Dripless shaft packing

[Ted Pounds]

Ron,

I'm with you on this one.  Packing glands have been around since the invention of the propeller.  They're simple and reliable.  And, with the use of new packing materials, dripless.  

Ted

[John Gardner]

Fascinating stuff, since my prop shaft is in the garage and will shortly be re-installed, (I think).    Since I intend using the Gore packing, this is aimed primarily at non-PSS people.  My prop shaft has three slight grooves in it where the packing was previously - smooth, gentle corrugations.  Has anyone got any guidance how much wear is acceptable?  (Perhaps the answer is that it depends how much dripping I'm willing to tolerate!)

Happy New Year everyone,

John Gardner

[dave davis-707-1988- san]

Sounds like this subject could use one more input.
 I had a Teflon type packing installed on Jan. 1995 and about once per year I notice about one or two spoonful of water in the plastic cup I have attched to the area just below the packing gland. In order to frevent this massive intrusion, I hand tighten the packing nut gently without the use of a wrench. I do use a wrench to loosen the lock nut to be able to tighten the packing nut. I will compare my bilge dryness to anyone, except when we have lots of rain.The haul-out yard charged me $59 for the material and they refer to it as Teflon # 105.

[Roc]

When I bought my boat (2000), I had the dealer install a PSS Seal.  After 50 or so engine hours, I used to hear a loud chattering noise.  Apparently, the carbon ring would bounce as the stainless rotor was spinning.  There was no explaination on when this would happen.  Sometimes after motoring perfectly for several hours straight, all of a sudden it would happen (BTW, I have corresponded with others on this site that had the same issue).  

PSS advised to move the ss rotor aft, putting more pressure on the bellows, but that didn't work.  At the Annapolis boat show, I talked to PYI and they agreed to send me a new seal, the water cooled (high speed) version.  For two seasons, I've had no problem with this one.  

About the possible catastrophic event that can happen to this seal certainly is a concern to me.  In hindsight, I may have gone with the Goretex packing, but I didn't know about it when I bought my boat.  When I did discover it, I had already purchased the PSS and was using it.  However, in looking at the traditional packing gland, it is no different than the PSS unit.  A packing gland has a short hose that is clamped to the stern tube on one side, then another clamp on the other side for the bronze packing gland.  This is the same as the bellows (one end clamped to the stern tube, the other on the carbon ring).  In both cases, the hose clamps can fail, or the hose (or bellows) could rupture.  I keep two packs of toilet bowl wax rings nearby in case an emergency seal is needed.  I also visually check the PSS seal frequently, as required with many other boat systems.  I don't think anything on a boat is a 'set it and forget it' type of unit.

Regards,
Roc-

[howard armstrong]

I also have a dripless packing. Not sure of the make as PO had it installed. What size is the ID of the bellows and how long do they normally last?
Mine is begining to look a little used.
Howard
Angelina 648

[Mike Smith]

I have the standard packing gland on Breezer, which I have owned since '97.  From time to time I adjust the nut to increase/decrease the drip frequency.  Every time I mention replacing it with a dripless system to my mechanic (and two other mechanics I know), I am met with ABSOLUTELY NOT! IF IT FAILS, THE RESULT IS CATASTROPHIC AND YOUR BOAT WILL SINK!  I take his advice and go sailing.

Mike Smith
S/V Breezer
www.mikejansmith.com