing it will probably open a can of worms, but you'll feel good about the world (well, almost) when done. A lot written in this forum about that.

Yes, the specs say roughly 3/4" compression. But I am sure that would be with a brand new bellows. I am sure the bellows has a set in it since we replaced it maybe 10 years ago. It is not likely that you could compress it 3/4" from touching now that it has a set shorter than original.

My concern is whether or not I could do this task while the boat is in the water. There is a lot of water gushing out of the seal when it is not making solid contact. Adjusting the bellows may take some time and failure to get it re-seated would be a serious problem. Has anyone done this before?

I would not hesitate moving the disk to further compress the bellows with the boat in the water. The advice to not re-use the set screws is correct- buy new ones from PSS, full set of I believe 6. They will provide directions. Also be sure to check the bellows very carefully for any cracking. I think you can compress these ONE time, after that you may need a new PSS kit, bellow.