Ben,
 Do you recall what flow sensor/meter you used. I added a flow sensor on the main water intake, and think you have a great Idea to add one on the pressurized shaft seal hose. BTW, I launch and retrieve our NT 32-287 4 times on most years ( If we get to go cruising, we have a trailer) and have never had to burp the shaft seal.  The water supply for the shaft seal on our Volvo 280 is supplied immediately after the raw water pump. NT 32-2887, 2007William L. Bowen4393 Burnham Woods Dr.Franklin, OH 45005Voice & Fax: 513-425-9388Email: SVToybox@aol.comIn a message dated 2/1/2025 5:20:19 PM Eastern Standard Time, sentoa-request@lists.sentoa.org writes: 
Date: Sat, 1 Feb 2025 14:19:57 -0800From: Ben McCafferty bmacpiper@me.comSubject: [Sentoa] Re: Cutlass Bearings & shaft sealsTo: "South East Nordic Tugs Owners' Association (SENTOA)"    sentoa@lists.sentoa.orgCc: Joe Pucciarelli jpucciarelli@sdmmetro.comMessage-ID: 99127790-01B4-4CA2-B817-A8C41AFC1D0E@me.comContent-Type: text/plain;      charset=utf-8 Adding my $.02 also. There is a new version of the PSS (the “pro”) that is much more rigid on the boot. It is nearly impossible to get the amount of compression that they call for in their chart, especially by yourself, unless you have something with which to compress. In my case, me in the bilge pushing with both legs, and a buddy tightening the set screws. Someone already mentioned this, but there are two set screws in each position, and they are single use only. If you take the advice to compress the stainless collar further, replace all four screws and use a drop of the loctite they give you. Also, the pro version comes with a second stainless collar, in two halves, that gets installed forward of the main collar, after the main collar is used to compress the boot and secured. That secondary collar is to keep the main collar from working forward over time. If you have the standard version, a good hose clamp forward of the main collar can serve the same purpose. With either version, a critical item, from my own unfortunate experience—check regularly to be sure the hose that leads to the boot is getting water flow. Some of our tugs are capable of speeds that will pull water out of the boot astern, thus starving the seal and the forward Cutless bearing of water, and causing them to fail fast. In my case, that water line had clogged (mine is a takeoff from the gear oil cooler, and it clogged there)—but since the boat was in the water, the seal stayed full of water. Until I next hauled, and then it was dry, and I forgot to burp the seal when we went back in the water. I made it about an hour before both water and smoke were billowing into the boat, as the PSS and the front cutless bearing had both burned. Made it back through the locks and onto the hard again, and got to replace the Cutless bearings (aft was fine, but I was there so did it anyway). Easy to check this water flow—with engine in idle, pull the hose that attaches to the boot. Water should flow in from the boot, and also in from the hose (under pressure). Replace and check again in 6 months. In my case, I’ve now added a flow indicator in the engine room, so i can glance at that and not have to pull the hose any more. I echo others’ remarks—prop shaft needs to be straight for really any seal to work, not to mention avoiding tearing up the reduction gear… Based on other’s experience the only downside of a Tides seal is that it will wear a groove in the prop shaft, and will need to be moved around a bit if/when replaced, etc. The PSS does not have the problem. In my own experience now with both regular and Pro PSS, I have never had one mist/leak when properly installed and adjusted. As to replacement of the Cutless bearings, they are widely available (Cutless is a product/brand name) and relatively easy to work with. You carefully saw through the old one from the inside so you can roll it a bit and make it smaller to come out easier. Then freeze the new one for a few hours (or whatever you can) before installation. In my case, the stern one was much harder to install, and we ended up needing a significant hammer (10#) and steel to put across it in order to get it in all the way. Both bearings will protrude about 1/2” when fully seated. Measure/mark the new ones before they go in if you’re not sure. In my case, there were set screws (two per bearing I believe), and it took some searching to find the stern ones below 15 years of bottom paint.  :) Best of luck and ping me if I can shed any further light. OK, maybe that was more like $0.05, ha. Bennessie 37-202 

You very points, some I had not considered. I went a much cheaper route, I used an Aqua Alarm System mostly because I already had an Aqura Alarm panel on the overhead; https://aqualarm.net/index.php?main_page=product_info&cPath=5&products_id=28  https://aqualarm.net/index.php?main_page=product_info&products_id=3 
 I can add a sensor and change the panel, again. I also like this approach, but I need to order it before the tariffs triple the price. https://www.aliexpress.us/item/2251832681615967.html?spm=a2g0o.cart.0.0.78b138dakT771d&mp=1&_gl=1ipo47c_gcl_awR0NMLjE3MzY4NjY4NzguQ2owS0NRaUFzNWk4QmhEbUFSSXNBR0U0eEh6MU5XdHNiUWlQQ0F1eFJMNjRWdTFpbUhoRkFJS0Nsa3dqbF9fTFhOZU9hal95V2JZNWZza2FBaE1ZRUFMd193Y0I._gcl_dcR0NMLjE3MzY4NjY4NzguQ2owS0NRaUFzNWk4QmhEbUFSSXNBR0U0eEh6MU5XdHNiUWlQQ0F1eFJMNjRWdTFpbUhoRkFJS0Nsa3dqbF9fTFhOZU9hal95V2JZNWZza2FBaE1ZRUFMd193Y0I._gcl_auMTQ0MDk0ODAyNC4xNzMyNzE3MTcz_gaNjFiNzJiYzUtODkwYS00NjM2LWE0ZWUtMDQzZDgwZjg1NTllLjE3MDc1MDA0NzQ0MTk._ga_VED1YSGNC7*MTczODUxOTc5OC45NS4xLjE3Mzg1MTk4MDEuNTcuMC4w&gatewayAdapt=glo2usa  This sensor would read the flow rate.
William L. Bowen4393 Burnham Woods Dr.Franklin, OH 45005Voice & Fax: 513-425-9388Email: SVToybox@aol.comIn a message dated 2/2/2025 12:12:28 PM Eastern Standard Time, bmacpiper@me.com writes: 
Hi William! Yes, I have this one—it’s really simple, just a spinning paddle wheel when water is flowing. The provided barbs match the I.D. of the hose that goes to their boot barb also. Your comment re: not needing to burp the seal is kind of my point. My seal water take off is on the gear cooler, so it’s about 4 feet further along on the raw water system than where you describe yours, but the opportunity for yours to plug up is still there. Scale/etc. builds up in the small barb/take-off that goes to your PSS, regardless of where that take off happens to be tapped in to the raw water system. So—when all is well with that supply hose, you’re correct, no burping required and it will fill the PSS by itself. As soon as that hose clogs--you haul the boat and all the water drains out of the long tube between cutless bearings. You relaunch and no water is pushing into the PSS from the front because the hose is clogged. Water also can’t come in from the back because it’s now airlocked.  Then, as in my case, you end up running the PSS and the forward cutless bearing dry, and they burn up pretty fast. By checking flow on that hose to your PSS, and by burping the seal, you pre-empt the problem entirely. If you have flow from the hose you technically can let that fill the seal instead, but it’s about forming a habit patten. Plus, burping the seal gets most air out right away. As a cool aside, if you just pull the hose at the PSS for a moment when you launch, the seal self-burps and eventually water comes out the barb on the PSS, so you did both things at once! Same as before—engine running in idle, pull the hose at the PSS, water should be flowing from the hose under pressure. Once water flows out the barb (entering via the cutless bearings and the stern tube), put the hose back on and clamp it. Done. Cheers, talk soon.b 
|
| PSS Seal | Inline Sight Flow Indicatorshaftseal.com |  |

|

On Feb 2, 2025, at 07:10, SVToybox via Sentoa sentoa@lists.sentoa.org wrote:
Ben,
 Do you recall what flow sensor/meter you used. I added a flow sensor on the main water intake, and think you have a great Idea to add one on the pressurized shaft seal hose. BTW, I launch and retrieve our NT 32-287 4 times on most years ( If we get to go cruising, we have a trailer) and have never had to burp the shaft seal.  The water supply for the shaft seal on our Volvo 280 is supplied immediately after the raw water pump. NT 32-2887, 2007William L. Bowen4393 Burnham Woods Dr.Franklin, OH 45005Voice & Fax: 513-425-9388Email: SVToybox@aol.comIn a message dated 2/1/2025 5:20:19 PM Eastern Standard Time, sentoa-request@lists.sentoa.org writes: 
Date: Sat, 1 Feb 2025 14:19:57 -0800From: Ben McCafferty bmacpiper@me.comSubject: [Sentoa] Re: Cutlass Bearings & shaft sealsTo: "South East Nordic Tugs Owners' Association (SENTOA)"    sentoa@lists.sentoa.orgCc: Joe Pucciarelli jpucciarelli@sdmmetro.comMessage-ID: 99127790-01B4-4CA2-B817-A8C41AFC1D0E@me.comContent-Type: text/plain;      charset=utf-8 Adding my $.02 also. There is a new version of the PSS (the “pro”) that is much more rigid on the boot. It is nearly impossible to get the amount of compression that they call for in their chart, especially by yourself, unless you have something with which to compress. In my case, me in the bilge pushing with both legs, and a buddy tightening the set screws. Someone already mentioned this, but there are two set screws in each position, and they are single use only. If you take the advice to compress the stainless collar further, replace all four screws and use a drop of the loctite they give you. Also, the pro version comes with a second stainless collar, in two halves, that gets installed forward of the main collar, after the main collar is used to compress the boot and secured. That secondary collar is to keep the main collar from working forward over time. If you have the standard version, a good hose clamp forward of the main collar can serve the same purpose. With either version, a critical item, from my own unfortunate experience—check regularly to be sure the hose that leads to the boot is getting water flow. Some of our tugs are capable of speeds that will pull water out of the boot astern, thus starving the seal and the forward Cutless bearing of water, and causing them to fail fast. In my case, that water line had clogged (mine is a takeoff from the gear oil cooler, and it clogged there)—but since the boat was in the water, the seal stayed full of water. Until I next hauled, and then it was dry, and I forgot to burp the seal when we went back in the water. I made it about an hour before both water and smoke were billowing into the boat, as the PSS and the front cutless bearing had both burned. Made it back through the locks and onto the hard again, and got to replace the Cutless bearings (aft was fine, but I was there so did it anyway). Easy to check this water flow—with engine in idle, pull the hose that attaches to the boot. Water should flow in from the boot, and also in from the hose (under pressure). Replace and check again in 6 months. In my case, I’ve now added a flow indicator in the engine room, so i can glance at that and not have to pull the hose any more. I echo others’ remarks—prop shaft needs to be straight for really any seal to work, not to mention avoiding tearing up the reduction gear… Based on other’s experience the only downside of a Tides seal is that it will wear a groove in the prop shaft, and will need to be moved around a bit if/when replaced, etc. The PSS does not have the problem. In my own experience now with both regular and Pro PSS, I have never had one mist/leak when properly installed and adjusted. As to replacement of the Cutless bearings, they are widely available (Cutless is a product/brand name) and relatively easy to work with. You carefully saw through the old one from the inside so you can roll it a bit and make it smaller to come out easier. Then freeze the new one for a few hours (or whatever you can) before installation. In my case, the stern one was much harder to install, and we ended up needing a significant hammer (10#) and steel to put across it in order to get it in all the way. Both bearings will protrude about 1/2” when fully seated. Measure/mark the new ones before they go in if you’re not sure. In my case, there were set screws (two per bearing I believe), and it took some searching to find the stern ones below 15 years of bottom paint.  :) Best of luck and ping me if I can shed any further light. OK, maybe that was more like $0.05, ha. Bennessie 37-202 

Sentoa mailing list -- sentoa@lists.sentoa.org
To unsubscribe send an email to sentoa-leave@lists.sentoa.org

Ben makes some excellent points. I did see some material (probably in the PSS instructions or on their site) where for "slower moving boats" (at or below hull speed) like most Tug owners normally do, you don't need the cooling water hose to be connected to the PSS, just a hose used for "air breathing", and the appropriate mounting setup. However, due to the fact that NT's can and should periodically be run at 75-100% throttle, this cooling hose must be connected to the PSS for NT's.
Ben's suggested test (combined with "burping" at the same time) is an excellent idea and doing regular complete raw water cooling system maintenance should also help ensure a steady, reliable supply of cooling water.
Best,
Tom Easterbrook
formerly Pilitak NT 37-068

From: Ben McCafferty via Sentoa sentoa@lists.sentoa.org
Sent: February 2, 2025 9:12 AM
To: SVToybox svtoybox@aol.com; South East Nordic Tugs Owners' Association (SENTOA) sentoa@lists.sentoa.org
Cc: Ben McCafferty bmacpiper@me.com
Subject: [Sentoa] Re: Burping the Shaft Seal

Hi William!

Yes, I have this one—it’s really simple, just a spinning paddle wheel when water is flowing. The provided barbs match the I.D. of the hose that goes to their boot barb also.

Your comment re: not needing to burp the seal is kind of my point. My seal water take off is on the gear cooler, so it’s about 4 feet further along on the raw water system than where you describe yours, but the opportunity for yours to plug up is still there. Scale/etc. builds up in the small barb/take-off that goes to your PSS, regardless of where that take off happens to be tapped in to the raw water system.

So—when all is well with that supply hose, you’re correct, no burping required and it will fill the PSS by itself. As soon as that hose clogs--you haul the boat and all the water drains out of the long tube between cutless bearings. You relaunch and no water is pushing into the PSS from the front because the hose is clogged. Water also can’t come in from the back because it’s now airlocked.

Then, as in my case, you end up running the PSS and the forward cutless bearing dry, and they burn up pretty fast.

By checking flow on that hose to your PSS, and by burping the seal, you pre-empt the problem entirely.

If you have flow from the hose you technically can let that fill the seal instead, but it’s about forming a habit patten. Plus, burping the seal gets most air out right away.

As a cool aside, if you just pull the hose at the PSS for a moment when you launch, the seal self-burps and eventually water comes out the barb on the PSS, so you did both things at once! Same as before—engine running in idle, pull the hose at the PSS, water should be flowing from the hose under pressure. Once water flows out the barb (entering via the cutless bearings and the stern tube), put the hose back on and clamp it. Done.

Cheers, talk soon.
b

https://www.shaftseal.com/marine/flow-indicator.html
PSS Seal | Inline Sight Flow Indicatorhttps://www.shaftseal.com/marine/flow-indicator.html
shaftseal.comhttps://www.shaftseal.com/marine/flow-indicator.html
[apple-touch-icon.png]https://www.shaftseal.com/marine/flow-indicator.html

On Feb 2, 2025, at 07:10, SVToybox via Sentoa sentoa@lists.sentoa.org wrote:

Ben,

Do you recall what flow sensor/meter you used. I added a flow sensor on the main water intake, and think you have a great Idea to add one on the pressurized shaft seal hose. BTW, I launch and retrieve our NT 32-287 4 times on most years ( If we get to go cruising, we have a trailer) and have never had to burp the shaft seal.  The water supply for the shaft seal on our Volvo 280 is supplied immediately after the raw water pump.

NT 32-2887, 2007
William L. Bowen
4393 Burnham Woods Dr.
Franklin, OH 45005
Voice & Fax: 513-425-9388
Email: SVToybox@aol.com
In a message dated 2/1/2025 5:20:19 PM Eastern Standard Time, sentoa-request@lists.sentoa.org writes:

Date: Sat, 1 Feb 2025 14:19:57 -0800
From: Ben McCafferty <bmacpiper@me.commailto:bmacpiper@me.com>
Subject: [Sentoa] Re: Cutlass Bearings & shaft seals
To: "South East Nordic Tugs Owners' Association (SENTOA)"
<sentoa@lists.sentoa.orgmailto:sentoa@lists.sentoa.org>
Cc: Joe Pucciarelli <jpucciarelli@sdmmetro.commailto:jpucciarelli@sdmmetro.com>
Message-ID: <99127790-01B4-4CA2-B817-A8C41AFC1D0E@me.commailto:99127790-01B4-4CA2-B817-A8C41AFC1D0E@me.com>
Content-Type: text/plain;      charset=utf-8

Adding my $.02 also. There is a new version of the PSS (the “pro”) that is much more rigid on the boot. It is nearly impossible to get the amount of compression that they call for in their chart, especially by yourself, unless you have something with which to compress. In my case, me in the bilge pushing with both legs, and a buddy tightening the set screws.

Someone already mentioned this, but there are two set screws in each position, and they are single use only. If you take the advice to compress the stainless collar further, replace all four screws and use a drop of the loctite they give you.

Also, the pro version comes with a second stainless collar, in two halves, that gets installed forward of the main collar, after the main collar is used to compress the boot and secured. That secondary collar is to keep the main collar from working forward over time. If you have the standard version, a good hose clamp forward of the main collar can serve the same purpose.

With either version, a critical item, from my own unfortunate experience—check regularly to be sure the hose that leads to the boot is getting water flow. Some of our tugs are capable of speeds that will pull water out of the boot astern, thus starving the seal and the forward Cutless bearing of water, and causing them to fail fast.

In my case, that water line had clogged (mine is a takeoff from the gear oil cooler, and it clogged there)—but since the boat was in the water, the seal stayed full of water. Until I next hauled, and then it was dry, and I forgot to burp the seal when we went back in the water. I made it about an hour before both water and smoke were billowing into the boat, as the PSS and the front cutless bearing had both burned. Made it back through the locks and onto the hard again, and got to replace the Cutless bearings (aft was fine, but I was there so did it anyway).

Easy to check this water flow—with engine in idle, pull the hose that attaches to the boot. Water should flow in from the boot, and also in from the hose (under pressure). Replace and check again in 6 months. In my case, I’ve now added a flow indicator in the engine room, so i can glance at that and not have to pull the hose any more.

I echo others’ remarks—prop shaft needs to be straight for really any seal to work, not to mention avoiding tearing up the reduction gear…

Based on other’s experience the only downside of a Tides seal is that it will wear a groove in the prop shaft, and will need to be moved around a bit if/when replaced, etc. The PSS does not have the problem.

In my own experience now with both regular and Pro PSS, I have never had one mist/leak when properly installed and adjusted.

As to replacement of the Cutless bearings, they are widely available (Cutless is a product/brand name) and relatively easy to work with. You carefully saw through the old one from the inside so you can roll it a bit and make it smaller to come out easier. Then freeze the new one for a few hours (or whatever you can) before installation. In my case, the stern one was much harder to install, and we ended up needing a significant hammer (10#) and steel to put across it in order to get it in all the way. Both bearings will protrude about 1/2” when fully seated. Measure/mark the new ones before they go in if you’re not sure.

In my case, there were set screws (two per bearing I believe), and it took some searching to find the stern ones below 15 years of bottom paint.  :)

Best of luck and ping me if I can shed any further light. OK, maybe that was more like $0.05, ha.

Ben
nessie 37-202

Sentoa mailing list -- sentoa@lists.sentoa.org
To unsubscribe send an email to sentoa-leave@lists.sentoa.org