Dripless: Is it all that?

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Patches

Considering a dripless shaft seal to replace the stuffing box.  In my case would also mean changing the prop shaft (I have original bronze), and while I'm at it maybe a flexible coupler.  My shaft is 30 years old, and the stuffing box looks pretty old too.  Either way, I'm going to have to haul the boat just to replace the hose, clamps, etc for the new stuffing box.

Looking for feedback from those who have made the switch.  I have heard different sides, but not from other C34 owners.  I've heard everything from life changing praise, to not quite as "dripless" as advertised, to safety arguments for retaining the traditional stuffing box.

Thanks,

Patches

Jim Hardesty

Patches,
If you haven't already, do a search from the main message board for "dripless", a lot of discussion and problems.
Jim
Jim Hardesty
2001 MKII hull #1570 M35BC  "Shamrock"
sailing Lake Erie
from Commodore Perry Yacht Club
Erie, PA

Robert Mann

Patches
Mine has had a dripless from new, in 2002.  It was installed by the dealer for the PO, I know the history.  Mine is now dripless, literally.  I have just replaced the original 4 or 5 weeks ago, although according to the manufacturer the bellows should be replaced every 7 years, I think.  The old one I removed was beginning to allow water to pass, when the boat was in astern to slow down, under a good engine speed.  I suspect the spring had weakened as my boat sat during an overseas posting, and it was 18 years old. The bellows that came out appears in good shape, from a rubber perspective. The stern tube is long on the C34 and the bellows should be measured according to the installation instructions, so the stern tube does not protrude too far into the bellows.  I would measure the stack of PSD and coupling very carefully as the issue of the stern tube moves the bellows towards the engine. and there is not much room to work with couplings.  Remember the PSS is decompressed while you refit the shaft to the coupling so there isn't much room between the stainless collar and the coupling, and care is need not to damage the carbon face.  Make sure the shaft is centered in the stern tube and that the couplings halves are aligned per the manual.  You will see in the picture the 2 carbon lines on the inside of the hull.  The rear one shows how for 18 years the bellows was too far aft, but you will get the space perspective.  I hate wet bilges and I must say, for me the PSS system has worked well.
Catalina 34 MkII, Indigostar, 2002 no 1622, Tall Rig, M35-BC

Ron Hill

#3
Patches : If you look on the Main Board you'll find all kinds of discussion!!  Nothing like a clean DRY bilge!!

I went for the Dripless Packing (Gore) with a Flex coupling and have had them for over 25 years!!   :thumb:

A few thoughts
Ron, Apache #788

Noah

On the flipside. I have standard stuffing box, stainless shaft and Vetus Bullflex coupling, with Gore packing, (all five years old) and it is virtually drip-free.
1990 hull #1014, San Diego, CA,  Fin Keel,
Standard Rig

dfloeter

I went with the PSS and even though it is now dripless, the original stuffing box with Gore packing would have so much simpler and cheaper. 
Dietrich Floeter
Traverse City MI
1996 Catalina 34 TR WK #1317
Universal M35A
Rocna 20

Robert Mann

Dietrich, you are probably correct.  If you look at the photo there is a very feint pencil line on the shaft, showing the 3/4" decompressed mark.  Hence, my comments regarding the space claim of the PSS and the need to measure carefully if flex couplings or any non standard couplings are intended.  I have a brand new Buck Algonquin split coupling as a desk paper weight due to this last point!  That would not have been an issue with a standard stuffing box and Gore Packing, as Ron and Noah have.
Catalina 34 MkII, Indigostar, 2002 no 1622, Tall Rig, M35-BC

Jim Hardesty

QuoteConsidering a dripless shaft seal to replace the stuffing box.  In my case would also mean changing the prop shaft (I have original bronze), and while I'm at it maybe a flexible coupler.  My shaft is 30 years old, and the stuffing box looks pretty old too.  Either way, I'm going to have to haul the boat just to replace the hose, clamps, etc for the new stuffing box.

If you do all that, probably want to add a new cutlass bearing to your list.  FWIW the second season I had Shamrock I changed the cutlass bearing (was well worn at 400 engine hours), changed stuffing box packing to gortex packing and did a careful engine alinement.  Now have 1500 engine hours and the cutlass bearing is still tight and the stuffing box packing may need little adjustment in the spring, is good throughout the rest of the season.  Drips very little.  I keep a small kitchen type sponge under the stuffing box and the water evaporates there.  I'm in fresh water so no problem there.
Jim
Jim Hardesty
2001 MKII hull #1570 M35BC  "Shamrock"
sailing Lake Erie
from Commodore Perry Yacht Club
Erie, PA

Ron Hill

Guys : You really want to look at a "dripless" packing gland if you are in salt water.
Salt water in the bilge is smelly, corrosive and downright nasty!! - when compared to fresh water!!   :cry4`

A thought 
Ron, Apache #788

Ted Pounds

Quote from: Ron Hill on October 20, 2020, 01:55:14 PM
Patches : If you look on the Main Board you'll find all kinds of discussion!!  Nothing like a clean DRY bilge!!

I went for the Dripless Packing (Gore) with a Flex coupling and have had them for over 25 years!!   :thumb:

A few thoughts

What Ron said.  👍👍
Ted Pounds
"Molly Rose"
1987 #447

Patches

As always, great feedback.  Thank you!

I'm in saltwater year round.  Packing was replaced about 2 1/2 years ago when I purchased the boat.  I'm going to guess I have about 450 hours of engine time on the new packing (she operates as a charter boat).  Stuffing box now starting to drip more, so at a minimum, I want to change the packing.

Although the dripless shaft seals look intriguing, it seems the rotor (which compresses the bellows and --as I understand it --is held in place with set screws) would want to "loosen" over time and walk towards the coupler and relax the bellows leading to leaking.  I noted that Mainesail, in his typically articulate way, described adding a stainless collar clamp just forward of the rotor to prevent this.  Then there is the issue of venting the thing, and allowing air/water to escape when/if air gets into the bellows.

I guess I'm leaning more toward Ron and Noah's solution which is to replace the original stuffing box,  buy a new stainless shaft and coupler, and use a quality packing material.  Which raises these new questions:

(1) Do people agree that I should try to work with a local prop to (a) make the new shaft and (b) fit/face it to the new coupler?  Tacoma Propeller is relatively close by, and seems to have a good reputation.

(2) The prop shop would need to know the prop length and the new coupler I want to use. What I've read on the forum is kind of unclear on prop length (57" for my hull no. 1016, to 58"-59").  And of course to know for sure I've got to cut the old one out for an accurate measurement--which means I'm on the hard. Is there any definitive word on this?

(3) At a minimum I'm going with a new split coupler.  Are the benefits of a new "flexible" coupler--Bullflex or Federal--worth the extra cost?  I have no problem spending the money if the benefit is there.

Thank again for your feedback.

Patches



Robert Mann

Patches, the PSS is locked in the shaft with set screws.  The set screws then have a second screw above them, locking them in place.  All four set screws have blue loktite  on them as a secondary precaution. 

If I had the choice, I would use a local prop shop to machine the shaft to fit the coupling you choose, cut the shaft to length, cut the taper for the prop and thread the end for the prop nuts and cotter pin.  If I were doing this i would also have them lap the prop to the taper.  By doing it this way you know all the parts fit and the quality is good.  Doing it remotely would bee my second choice.
Catalina 34 MkII, Indigostar, 2002 no 1622, Tall Rig, M35-BC

captran

I had a traditional stuffing box on a Newport 30 and it seems I could never get a consistent tightness , but that was before some of the new packing material was out.  When I bought my C 34 in 2001 part of the deal was to include a PSS and a Y valve.  My only complaint is that in some conditions of heel and following waves it seems like a little air gets in the bellows which dries out and consequently caused a squealing sound where the zinc mates.  Now every week or so depending on what conditions have been I burp the bellows which prevents the squeal from occurring.  and it seems like there is always a little zinc residue similar to what you see in the pic, as well as minute specks of water.  the mechanic says that's normal.  even though it didn't look worn after 12 years I had mine replaced.  I put on abut 100 engine hours per year in 2 1/2 months of daily cruising.
Randy Thies
Voyager  1997 #1345
was Florida, now Anacortes Wa

Roc

Randy
Go on the PYI site and they suggest running a hose from the SS rotor to a point above the waterline.  That will keep water in the bellows.  There should be a barb coming out of the ss rotor for a hose connection.  I'm thinking you may have an older part.
Roc - "Sea Life" 2000 MKII #1477.  Annapolis, MD