Stuffing box or dripless shaft seals?

[LauraleeG]

I currently have a dripless shaft seal on my Landfall 38 that is not dripless at all. In fact, when the engine revs higher than 1300 rpms...water POURS in. While in a cruise we spoke to a boat mechanic and he opened the bellows up enough for us to stop bailing water, to sail home... but we need to repair or replace this! Repairing/replacing the bellows is an option, but often finding parts that fit an old system is a fools game with out something else going wrong
The cost to replace it with a dripless shaft seal is about 1000$Cad. Or, we could revert back to a stuffing box ...cheaper by far. What are your thoughts? Which way should we go?

[undercutter]

Originally Posted by LauraleeG

I currently have a dripless shaft seal on my Landfall 38 that is not dripless at all. In fact, when the engine revs higher than 1300 rpms...water POURS in. While in a cruise we spoke to a boat mechanic and he opened the bellows up enough for us to stop bailing water, to sail home... but we need to repair or replace this! Repairing/replacing the bellows is an option, but often finding parts that fit an old system is a fools game with out something else going wrong
The cost to replace it with a dripless shaft seal is about 1000$Cad. Or, we could revert back to a stuffing box ...cheaper by far. What are your thoughts? Which way should we go?

Buy your dripless shaft seal ot of Canada or the US. 25% of Australian prices and no GST on imports of less than $1000.00 AU. If the SS face is fine on yours a well a the face of the inside diameter, you only need to buy a new bellows and seals which cost less than $100.00.


Ship fedex for best delivery, 4 business days. Defender is probably a good choice to buy from or a chandler in Canada as I believe they are made there.



Those Ozzies will rip you off big time.


Don't go back to a stuffing box.

[LauraleeG]

Originally Posted by undercutter

Buy your dripless shaft seal ot of Canada or the US. 25% of Australian prices and no GST on imports of less than $1000.00 AU. If the SS face is fine on yours a well a the face of the inside diameter, you only need to buy a new bellows and seals which cost less than $100.00.


Ship fedex for best delivery, 4 business days. Defender is probably a good choice to buy from or a chandler in Canada as I believe they are made there.



Those Ozzies will rip you off big time.


Don't go back to a stuffing box.

Ozzies ripping me off aside.... I am IN canada...so that works!

[undercutter]

Originally Posted by LauraleeG

Ozzies ripping me off aside.... I am IN canada...so that works!

My mistake, I guess i just figured you had to be there as it is the 2nd most expensive country in the world and I didn't think you were in Switzerland.



But seriously, I rebuilt mine 2 years ago fr a 1 3/4 inch shaft for less than $100.00 and your shaft must be smaller. I found it curious that you said the guy opened up the bellows and I assume that you mean compressed it? Sometimes the SS ring will slip resulting in not enough pressure against the faces.

[LauraleeG]

Originally Posted by undercutter

My mistake, I guess i just figured you had to be there as it is the 2nd most expensive country in the world and I didn't think you were in Switzerland.



But seriously, I rebuilt mine 2 years ago fr a 1 3/4 inch shaft for less than $100.00 and your shaft must be smaller. I found it curious that you said the guy opened up the bellows and I assume that you mean compressed it? Sometimes the SS ring will slip resulting in not enough pressure against the faces.

Interesting..the mechanic worked with my partner ( he is the brawn in this operation--I am the...gopher) The mechanic said we might not be able to FIND the parts since the system is old, but in the spring we will take some photos--take it to a place and have them unravel that mystery if we can find the right parts.
But the big decision posed by the mechanic was you can switch back to stuffing box, or repair/replace the current system but good luck finding parts to repair it!!
So sounds like repairing might be more possible than the mechanic led us to believe! Where did you get your parts?

[mvweebles]

There aew a few different brands out there. By far, most common in US is PSS. Replacement bellows and hose clamps are $92 from the manufacturer PYI. Your mechanic must have been including a haul out, which would be needed regardless of replacement stuffing box. They recommend replacing the bellows every 6-years.

There is nothing wrong with conventional stuffing boxes - there are modern stuffing materials that reduce dripping to zero. When a PSS fails, it does so catastrophically, but failure is almost always related to the the set screw on collar being improperly installed and backing out, permitting ghr collar go back away due to pressure from spring- bellows (there are two set screws - second one presses into first one). When a traditional stuffing box fails, it's because the stuffing has aged and become brittle. This often leads to the operator over-tightening the pressure ring, and can easily score the shaft. Pick your poison.

https://store.pyiinc.com/collections...roduct_reviews

[Suijin]

A whole new PYI PSS shaft seal is $300 US. If the current seal is old and of indeterminate origin I'd just replace the whole thing.

Leaks tend to come from two things 1) contamination between the stator and rotor surfaces. "Burping" the seal by pulling the bellows back to allow water to flush the surfaces usually clears that. 2) Inadequate pressure of the rotor against the stator. Reposition the rotor to further compress the bellows.

It's a good idea to put a SS collar, or even just a shaft zinc, behind the rotor as backup to keep it from slipping should the allen screws fail.

[NYSail]

I have always had a traditional stuffing box and loved the simplicity of them...... until my new boat. It came with a Volvo dripless deal and I love it. No bellows.... and so far not a drip...... burp at beginning of season with a little squeeze, push in a small amount of grease and I’m done. Bone dry....

Good luck!

[sailormed]

Originally Posted by NYSail

I have always had a traditional stuffing box and loved the simplicity of them...... until my new boat. It came with a Volvo dripless deal and I love it. No bellows.... and so far not a drip...... burp at beginning of season with a little squeeze, push in a small amount of grease and I’m done. Bone dry....

Good luck!

+1

I replaced my stuffing box with a Volvo and are now gathering dust in my bilge. Just be aware that manufacturer indicates a replacement every 5 years. In reality it lasts much longer, but that way the mf has no responsibility.


My neighbour replaced the still perfectly functioning Volvo on his boat after 18 years!!! Just saying.

[NYSail]

And the price for the volvo is very reasonable..... mine is 10 years old and still is perfect but to replace would be $120.... not bad.

[a64pilot]

Originally Posted by mvweebles

There is nothing wrong with conventional stuffing boxes - there are modern stuffing materials that reduce dripping to zero. When a PSS fails, it does so catastrophically, but failure is almost always related to the the set screw on collar being improperly installed and backing out, permitting ghr collar go back away due to pressure from spring- bellows (there are two set screws - second one presses into first one). When a traditional stuffing box fails, it's because the stuffing has aged and become brittle. This often leads to the operator over-tightening the pressure ring, and can easily score the shaft. Pick your poison.

Thai pretty much sums it up. But I’d also say that just about anything needed done to a stuffing box can easily be done in the water, where a dripless often requires the boat to be pulled, and depending on where you are the ability to haul a boat may be days or weeks away.
I was all set to go dripless, and on a whim put Teflon packing in, three years ago. Since then it’s been dripless, will form a wet ring on the shaft when underway, but won’t drip, runs cool and hasn’t been adjusted yet.
I may yet one day go dripless just to try it, but with Teflon packing in my stuffing box I’m dripless now without any of the drawbacks that I can see.

[NorthernMac]

From the research I’ve done for my repower coming up.

Stuffing box drips a few times a minute, if it’s not happy a few time a second, can be temporarily repaired by stuffing whatever into the stuffing box, not prone to catastrophic failure.

Dripless doesn’t drip, but when it does, it can get a little...sporty.

For me I’ll be sticking with a stuffing box with modern stuffing, a few drips a min isn’t really a big deal for me, only keeps the very aft section of bildge wet, and I am not tolerant of the failure mode of the dripless, especially in a boat that could be a good ways from land, your mileage may vary.

[JOHNMARDALL]

On the PSS seal from PYI, the alignment of the faces of the graphite block and stainless steel collar are critical and not easily corrected by compressing the bellows. I installed a new dripless seal assembly and could not stop it dripping fast until I realized that it was being pushed out of alignment by the lubricating water hose. I installed two elbows in that hose to that the connection was hanging "loose" under the assembly and the dripping stopped. The installation instructions said nothing about this. For me that's too sensitive and I'll be replacing the seal assembly with another type next time I haul the boat.


All the best
John Mardall

[Scaramanga F25]

6 boats over 43 years all with stuffing box, Canada, USA, Bahamas never a problem. Maintenance at haulouts. Occasional drip check.
Dripless are better suited for fast high shaft RPM Power boats.

[Ken Z]

Go with the stuffing box, I have seen too many failures with the dripless.