I'm wanting to switch between a pss and go back to the stuffing box???
- Thread starter Bear
- Start date
Close but not the right size
I have a "spare" bronze factory stuffing box, sitting in my basement Boat Locker... ever since I installed a PSS shaft seal on our boat in '95. Unfortunately for your boat, our boat has a 1" shaft.
Perhaps someone else has a spare one in the smaller size, but I seem to recall that most boats in our size range (with diesels anyway) have the 1" shaft size.
Good luck,
Loren
ps: I would be very reluctant to go back to using the old stuffing box and packing. A dry bilge is nice to have.
I have a "spare" bronze factory stuffing box, sitting in my basement Boat Locker... ever since I installed a PSS shaft seal on our boat in '95. Unfortunately for your boat, our boat has a 1" shaft.
Perhaps someone else has a spare one in the smaller size, but I seem to recall that most boats in our size range (with diesels anyway) have the 1" shaft size.
Good luck,
Loren
ps: I would be very reluctant to go back to using the old stuffing box and packing. A dry bilge is nice to have.
Alan Gomes
Sustaining Partner
A 3/4" shaft seems to be an awfully small diameter for that boat. I would have expected it to be at least 1". Are you 100% sure about that diameter?
As for your question: Check out this place as having all the parts you would need: https://www.deepblueyachtsupply.com/ Note that you should use stuffing box hose, which has a much thicker wall thickness than plain old exhaust hose.
I've seen a PSS fail. It's way more scary. Also I may need to double check my shaft size.
tenders
Innocent Bystander
You're probably correct. My '69 E32 with an Atomic Four and V-drive has a 3/4" shaft. Many E35s with A4s also have 3/4" shafts. Plenty strong.
I don't think you're crazy at all to go back to a stuffing box. With Teflon flax packing it's a whole new ballgame from the old stuff...which, since I've had a chance to compare it to a shaft seal for many years, worked pretty well too.
A shaft seal is a somewhat more complicated solution to the problem of preventing a spinning shaft from dripping. I don't think it's better, because its failure mode tends to be catastrophic.
I don't think you're crazy at all to go back to a stuffing box. With Teflon flax packing it's a whole new ballgame from the old stuff...which, since I've had a chance to compare it to a shaft seal for many years, worked pretty well too.
A shaft seal is a somewhat more complicated solution to the problem of preventing a spinning shaft from dripping. I don't think it's better, because its failure mode tends to be catastrophic.
Bear,
Buck Algonquin is one reputable manufacturer of the parts you need, the link below provides an example.
http://www.rnrmarinestore.com/default.php?cPath=2792298_6667295
I have considered the same switch because I have my prop shaft out at the moment. My shaft had some wear from the original stuffing box before the PO switched to the PSS so I would most likely need a new shaft and then the cost of the new stuffing box on top of that. I chose to buy a new bellows for the PSS instead.
What was the failure mode of the PSS you saw.:0
I did have an incident where I was getting some leakage when I splashed last spring, the mating surfaces on the PSS had gotten some deris between them during a project a month earlier and it was enough to cause a dribble when it went in the watter, but a quick spin of the prop flushed out the fouling. Also my PSS was installed incorrectly with not enough tension on the bellows by the original installer which didn't help the issue. I also purchased a split collar per Mainsails advice to make double sure that nothing moves around down there. I was surprised by how good my old bellows looked after 15 years. It looks and feels as good as the new one actually, but the new one was still worth the peace of mind.
I am the first one to agree however that both systems have their strong and weak points, in the end you chose the strengths that you need and the weaknesses that you can live with.
Buck Algonquin is one reputable manufacturer of the parts you need, the link below provides an example.
http://www.rnrmarinestore.com/default.php?cPath=2792298_6667295
I have considered the same switch because I have my prop shaft out at the moment. My shaft had some wear from the original stuffing box before the PO switched to the PSS so I would most likely need a new shaft and then the cost of the new stuffing box on top of that. I chose to buy a new bellows for the PSS instead.
What was the failure mode of the PSS you saw.:0
I did have an incident where I was getting some leakage when I splashed last spring, the mating surfaces on the PSS had gotten some deris between them during a project a month earlier and it was enough to cause a dribble when it went in the watter, but a quick spin of the prop flushed out the fouling. Also my PSS was installed incorrectly with not enough tension on the bellows by the original installer which didn't help the issue. I also purchased a split collar per Mainsails advice to make double sure that nothing moves around down there. I was surprised by how good my old bellows looked after 15 years. It looks and feels as good as the new one actually, but the new one was still worth the peace of mind.
I am the first one to agree however that both systems have their strong and weak points, in the end you chose the strengths that you need and the weaknesses that you can live with.
Last edited:
tenders
Innocent Bystander
My failure was caused by a pinhole leak in the gas tank causing the bellows to be immersed in gasoline. This dissolved the rubber part of the bellows and left schmutzy, flimsy canvas backing in place. It happened on the hard but the boat would have sunk at the mooring.
Also, the rings or faces of the seal eventually wear and have to be replaced. This requires removing the coupling from the shaft, which is a huge pain.
My installation has never been bone-dry either. And I worry that some grit, dropped tool, or misguided boat hook from the bilge or lazarette will get between the faces of the seal, or misalign the bellows, and cause a leak.
And now - you mention engine heat. Great, I hadn't worried about that before. Add that to the list. Thanks.
With the stuffing box, nothing is fragile and all the bits are pretty much wrapped in that indestructible thick hose anyway. The hose and bronze can last for decades, the hose clamps can be replaced without removing anything else, and the flax packing can be replaced with a minimum of disassembly, time, or cost. And Teflon packing might last as long as the rest of the system.
Also, the rings or faces of the seal eventually wear and have to be replaced. This requires removing the coupling from the shaft, which is a huge pain.
My installation has never been bone-dry either. And I worry that some grit, dropped tool, or misguided boat hook from the bilge or lazarette will get between the faces of the seal, or misalign the bellows, and cause a leak.
And now - you mention engine heat. Great, I hadn't worried about that before. Add that to the list. Thanks.
With the stuffing box, nothing is fragile and all the bits are pretty much wrapped in that indestructible thick hose anyway. The hose and bronze can last for decades, the hose clamps can be replaced without removing anything else, and the flax packing can be replaced with a minimum of disassembly, time, or cost. And Teflon packing might last as long as the rest of the system.
The issue with dripless shaft seals is that failure of the rubber accordion admits water forcefully into the boat--a geyser. Not true of a trad stuffing box.
However, the "danger" is far overrated. There is almost no danger of the metal faces going wrong. They can be cleaned with a rag, or burped if they leak. Which they don't. They last effectively forever.
The rubber accordion should be replaced on a schedule. As I recall, the manu recommends 6 years ( correction: 11 years). Since this means pulling the shaft off, few do it.
Dripless shaft seals work and are well proven, and there is no reason at all for emergency replacement with a traditional box. At time of rubber replacement, it makes sense if desired.
A broken accordion can be sealed at sea with latex rubber sheet held in place with hose clamps.
The engine can still be used in neutral, for charging. But with a temporary seal, the shaft can;t turn--so, no motoring.
However, the "danger" is far overrated. There is almost no danger of the metal faces going wrong. They can be cleaned with a rag, or burped if they leak. Which they don't. They last effectively forever.
The rubber accordion should be replaced on a schedule. As I recall, the manu recommends 6 years ( correction: 11 years). Since this means pulling the shaft off, few do it.
Dripless shaft seals work and are well proven, and there is no reason at all for emergency replacement with a traditional box. At time of rubber replacement, it makes sense if desired.
A broken accordion can be sealed at sea with latex rubber sheet held in place with hose clamps.
The engine can still be used in neutral, for charging. But with a temporary seal, the shaft can;t turn--so, no motoring.
Last edited:
Frank Langer
1984 Ericson 30+, Nanaimo, BC
Why could one not tape a leak in the rubber accordion piece with self-amalgamating Rescue Tape and then still operate the engine to return to port? That tape holds pretty well, is not expensive, and should adhere over the rubber fairly well, I would think. Are there any other emergency fixes if the rubber bellows begins to leak while underway?
I spoke with a factory rep from PSS about the need for replacement. Their website suggests replacement every 11 years. However, the rep told me that they have to be wary of liability issues, and he has seen them go 25 years without problems. He advised checking for any stiffness in the rubber, beginning cracking or other signs of age, and if found, to replace it. He said they usually don't fail in a catastrophic manner. I think it may depend a bit on whether the PSS is immersed in an oily bilge or is sprayed with petroleum product during engine maintenance or other risky stuff. In many boats, it sits above the hull floor, away from any contaminants.
I recently checked the PSS on our boat, and it still looks like new and functions perfectly. I decided that it was likely fine and didn't replace it.
Frank
I spoke with a factory rep from PSS about the need for replacement. Their website suggests replacement every 11 years. However, the rep told me that they have to be wary of liability issues, and he has seen them go 25 years without problems. He advised checking for any stiffness in the rubber, beginning cracking or other signs of age, and if found, to replace it. He said they usually don't fail in a catastrophic manner. I think it may depend a bit on whether the PSS is immersed in an oily bilge or is sprayed with petroleum product during engine maintenance or other risky stuff. In many boats, it sits above the hull floor, away from any contaminants.
I recently checked the PSS on our boat, and it still looks like new and functions perfectly. I decided that it was likely fine and didn't replace it.
Frank
Last edited:
That might well work. Certainly worth a try, if it will anneal while wet.
Before the Hawaii sail, I tested the latex emergency repair idea by jamming a piece of wood between the metal disks. This causes an attention-getting flood.
I was able to stop it with multiple (wet!) turns of several feet of stretchy latex, and hose clamps. In the real world I would have wrapped that with duct tape, too.
Before the Hawaii sail, I tested the latex emergency repair idea by jamming a piece of wood between the metal disks. This causes an attention-getting flood.
I was able to stop it with multiple (wet!) turns of several feet of stretchy latex, and hose clamps. In the real world I would have wrapped that with duct tape, too.
Bellows PSS
I changed mine out last year when I did the Cutlass Bearing, Since I was doing the work the PSS was installed by the PO sometime in the late 90s. Well the old bellow looked as good as new so I bagged it and put it in my spare parts kit. So even after 15 plus years it was not a issue. Just check it when you check the Transmission oil for cracking and don't worry about it the bellows is very well built.
At least that is mine opinion.
I changed mine out last year when I did the Cutlass Bearing, Since I was doing the work the PSS was installed by the PO sometime in the late 90s. Well the old bellow looked as good as new so I bagged it and put it in my spare parts kit. So even after 15 plus years it was not a issue. Just check it when you check the Transmission oil for cracking and don't worry about it the bellows is very well built.
At least that is mine opinion.
Update:
I just put my new pss bellows in place and it is a bit thicker on the outboard end where it slides over the shaft tube that is glassed into the hull. The original pss bellows was a TIGHT fit and the new one is just enough larger that I have had to expand the clearance between the hull and the tube by hand, I have been laying in the quarter birth and using a hole saw in my right hand to scrape out enough clearance to allow for the new bellows to fit. there was kind of a messy glob of fiberglass right under the tube that is causing me the clearance issues. I'm not removing enough to be a structural issue but doing this job wit out messing up the fragile tube has been tedious. Its not a nice job, and I have spent about an hour and a half back there so far and I think another half hour will finish the job.
So.... if you are getting into this swap have a close look at the clearance under the tube as it may affect your decisions.
The pss bellows on my small model has a step down rubber insert inside of the outboard end (double thick) that those of you with larger boats with larger tubes won't have, so its probably unique to my situation but I still wanted to pass my experience on to everybody else.
I just put my new pss bellows in place and it is a bit thicker on the outboard end where it slides over the shaft tube that is glassed into the hull. The original pss bellows was a TIGHT fit and the new one is just enough larger that I have had to expand the clearance between the hull and the tube by hand, I have been laying in the quarter birth and using a hole saw in my right hand to scrape out enough clearance to allow for the new bellows to fit. there was kind of a messy glob of fiberglass right under the tube that is causing me the clearance issues. I'm not removing enough to be a structural issue but doing this job wit out messing up the fragile tube has been tedious. Its not a nice job, and I have spent about an hour and a half back there so far and I think another half hour will finish the job.
So.... if you are getting into this swap have a close look at the clearance under the tube as it may affect your decisions.
The pss bellows on my small model has a step down rubber insert inside of the outboard end (double thick) that those of you with larger boats with larger tubes won't have, so its probably unique to my situation but I still wanted to pass my experience on to everybody else.