PSS Shaft Seal - Bellows Degradtion

walmsleyc

walmsleyc

.
Feb 2, 2006
470
Hunter Legend 35 Kingston
I'm a big fan of the PSS Shaft Seal and have had one for 12+ years. I replaced my bellows 3 seasons ago, and the bellows I removed were in perfect condition. I was doing some boat work today and noticed the condition of the rubber. The entire surface was covered with cracks. I mean everywhere. Obviously it needs replacing, but what would have caused this rubber degradation so quickly.

A bit of context, normal summer activities are cruising in freshwater and 25-75 engine hours per season. But last summer we headed out the St. Lawrence doing the Down East Circle Route and did about 426 motoring hours in predominantly salt water. I don't see how additional hours would have caused this because the cracks are even located around the shaft log where there would be no real motion or flex. Seem like an environmental thing, but I can't imagine what.

Any speculations?

Chris


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ggrizzard

ggrizzard

.
May 27, 2004
2,034
Hunter 30_74-83 Ponce Inlet FL
Spilled fuel, bilge cleaning chemicals, PB Blaster (bad for rubber I read), heat....???
I look forward to hearing expert answers.
 
smokey73

smokey73

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Oct 26, 2010
2,023
Hunter 40.5 Beaufort, SC
Really odd to see? I don't think its the salt water or hours of use. Much more likely some sort of spilled liquid, cleaning spray or possibly some sort of vapor present? Have you tried calling the manufacturer?

If your boat is in the water I'd do something about this VERY SOON. Looks like a sinking waiting to happen! By the way, your's looks like its compressed way way more than mine. Is it possible that the compression may have contributed to this? From what I have seen in the video's there was much less compression when installed in accordance with the video.
 
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Justin_NSA

Justin_NSA

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Jul 7, 2004
8,456
Hunter 30T Cheney, KS
Looks like age. Maybe it was an old part they packaged up with a kit. I'd let them know and make it right.
 
walmsleyc

walmsleyc

.
Feb 2, 2006
470
Hunter Legend 35 Kingston
No Ozone generator! Maybe an old part. I do have a query in to the manufacturer, but haven't heard back yet. Not in the water, so not going to sink.

I thought about chemicals, but can't think of anything that would have spilled or been used in that area. I can't image heat could be the issue.

To my mind, it seem like an old product might be a possibility, or something atmospheric because of the uniformity of cracking. A direct chemical spill might not cover the whole bellows so uniformly.

Chris
 
RoyS

RoyS

.
Jun 3, 2012
1,742
Hunter 33 Steamboat Wharf, Hull, MA
Any other rubber hoses near there showing similar deterioration? Hope some bean counter at PSS didn't cheapen the product 3 seasons ago. First thing I will look at when I return to my boat this week. What did PSS say?
 
dmax

dmax

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Jul 29, 2018
1,091
O'Day 35 Buzzards Bay
PSS says if lead acid batteries are in the same compartment as the seal, the change-out should be done sooner than every 6 years (they are very vague) - apparently the off-gassing affects the rubber. Could that be it?
 
Justin_NSA

Justin_NSA

.
Jul 7, 2004
8,456
Hunter 30T Cheney, KS
Well that would suck. Must be the gasses. Should you go with AGM batts if they share a compartment with a PSS?
I think another reason I like the materials that my Lasdrop Gen II is made of.
 
BillyK

BillyK

.
Jan 24, 2010
502
Catalina 310 Ocean City, NJ
Lead acid equalization charging produces Hydrogen and hydrogen sulfide.. I believe the latter is corrosive to rubber.
 
walmsleyc

walmsleyc

.
Feb 2, 2006
470
Hunter Legend 35 Kingston
RoyS said:
Any other rubber hoses near there showing similar deterioration? Hope some bean counter at PSS didn't cheapen the product 3 seasons ago. First thing I will look at when I return to my boat this week. What did PSS say?
Click to expand
My exhaust hose is 6" away, so I will check that and any other rubber nearby (some rubber dust fitting on teleflex cables). The whole engine is close by, but I haven't yet noticed anything going weird on the engine.
 
walmsleyc

walmsleyc

.
Feb 2, 2006
470
Hunter Legend 35 Kingston
dmax said:
PSS says if lead acid batteries are in the same compartment as the seal, the change-out should be done sooner than every 6 years (they are very vague) - apparently the off-gassing affects the rubber. Could that be it?
Click to expand
That is certainly a possibility.

The battery compartment is only "sort of" separated from this area. There is a partial plywood baffle between the two compartments, so they are effectively connected. The shaft log/bellows is at the lowest possible point and could be a place where fumes could settle.

I may properly separate these compartments and add some alternate venting of the battery compartment into the cabin.

Now, I'm not sure why I would go 9 years with no problems, and then suddenly have this problem, but I did change to new batteries recently and added a 3rd battery to the back too, so maybe that change is a factor.

Chris
 
walmsleyc

walmsleyc

.
Feb 2, 2006
470
Hunter Legend 35 Kingston
dmax said:
PSS says if lead acid batteries are in the same compartment as the seal, the change-out should be done sooner than every 6 years (they are very vague) - apparently the off-gassing affects the rubber. Could that be it?
Click to expand
Sure enough, directly from their website:

The bellows will need more frequent inspection and replacement in an environment where non-sealed batteries emit sulfuric acid vapors. Sulfuric acid vapors will accelerate deterioration of any rubber materials including the PSS bellows.
 
Justin_NSA

Justin_NSA

.
Jul 7, 2004
8,456
Hunter 30T Cheney, KS
walmsleyc said:
Now, I'm not sure why I would go 9 years with no problems, and then suddenly have this problem, but I did change to new batteries recently and added a 3rd battery to the back too, so maybe that change is a factor.

Chris
Click to expand
I'm still going with it looks like old age dry rot.
 
G

gfrazzle

.
Aug 26, 2007
266
Hunter 41DS Ventura, California
You did get this directly from PSS and not a cut rate seller right? There are a lot of foreign counterfeit substandard reproductions out there.......
 
walmsleyc

walmsleyc

.
Feb 2, 2006
470
Hunter Legend 35 Kingston
I just received a very nice response from the PYI people. They have offered to replace the whole unit (and have the bellows sent back for analysis).

An except from his e-mail: "I will be curious to see what this is (date) as we are constantly improving the rubber / nitrile formula and I would not expect to see this in any environment with current parts given the UV / Ozone / and other additives we have incorporated in the formula to protect the material (based on testing of current components, the bellows are more or less unaffected by fuels, most common marine chemicals, ozone, uv, etc.) "

So, perhaps it was an old bellows kit (the date will tell). In either case, their customer support is fantastic.

Chris
 
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dmax

dmax

.
Jul 29, 2018
1,091
O'Day 35 Buzzards Bay
Nice - I also had a positive experience with their customer support, very helpful - good company.
 
RoyS

RoyS

.
Jun 3, 2012
1,742
Hunter 33 Steamboat Wharf, Hull, MA
If possible, when you remove the bellows would you visually check the inside for cracks similar to what is on the outside.
 
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