PSS faulty Bellows

[Rustic Charm]

Originally Posted by phorvati

I am about the put that maintenance kit as well. I have a 1" shaft, 2" tube. My original bellow is 12 years old. I have everything out for inspection. Original bellow looks great. No cracks, gauges or any signs of warping hardening with as much if not more elasticity than the new one from the maintenance kit. Does anyone know what the deal is with this extra rubber insert? I assume its for adapting for different size tubes and i'm not a fan of it. Looks like contact cement or some kind of glue is used to keep the insert. And in terms of set-screws, mcmaster has 8-18 as well as 316. pointed tip ones are listed as high-hold which would seem to improve the issue of rotor slipping. Any thoughts? My rotor takes 5/16"-18 thread.
McMaster-Carr

I'd recommend replacing the bellows. 12 years is pretty good, it's not worth a sudden unknown degraduation.

The rubber insert is for different size stern tubes yes. I don't see a problem with it, it's not rotating and with the clamps on it's going to stay water tight.

No idea about the screws.

[phorvati]

I understand that time is up to replace the bellow. Im just not a fan on what they have done to "improve" the product. I'm not a fan of the company trying to save money by removing Cast/Die for each bellow size and adding inserts. This is one of those parts that should have 0 tolerance for failure. Its not like I'll just keep a spare and replace failed bellow during a voyage or while at anchor. The original did not have this, so clearly they started finding ways to save money in production. I also don't have that vented hose deal. Again, they tried to make the product better, and i just disagree with the change. I'll burp my bellow each time instead of giving water yet another means of sinking me.

[nicholson31]

The PSS seal to me is the most vulnerable point in my boat. After replacing my flex coupling, while in the water, I had to release the collar and push the shaft back 3 inches, Lots of water coming in !!
That got me thinking of how quick the boat will fill up if the bellows ever was compromised, bilge pump would never keep up.
I have made a cover with Velcro sewn for attaching that can be wrapped around the bellows overlapping onto the stern tube and carbon seal. I can then place clamps over the stern tube and carbon seal restricting water flow but will still allow the shaft to turn for motoring if need be, should also still provide some pressure to the carbon seal. Some water will seep through Velcro seams i'm sure but but only minimal compared to nothing there at all and afford me time to get back home.
Interested to know if anyone else has thought of or devised anything for this emergency purpose?

[Rustic Charm]

Originally Posted by nicholson31

The PSS seal to me is the most vulnerable point in my boat. After replacing my flex coupling, while in the water, I had to release the collar and push the shaft back 3 inches, Lots of water coming in !!
That got me thinking of how quick the boat will fill up if the bellows ever was compromised, bilge pump would never keep up.
I have made a cover with Velcro sewn for attaching that can be wrapped around the bellows overlapping onto the stern tube and carbon seal. I can then place clamps over the stern tube and carbon seal restricting water flow but will still allow the shaft to turn for motoring if need be, should also still provide some pressure to the carbon seal. Some water will seep through Velcro seams i'm sure but but only minimal compared to nothing there at all and afford me time to get back home.
Interested to know if anyone else has thought of or devised anything for this emergency purpose?

What size is your shaft?

I completely removed my bellows and played around with the seal and coupling and hardly any water came in. It just seeped in. I wouldn't have liked to have started it up and run it.

[laika]

Originally Posted by nicholson31

The PSS seal to me is the most vulnerable point in my boat. After replacing my flex coupling, while in the water, I had to release the collar and push the shaft back 3 inches, Lots of water coming in !!
That got me thinking of how quick the boat will fill up if the bellows ever was compromised, bilge pump would never keep up.
I have made a cover with Velcro sewn for attaching that can be wrapped around the bellows overlapping onto the stern tube and carbon seal. I can then place clamps over the stern tube and carbon seal restricting water flow but will still allow the shaft to turn for motoring if need be, should also still provide some pressure to the carbon seal. Some water will seep through Velcro seams i'm sure but but only minimal compared to nothing there at all and afford me time to get back home.
Interested to know if anyone else has thought of or devised anything for this emergency purpose?

That's a good idea. When I had mine, I thought perhaps a rag and some self-fusing "rescue tape" (or lots of duct tape) which could be wrapped messily around the intrusion in the heat of battle.

Had also considered somethign similar to what you describe made of heavy fabric with a heavy duty zipper. It would be permanently clamped down to the shaft log behind the PSS and could be pulled over the PSS, zipped closed, and tightened over the shaft with zipties or the like. Probably still wouldn't want to engage the prop, but just something to dramatically cut down the water intake.

Probably already mentioned, but a shaft clamp snugged up against the rotor to keep from sliding back and loosing bellows compression is good cheap insurance.

I didn't have very good luck with my PSSs and reverted back to stuffing box. I had two failures over the years and lost the faith. I know many many others have a lifetime of non-issues with them. The last bellows I bought only lasted for two years before it lost most of it's compressive memory and simply would not keep water out with the prop engaged, no matter how tightly I tried to set the rotor up against it. A new set of yanmar engine mounts may have had something to do with this.

[Rustic Charm]

Originally Posted by phorvati

I understand that time is up to replace the bellow. Im just not a fan on what they have done to "improve" the product. I'm not a fan of the company trying to save money by removing Cast/Die for each bellow size and adding inserts. This is one of those parts that should have 0 tolerance for failure. Its not like I'll just keep a spare and replace failed bellow during a voyage or while at anchor. The original did not have this, so clearly they started finding ways to save money in production. I also don't have that vented hose deal. Again, they tried to make the product better, and i just disagree with the change. I'll burp my bellow each time instead of giving water yet another means of sinking me.

Looking at mine today I don't understand what you are saying the company has replaced? What cast iron collar? The rubber insert couldn't be replaced with a cast iron collar? If it was then how would you seal the cast iron collar?

[transmitterdan]

Originally Posted by phorvati

I understand that time is up to replace the bellow. Im just not a fan on what they have done to "improve" the product. I'm not a fan of the company trying to save money by removing Cast/Die for each bellow size and adding inserts. This is one of those parts that should have 0 tolerance for failure. Its not like I'll just keep a spare and replace failed bellow during a voyage or while at anchor. The original did not have this, so clearly they started finding ways to save money in production. I also don't have that vented hose deal. Again, they tried to make the product better, and i just disagree with the change. I'll burp my bellow each time instead of giving water yet another means of sinking me.

How exactly do you think the rubber insert can fail? From what I can tell this provides a good seal.

The vent hole was added because several people were either too lazy or uninformed to burp. Running the seal dry caused premature failures. No one is making you use then vent. Put a plug in it and burp as before.

[phorvati]

Originally Posted by transmitterdan

How exactly do you think the rubber insert can fail? From what I can tell this provides a good seal.

The vent hole was added because several people were either too lazy or uninformed to burp. Running the seal dry caused premature failures. No one is making you use then vent. Put a plug in it and burp as before.

Idk what can go wrong, but to save on a mold and add rubber insert does not sound like a safe thing to do. For instance, how would you feel if you had an over sized hose for cockpit drain or sink drain and instead of replacing the barbed nipple to fit , you just cut a section of smaller diameter hose to use in between a barbed fitting and drain hose. I wonder what ABYC says about that.

A lot can go bad when you have rotating shaft and other moving parts in tight engine compartment.

[transmitterdan]

Originally Posted by phorvati

Idk what can go wrong, but to save on a mold and add rubber insert does not sound like a safe thing to do. For instance, how would you feel if you had an over sized hose for cockpit drain or sink drain and instead of replacing the barbed nipple to fit , you just cut a section of smaller diameter hose to use in between a barbed fitting and drain hose. I wonder what ABYC says about that.

A lot can go bad when you have rotating shaft and other moving parts in tight engine compartment.

The two scenarios are not alike. There is no water pressure trying to force the bellows off the shaft log. That's why for the PYI seal there are no barbs.

A rubber insert is not a safety issue IMO.

[Rustic Charm]

Originally Posted by transmitterdan

The two scenarios are not alike. There is no water pressure trying to force the bellows off the shaft log. That's why for the PYI seal there are no barbs.

A rubber insert is not a safety issue IMO.

and adding a caste iron insert or what ever would then require yet another rubber insert.

There's nothing wrong with the design.

[Wotname]

Originally Posted by Rustic Charm

and adding a caste iron insert or what ever would then require yet another rubber insert.

There's nothing wrong with the design.

RC, where did you get this idea that PSS is using cast iron inserts?

[Rustic Charm]

Originally Posted by Wotname

RC, where did you get this idea that PSS is using cast iron inserts?

Post 62

[Wotname]

Originally Posted by Rustic Charm

Post 62

Hmm.. There is nothing in post 62 that suggests that PSS is using cast metal as part of the item.

Originally Posted by phorvati

I understand that time is up to replace the bellow. Im just not a fan on what they have done to "improve" the product. I'm not a fan of the company trying to save money by removing Cast/Die for each bellow size and adding inserts. This is one of those parts that should have 0 tolerance for failure. Its not like I'll just keep a spare and replace failed bellow during a voyage or while at anchor. The original did not have this, so clearly they started finding ways to save money in production. I also don't have that vented hose deal. Again, they tried to make the product better, and i just disagree with the change. I'll burp my bellow each time instead of giving water yet another means of sinking me.

The reference to Cast/Die is all about the manufacturing process, not the item itself. It is referring to the potential saving in the manufacturing by having fewer manufacturing Dies because they are making fewer individual sizes for the bellows and then making up the difference with rubber inserts.

[Rustic Charm]

Originally Posted by Wotname

Hmm.. There is nothing in post 62 that suggests that PSS is using cast metal as part of the item.

The reference to Cast/Die is all about the manufacturing process, not the item itself. It is referring to the potential saving in the manufacturing by having fewer manufacturing Dies because they are making fewer individual sizes for the bellows and then making up the difference with rubber inserts.

oh, ok. I didn't grasp that understanding. Now I understand.

[nicholson31]

Rustic Charm:
Interesting you had little water enter around the shaft when removing your Bellows. When I pushed back the bellows and then came forward with the shaft when re installing, the bellows stayed somewhat retracted and water poured in quite fast and in good volume. Once the collar was reset water stopped and had no leaking during last seasons sailing, I'll knock on wood for the up coming year!! My shaft is 1", by the way.
I have my vent plugged as well, agree you have to burp the bellows to get out the air to ensure water pressure on carbon seal.
I also contacted PYI and asked about freezing and ice expansion in the bellows, North East Canada what can I say, and they assured me it poses no issue, nice to know my leaving it full all winter doesn't hurt.
I'm also approaching the 7 year mark with this bellows and was contemplating changing out next year however, in reading some comments on the new PSS seals as being inferior to earlier manufactured seals makes me leary. As Wotname indicated to, are PSI to save money, putting inserts on the ends to accomidate smaller applications?