PYI or PSS

[Celestialsailor]

Before I take off this year, I thought I would either replace or at least have a spare bellows for my dripless stuffing box. I looked online and the only 2 I can see are PSS and PYI. They look almost identicle in the pictures. Is there any way of telling one from another? I'm not sure which one I have...

[s/v Jedi]

I believe it is the PSS shaft seal, made by PYI ?

[LeaseOnLife]

Originally Posted by s/v Jedi

I believe it is the PSS shaft seal, made by PYI ?

I think so too.

Also look at Lasdrop shaft seals

[Celestialsailor]

Here is the unit...

[DeepFrz]

That is the PSS shaft seal made by PYI.

[Celestialsailor]

Ok thanx. Also, the ones I see in te pictures have some kind of nipple on them. Mine doesn't. So it came into question.

[sailorboy1]

Originally Posted by Celestialsailor

Ok thanx. Also, the ones I see in te pictures have some kind of nipple on them. Mine doesn't. So it came into question.

Because your seal is old and before they all had the vent tube for us with slow sailboats (mine is the same way).

be sure to get the rebuild kit withthe new sets screw and not just a bellows if you are going to get 1.

[LeaseOnLife]

the nipple (withe a hose attached, end some distance above the waterline) allows trapped air to escape. Or you can divert some raw water from engine cooling into it. Purpose: lubrications / cooling of the sealing surface, it doesn't like to run dry.

Edit: don beat me to it

[Irish rambler]

I have a PSS seal fitted with the vent tube on my motor cruiser and it's been very good, just fit and forget (apart from routine inspections) I've no connection to the company other than a very satisfied customer.

[senormechanico]

PYI sells PSS shaft seals (by the seashore).

Earlier models (like yours and the one I had on my previous boat) didn't have the vent nipple.

PSS models made for high speed boats had the nipple for forced water injection for cooling and to prevent air from being sucked past the seal when the boat was planing.

In my previous boat, I replaced the original bellows after about ten years when it gradually lost its push against the seal.
It became apparent when we motored more than normal cruising speed, as the extra thrust on the soft Yanmar motor mounts allowed the seal to pee in the bilge.
It was nothing the bilge pump couldn't handle, but I got tired of listening to the bilge chime going off every few minutes (car ignition ding dong thingie).

Apparently, PYI just decided to make one model.

For sailboats, install a vent tube and leave the end open well above your waterline and it will automatically fill the shaft log upon launch.
Powerboats need to hook the tube to the water pump">raw water pump output for bearing cooling.

[Celestialsailor]

Originally Posted by LeaseOnLife

the nipple (withe a hose attached, end some distance above the waterline) allows trapped air to escape. Or you can divert some raw water from engine cooling into it. Purpose: lubrications / cooling of the sealing surface, it doesn't like to run dry.

Edit: don beat me to it

I can't see a reason it would ever run dry. I burp mine when I put it back in the water...end of issue. The serations in the cutlass bearing guarentee a water supply.

[Celestialsailor]

Originally Posted by senormechanico

PYI sells PSS shaft seals (by the seashore).

Earlier models (like yours and the one I had on my previous boat) didn't have the vent nipple.

PSS models made for high speed boats had the nipple for forced water injection for cooling and to prevent air from being sucked past the seal when the boat was planing.

In my previous boat, I replaced the original bellows after about ten years when it gradually lost its push against the seal.
It became apparent when we motored more than normal cruising speed, as the extra thrust on the soft Yanmar motor mounts allowed the seal to pee in the bilge.
It was nothing the bilge pump couldn't handle, but I got tired of listening to the bilge chime going off every few minutes (car ignition ding dong thingie).

Apparently, PYI just decided to make one model.

For sailboats, install a vent tube and leave the end open well above your waterline and it will automatically fill the shaft log upon launch.
Powerboats need to hook the tube to the raw water pump output for bearing cooling.

So I take it you were happy with the unit? This s my first experience with one. The design seems sound. Does the carbon seal last forever or is that another maintenance experience?

[s/v Jedi]

Originally Posted by Celestialsailor

I can't see a reason it would ever run dry. I burp mine when I put it back in the water...end of issue. The serations in the cutlass bearing guarentee a water supply.

Correct. With the vent there is no burping needed anymore

[Randyonr3]

The.new unit with the nipple and vent tube is used instead of having to burp the bellows. If it gets air in there, (normally from backing up ) as the prop will blow air up the log, it will sound as a .rumble comming from under the boat,
If you decide to buy a new bellows, let me know, and you can pick it up across the street on my account.

[Randyonr3]

Just a note, I'm going the other way with mine on the next haul out, reason is the bellows , from the manufacture are to be replaced every few years, ant the boat needs to be hauled to do so, the old style packing gland can be rebuilt in an anchorage and with the new gore and grafite packing, no need to accept a drip.