[C320-list] Dry bilge?

[Allan S Field]

Doug - On Sea Shadow, we still have the original shaft and for 2 PSS installs, the shaft did not have to be removed.  Could it be that your mechanic has an economic incentive for telling you that the shaft has to be pulled, the rudder dropped and that you need to buy a bronze shaft and maybe through him? (grin!)  

As for fragility of the bellows, I talked with PYY at a boat show as I was particularly concerned about the water in the bellows freezing over the winter and possibly rupturing the bellows.  I was advised by PYY that this is not an issue and given that I leave the boat in the water year round and it has survived every winter, including the brutal one last year, I don't think this is an issue.  Tehse things are quite robust and had a boat ever sunk for this reason, I think we would have heard of it.  When our about 12 year old bellows was replaced this year when the boat was hauled for bottom painting, the bellows still looked fine with no signs of cracking or wear and tear.  Again, we replaced it out of an abundance of caution and to get the non-burping function.

Allan S. Field
Sea Shadow - #808
Columbia, MD

-----Original Message-----
From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Doug Treff
Sent: Thursday, November 20, 2014 8:50 AM
To: C320-List at catalina320.com
Subject: Re: [C320-list] Dry bilge?

Scott,

If your stuffing box is dripping that much when the engine is not in gear, it probably needs tightening. It should not drip at all (or VERY
little) unless your engine is in gear. The drip rate you mention is what would be normal when the shaft is turning. If you are unable to stop the drips when sitting still, it may be time to repack the stuffing box.

See an excellent article on this topic by Don Casey: 
http://www.boatus.com/boattech/casey/stuffing-box.asp

There are different types of stuffing media available which advertise to be drip free. I have not used any of them so I will not endorse any product. Maybe some other members who have used these products will speak up.

Of course the most expensive option (and definitely drip free) is to switch to the PSS shaft seal, but this is a pretty big job. When I was contemplating the PSS, my mechanic told me that I would also need to replace my bronze prop shaft with Stainless Steel in order to do the job. I declined and went with traditional packing. On the C320, you will have to drop the rudder to get the shaft out. All these things start to add up quick, making this a potentially expensive job. Some people also don't like the PSS product because the rubber bellows is much more fragile than the shaft hose and if it splits or gets torn, your boat will sink. I have honestly never heard of this happening, but people do mention it. I have also heard that the bellows must be replaced every six years (per PSS website) which will naturally require the prop shaft to be pulled back, removal of the coupling, and a possible realignment.

My point is this: Each one of these packing systems is a compromise. On conventional systems you can repack every few years without having to pull the shaft. The compromise is a wet bilge. On the PSS system, you will have a dry bilge but will face the added expense of pulling the shaft to replace the bellows periodically. Your call.

My advice: get an estimate, taking into account all the things I mentioned above (replace shaft if yours is bronze, drop rudder, cutlass bearing replacement (might as well if the shaft is out) cost of PSS itself, etc. Show this estimate to your wife and let her decide if a dry bilge is worth that expense. She may just change her tune.

---
Doug Treff
September Song Hull #350
doug at treff.us

On 2014-11-20 07:09, Scott Westwood wrote:
> I have seen several notes on how to re-pack stuffing boxes etc...
> 
> I also have heard different takes on dripping and "drip less" vs.
> "dripless".  My wife "hates" water in the bilge with a passion.
> 
> Is there a truly safe way to get a dry bilge?  Cost/benefit analysis?
> You can but it would cost as muchas the boat etc???
> 
> Our box drips 3-5 drips/minute even at the dock.  Is this normal?  I
> hear it is for cooling underway etc...
> 
> 
> What thoughts are out there?
> 
> One concern we both have is the odd chance that we have a bilge pump
> failure (or battery failure) at the dock.  We have shore power but we
> often can't get to the boat for a month or so.  Worst fear is bilge
> pump failure and boat sinks.  I know it should not happen within a
> month or so but there is also the fear of wood deck damage if bilge
> water rises etc...
> 
> 
> Thoughts out there?
> 
> 
> Scott Westwood scottwestwood at bellsouth.netH (919)-362-8538C 
> (919)-618-7185