Cutlass Bearings & shaft seals
Hi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it
had done around 1100 hours. As far as I'm aware the cutlass bearings have
never been replaced. The boat is in salt water which can be a bit silty on
the UK east coast. No undue vibration when going forward, but a bit grumbly
in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in
2019, whilst the seal does not leak per se, I do get the messy black mist
spray that covers the area around the seal.
So, 2 questions:
- Have I gone beyond what would be a reasonable length of time / hours to
change the bearings? (Does anybody have details of suitable replacements?) - Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS
and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
We have had PSS shaft seals on both of our boats and have replaced both due to age, but not leaks or failures. The PSS seal should not "mist" or leak.
Watch the shaft rotating--engine running at idle speed--the PSS seal should not show any run-out (wobbling, if you will). The Nordic Tugs have two cutless bearings, and are not likely to exibit wear for many thousands of hours. (Our NT 32-238 has 5,788 hours on the original cutless bearings). But, a mis-aligned or bent propellor shaft, worn or failed engine mounts or such could indeed cause premature wear of the cutless bearings and could also contribute to your PSS "misting" problem.
First, try flushing the seal by simply prying the rotating and stationary parts apart with your fingers. Insert a piece of paper or thin gasket material between the teo pieces and rotate the shaft a few times to wipe clean the seaqling surfaces. If still "misting" try compressing the bellows a bit more by removing the grub screws (there should be two in each threaded hole!) and moving the stainless steel rotor closer to the carbon seal--perhaps 12mm will do.
Good luck on solving your problem.
Harry Hungate
Bessie NT 32-238
Atlantic Beach, Florida
On Feb 1, 2025, at 12:23 PM, Steve Day via Sentoa sentoa@lists.sentoa.org wrote:
Hi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it had done around 1100 hours. As far as I'm aware the cutlass bearings have never been replaced. The boat is in salt water which can be a bit silty on the UK east coast. No undue vibration when going forward, but a bit grumbly in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in 2019, whilst the seal does not leak per se, I do get the messy black mist spray that covers the area around the seal.
So, 2 questions:
- Have I gone beyond what would be a reasonable length of time / hours to change the bearings? (Does anybody have details of suitable replacements?)
- Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
Sentoa mailing list -- sentoa@lists.sentoa.org
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I switched ours to a Tideseal 4 years ago and we are very happy with the totally dry bilge.
-Evan
NT 37-148
Tugaway
Victoria, BC
On Feb 1, 2025, at 09:23, Steve Day via Sentoa sentoa@lists.sentoa.org wrote:
Hi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it had done around 1100 hours. As far as I'm aware the cutlass bearings have never been replaced. The boat is in salt water which can be a bit silty on the UK east coast. No undue vibration when going forward, but a bit grumbly in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in 2019, whilst the seal does not leak per se, I do get the messy black mist spray that covers the area around the seal.
So, 2 questions:
- Have I gone beyond what would be a reasonable length of time / hours to change the bearings? (Does anybody have details of suitable replacements?)
- Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
Sentoa mailing list -- sentoa@lists.sentoa.org
To unsubscribe send an email to sentoa-leave@lists.sentoa.org
The last time I had my PSS shaft seal replaced, after a year or so, it began to spray/leak at medium to high rpm.
On the PSS website, I found a table showing how much compression should be put on my seal, and discovered I needed to increase the compression a full inch.
I did so, and all spray/leakage disappeared at all rpms. Apparently the seal was not properly compressed when it was replaced. So, you might want to go to the website and get the compression for your seal and check it. The table is here: https://www.shaftseal.com/marine/pss-type-a-seal.html
On Feb 1, 2025, at 12:23 PM, Steve Day via Sentoa sentoa@lists.sentoa.org wrote:
Hi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it had done around 1100 hours. As far as I'm aware the cutlass bearings have never been replaced. The boat is in salt water which can be a bit silty on the UK east coast. No undue vibration when going forward, but a bit grumbly in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in 2019, whilst the seal does not leak per se, I do get the messy black mist spray that covers the area around the seal.
So, 2 questions:
- Have I gone beyond what would be a reasonable length of time / hours to change the bearings? (Does anybody have details of suitable replacements?)
- Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
Sentoa mailing list -- sentoa@lists.sentoa.org
To unsubscribe send an email to sentoa-leave@lists.sentoa.org
Hi Steve,
I agree with some of the others regarding the proper installation and adjustment of the PSS seal. Mine did not leak. However, they do require periodic inspection and adjustment (may not need adjustment, but should be inspected). However, a lot of owners do like their Tides "lip seal" shaft seals. Personal preference, I would think.
I replaced my cutlass bearings and the rudder seal at the same time as I did the regular "replacement/maintenance" of my PSS seal. I also sent the prop into the shop for a "tune up". The extra time and labour was minimal as far as removing the rudder, prop, cutlass bearings and shaft, and on the "boat scale" of expenses, the additional parts were also minimal, giving an end result of "near new". The prop shop costs were the largest component of the "additonal" expense, but I felt worth it, as I did take some pitch out of the prop to ensure that the engine under load would meet rated RPM's so as to avoid "overload". At the time, Pilitak was about 17-18 years old. I upgraded to the "Pro" version of the PSS bellows, giving a 10 year life before the next recommended replacement, and I did not feel it was prudent to leave in 18 year old cutlass bearings and a rudder seal (until they were 28 years old).
There is a great article on SENTOA about this very project (for a NT37) outlining steps and parts (I think written by Stephen Hill).
Good luck,
Tom Easterbrook
formerly Pilitak NT 37-068
From: Steve Day via Sentoa sentoa@lists.sentoa.org
Sent: February 1, 2025 9:23 AM
To: South East Nordic Tugs Owners' Association (SENTOA) sentoa@lists.sentoa.org
Cc: Steve Day s.day2905@gmail.com
Subject: [Sentoa] Cutlass Bearings & shaft seals
Hi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it had done around 1100 hours. As far as I'm aware the cutlass bearings have never been replaced. The boat is in salt water which can be a bit silty on the UK east coast. No undue vibration when going forward, but a bit grumbly in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in 2019, whilst the seal does not leak per se, I do get the messy black mist spray that covers the area around the seal.
So, 2 questions:
- Have I gone beyond what would be a reasonable length of time / hours to change the bearings? (Does anybody have details of suitable replacements?)
- Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
Hi Steve,
Hope you are having really good luck with SINBAD in the yard over there in the UK.
We’re on our 3rd PSS shaft seal and happy enough with the product’s performance to keep using them. Like others here, we switched to PYI’s ‘Pro’ version with the silicon bellows and the shaft retaining collar (clamp) because of the petroleum resistance in addition to the longer service interval - we have a PTO hydraulic pump/tank/controls with lots of high pressure hoses sharing that salon bilge (running our bow thruster, davit and deck reel for the anchor rode).
We experienced similar frustration struggling to achieve the full 1” pre-load compression on the Pro seal’s very stiff silicon bellows. I found it so difficult the first time, I too wondered if many yards would work that hard to actually do it properly, or if “some” compression is considered good enough. So I made a pair of tools to get exactly 1” of compression.
So the following is more for others to track down in the blog archive than for your efforts Steve:
Starting with a 6”x12” piece of ½” starboard (HPTE) temporally attached to the face of a ~20” piece of 2x6 (for table saw ripping safety); “bevel rip” part of one face along the long edge into an approx 2” tall, 15-20 degree uniform bevel until what was one of the long ½”edges is now near sharp (you could do this with a belt sander too but you need the bevels to be very uniform ); you want the finish on these beveled faces to be as smooth as possible without any chattering saw marks because these are going to be the hard working surfaces; discard the 2x6; cut the starboard into two 6”x6” pieces; drill a 2.25” hole in the middle of each; extend the hole to be a 2.25” slot, opening from the tapered edge (so as to be able to slide each sharp, forked edge of the 6x6 tool easily over a 2” shaft).
After all the new shaft seal components are installed and well soap/glycerin lubricated, the Pro’s stiff silicon bellows is ready to compress (and with the shaft coupling already attached and fully torqued to the marine gear!). I start by temporarily tightening the shaft retention clamp from the Pro kit snug to the forward face of the loose S/S rotor which is snug to the carbon stator attached to the silicon bellows.
Then while rotating/wiggling the rotor in one hand to start to compress the bellows, you can then carefully sneak the first tapered 6x6 forked tool in between the S/S rotor and temporarily fixed retention clamp until the tapered edged forked tips emerges on the other side and the ½” parallel faces of the starboard is uniformly spreading the rotor and the clamp. You are half way there, but it’s the easy half.
To insert the second tool, rotate the shaft 180; then, with forked tapered tool face against forked tapered tool face, work/wiggle/slide/cuss the S/S rotor to further compress the bellows in order to get the tapered face of the 2nd tool started in against the tapered face of the first tool, then carefully tap the butt end of each of the 6x6 tools farther and farther together onto the shaft until enough of the 1/2" thick 6x6 tools stack up face to face to get your 1” of pre-compression.
Then of course, follow the rest of the install procedure locking down the S/S rotor with the doubled-up thread-locked cupped set-screws before loosening the shaft clamp to remove the two 6x6 tools, then relocate the shaft retention clamp to its intended snug position against the now locked S/S rotor.
I haven't tried this but this entire process will likely work for achieving the 1" compression on the bellows with PYI's regular type "A" shaft seal if you also get PYI's expensive 2" shaft retention collar/clamp or a suitable equivalent like a 2" shaft zinc.
Additionally, I will strongly encourage anyone DIYing their shaft seal to follow Stephen Hill’s great advice from his outstanding 2017 cutlass/shaft seal article (see SENTOA/Maintenance) and specifically to REPLACE those stock hex-head bolts connecting the shaft coupling flange to the marine gear with Grade 8, 5/8”-18 x 2-1/4” socket head (allen) cap bolts (I wasn’t able to find 2-1/4” in grade 8 so used 2-1/2” along with grinder modified 1/8” thick, 5/8” head bolt washers under the allen heads). Removes a lot of frustration and makes achieving the correct torque a whole lot easier using a male allen socket instead of struggling with 2 wrenches in a tight part of your engine room.
Good luck!
Kelly Britz, SANDPIPER, NT37-042
Edmonds/Seattle, WA
From: Steve Day via Sentoa sentoa@lists.sentoa.org
Sent: Saturday, February 1, 2025 9:23 AM
To: South East Nordic Tugs Owners' Association (SENTOA) sentoa@lists.sentoa.org
Cc: Steve Day s.day2905@gmail.com
Subject: [Sentoa] Cutlass Bearings & shaft seals
Hi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it had done around 1100 hours. As far as I'm aware the cutlass bearings have never been replaced. The boat is in salt water which can be a bit silty on the UK east coast. No undue vibration when going forward, but a bit grumbly in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in 2019, whilst the seal does not leak per se, I do get the messy black mist spray that covers the area around the seal.
So, 2 questions:
- Have I gone beyond what would be a reasonable length of time / hours to change the bearings? (Does anybody have details of suitable replacements?)
- Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
Here’s what I made to do the compression:
It clamps onto the shaft, and you turn the three set screws slowly and evenly to compress the bellows.
On Feb 10, 2025, at 6:34 PM, Kelly Britz via Sentoa sentoa@lists.sentoa.org wrote:
Hi Steve,
Hope you are having really good luck with SINBAD in the yard over there in the UK.
We’re on our 3rd PSS shaft seal and happy enough with the product’s performance to keep using them. Like others here, we switched to PYI’s ‘Pro’ version with the silicon bellows and the shaft retaining collar (clamp) because of the petroleum resistance in addition to the longer service interval - we have a PTO hydraulic pump/tank/controls with lots of high pressure hoses sharing that salon bilge (running our bow thruster, davit and deck reel for the anchor rode).
We experienced similar frustration struggling to achieve the full 1” pre-load compression on the Pro seal’s very stiff silicon bellows. I found it so difficult the first time, I too wondered if many yards would work that hard to actually do it properly, or if “some” compression is considered good enough. So I made a pair of tools to get exactly 1” of compression.
So the following is more for others to track down in the blog archive than for your efforts Steve:
Starting with a 6”x12” piece of ½” starboard (HPTE) temporally attached to the face of a ~20” piece of 2x6 (for table saw ripping safety); “bevel rip” part of one face along the long edge into an approx 2” tall, 15-20 degree uniform bevel until what was one of the long ½”edges is now near sharp (you could do this with a belt sander too but you need the bevels to be very uniform ); you want the finish on these beveled faces to be as smooth as possible without any chattering saw marks because these are going to be the hard working surfaces; discard the 2x6; cut the starboard into two 6”x6” pieces; drill a 2.25” hole in the middle of each; extend the hole to be a 2.25” slot, opening from the tapered edge (so as to be able to slide each sharp, forked edge of the 6x6 tool easily over a 2” shaft).
After all the new shaft seal components are installed and well soap/glycerin lubricated, the Pro’s stiff silicon bellows is ready to compress (and with the shaft coupling already attached and fully torqued to the marine gear!). I start by temporarily tightening the shaft retention clamp from the Pro kit snug to the forward face of the loose S/S rotor which is snug to the carbon stator attached to the silicon bellows.
Then while rotating/wiggling the rotor in one hand to start to compress the bellows, you can then carefully sneak the first tapered 6x6 forked tool in between the S/S rotor and temporarily fixed retention clamp until the tapered edged forked tips emerges on the other side and the ½” parallel faces of the starboard is uniformly spreading the rotor and the clamp. You are half way there, but it’s the easy half.
To insert the second tool, rotate the shaft 180; then, with forked tapered tool face against forked tapered tool face, work/wiggle/slide/cuss the S/S rotor to further compress the bellows in order to get the tapered face of the 2nd tool started in against the tapered face of the first tool, then carefully tap the butt end of each of the 6x6 tools farther and farther together onto the shaft until enough of the 1/2" thick 6x6 tools stack up face to face to get your 1” of pre-compression.
Then of course, follow the rest of the install procedure locking down the S/S rotor with the doubled-up thread-locked cupped set-screws before loosening the shaft clamp to remove the two 6x6 tools, then relocate the shaft retention clamp to its intended snug position against the now locked S/S rotor.
I haven't tried this but this entire process will likely work for achieving the 1" compression on the bellows with PYI's regular type "A" shaft seal if you also get PYI's expensive 2" shaft retention collar/clamp or a suitable equivalent like a 2" shaft zinc.
Additionally, I will strongly encourage anyone DIYing their shaft seal to follow Stephen Hill’s great advice from his outstanding 2017 cutlass/shaft seal article (see SENTOA/Maintenance) and specifically to REPLACE those stock hex-head bolts connecting the shaft coupling flange to the marine gear with Grade 8, 5/8”-18 x 2-1/4” socket head (allen) cap bolts (I wasn’t able to find 2-1/4” in grade 8 so used 2-1/2” along with grinder modified 1/8” thick, 5/8” head bolt washers under the allen heads). Removes a lot of frustration and makes achieving the correct torque a whole lot easier using a male allen socket instead of struggling with 2 wrenches in a tight part of your engine room.
Good luck!
Kelly Britz, SANDPIPER, NT37-042
Edmonds/Seattle, WA
From: Steve Day via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org>
Sent: Saturday, February 1, 2025 9:23 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org>
Cc: Steve Day <s.day2905@gmail.com mailto:s.day2905@gmail.com>
Subject: [Sentoa] Cutlass Bearings & shaft seals
Hi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it had done around 1100 hours. As far as I'm aware the cutlass bearings have never been replaced. The boat is in salt water which can be a bit silty on the UK east coast. No undue vibration when going forward, but a bit grumbly in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in 2019, whilst the seal does not leak per se, I do get the messy black mist spray that covers the area around the seal.
So, 2 questions:
- Have I gone beyond what would be a reasonable length of time / hours to change the bearings? (Does anybody have details of suitable replacements?)
- Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
Sentoa mailing list -- sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org
To unsubscribe send an email to sentoa-leave@lists.sentoa.org mailto:sentoa-leave@lists.sentoa.org
love it!
From: sadler love via Sentoa sentoa@lists.sentoa.org
Sent: Tuesday, February 11, 2025 5:56 AM
To: South East Nordic Tugs Owners' Association (SENTOA) sentoa@lists.sentoa.org
Cc: sadler love sadlerl@me.com
Subject: [Sentoa] Re: ...a tool to compress the stiff bellows on the PYI Pro shaft seals
Here’s what I made to do the compression: [cid:DF6D761D-6545-48DA-85EA-8C06D5181CF2] [cid:C54D1E9C-6AE3-464A-B101-895A302A2033]
It clamps onto the shaft, and you turn the three set screws slowly and evenly to compress the bellows.
On Feb 10, 2025, at 6:34 PM, Kelly Britz via Sentoa <sentoa@lists.sentoa.orgmailto:sentoa@lists.sentoa.org> wrote:
Hi Steve,
Hope you are having really good luck with SINBAD in the yard over there in the UK.
We’re on our 3rd PSS shaft seal and happy enough with the product’s performance to keep using them. Like others here, we switched to PYI’s ‘Pro’ version with the silicon bellows and the shaft retaining collar (clamp) because of the petroleum resistance in addition to the longer service interval - we have a PTO hydraulic pump/tank/controls with lots of high pressure hoses sharing that salon bilge (running our bow thruster, davit and deck reel for the anchor rode).
We experienced similar frustration struggling to achieve the full 1” pre-load compression on the Pro seal’s very stiff silicon bellows. I found it so difficult the first time, I too wondered if many yards would work that hard to actually do it properly, or if “some” compression is considered good enough. So I made a pair of tools to get exactly 1” of compression.
So the following is more for others to track down in the blog archive than for your efforts Steve:
Starting with a 6”x12” piece of ½” starboard (HPTE) temporally attached to the face of a ~20” piece of 2x6 (for table saw ripping safety); “bevel rip” part of one face along the long edge into an approx 2” tall, 15-20 degree uniform bevel until what was one of the long ½”edges is now near sharp (you could do this with a belt sander too but you need the bevels to be very uniform ); you want the finish on these beveled faces to be as smooth as possible without any chattering saw marks because these are going to be the hard working surfaces; discard the 2x6; cut the starboard into two 6”x6” pieces; drill a 2.25” hole in the middle of each; extend the hole to be a 2.25” slot, opening from the tapered edge (so as to be able to slide each sharp, forked edge of the 6x6 tool easily over a 2” shaft).
After all the new shaft seal components are installed and well soap/glycerin lubricated, the Pro’s stiff silicon bellows is ready to compress (and with the shaft coupling already attached and fully torqued to the marine gear!). I start by temporarily tightening the shaft retention clamp from the Pro kit snug to the forward face of the loose S/S rotor which is snug to the carbon stator attached to the silicon bellows.
Then while rotating/wiggling the rotor in one hand to start to compress the bellows, you can then carefully sneak the first tapered 6x6 forked tool in between the S/S rotor and temporarily fixed retention clamp until the tapered edged forked tips emerges on the other side and the ½” parallel faces of the starboard is uniformly spreading the rotor and the clamp. You are half way there, but it’s the easy half.
To insert the second tool, rotate the shaft 180; then, with forked tapered tool face against forked tapered tool face, work/wiggle/slide/cuss the S/S rotor to further compress the bellows in order to get the tapered face of the 2nd tool started in against the tapered face of the first tool, then carefully tap the butt end of each of the 6x6 tools farther and farther together onto the shaft until enough of the 1/2" thick 6x6 tools stack up face to face to get your 1” of pre-compression.
Then of course, follow the rest of the install procedure locking down the S/S rotor with the doubled-up thread-locked cupped set-screws before loosening the shaft clamp to remove the two 6x6 tools, then relocate the shaft retention clamp to its intended snug position against the now locked S/S rotor.
I haven't tried this but this entire process will likely work for achieving the 1" compression on the bellows with PYI's regular type "A" shaft seal if you also get PYI's expensive 2" shaft retention collar/clamp or a suitable equivalent like a 2" shaft zinc.
Additionally, I will strongly encourage anyone DIYing their shaft seal to follow Stephen Hill’s great advice from his outstanding 2017 cutlass/shaft seal article (see SENTOA/Maintenance) and specifically to REPLACE those stock hex-head bolts connecting the shaft coupling flange to the marine gear with Grade 8, 5/8”-18 x 2-1/4” socket head (allen) cap bolts (I wasn’t able to find 2-1/4” in grade 8 so used 2-1/2” along with grinder modified 1/8” thick, 5/8” head bolt washers under the allen heads). Removes a lot of frustration and makes achieving the correct torque a whole lot easier using a male allen socket instead of struggling with 2 wrenches in a tight part of your engine room.
Good luck!
Kelly Britz, SANDPIPER, NT37-042
Edmonds/Seattle, WA
From: Steve Day via Sentoa <sentoa@lists.sentoa.orgmailto:sentoa@lists.sentoa.org>
Sent: Saturday, February 1, 2025 9:23 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.orgmailto:sentoa@lists.sentoa.org>
Cc: Steve Day <s.day2905@gmail.commailto:s.day2905@gmail.com>
Subject: [Sentoa] Cutlass Bearings & shaft seals
Hi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it had done around 1100 hours. As far as I'm aware the cutlass bearings have never been replaced. The boat is in salt water which can be a bit silty on the UK east coast. No undue vibration when going forward, but a bit grumbly in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in 2019, whilst the seal does not leak per se, I do get the messy black mist spray that covers the area around the seal.
So, 2 questions:
- Have I gone beyond what would be a reasonable length of time / hours to change the bearings? (Does anybody have details of suitable replacements?)
- Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
Sentoa mailing list -- sentoa@lists.sentoa.orgmailto:sentoa@lists.sentoa.org
To unsubscribe send an email to sentoa-leave@lists.sentoa.orgmailto:sentoa-leave@lists.sentoa.org
Impressive strategies & innovations…
Or you just get a TideSeal and simplify things.
No leak, little to no maintenance & a backup seal is easily ready to install if the original wears out.
I would not willingly go back to the fiddle & futz of a PSS.
-evan
NT37-148
TUGAWAY
Sent from my iPhone
(please excuse the typos...)
On Feb 11, 2025, at 05:57, sadler love via Sentoa <sentoa@lists.sentoa.org> wrote:
Here’s what I made to do the compression: <IMG_1525.jpeg>
<IMG_1524.jpeg>
It clamps onto the shaft, and you turn the three set screws slowly and evenly to compress the bellows.
On Feb 10, 2025, at 6:34 PM, Kelly Britz via Sentoa <sentoa@lists.sentoa.org> wrote:
Hi Steve,
Hope you are having really good luck with SINBAD in the yard over there in the UK.
We’re on our 3rd PSS shaft seal and happy enough with the product’s performance to keep using them. Like others here, we switched to PYI’s ‘Pro’ version with the silicon bellows and the shaft retaining collar (clamp) because of the petroleum resistance in addition to the longer service interval - we have a PTO hydraulic pump/tank/controls with lots of high pressure hoses sharing that salon bilge (running our bow thruster, davit and deck reel for the anchor rode).
We experienced similar frustration struggling to achieve the full 1” pre-load compression on the Pro seal’s very stiff silicon bellows. I found it so difficult the first time, I too wondered if many yards would work that hard to actually do it properly, or if “some” compression is considered good enough. So I made a pair of tools to get exactly 1” of compression.
So the following is more for others to track down in the blog archive than for your efforts Steve:
Starting with a 6”x12” piece of ½” starboard (HPTE) temporally attached to the face of a ~20” piece of 2x6 (for table saw ripping safety); “bevel rip” part of one face along the long edge into an approx 2” tall, 15-20 degree uniform bevel until what was one of the long ½”edges is now near sharp (you could do this with a belt sander too but you need the bevels to be very uniform ); you want the finish on these beveled faces to be as smooth as possible without any chattering saw marks because these are going to be the hard working surfaces; discard the 2x6; cut the starboard into two 6”x6” pieces; drill a 2.25” hole in the middle of each; extend the hole to be a 2.25” slot, opening from the tapered edge (so as to be able to slide each sharp, forked edge of the 6x6 tool easily over a 2” shaft).
After all the new shaft seal components are installed and well soap/glycerin lubricated, the Pro’s stiff silicon bellows is ready to compress (and with the shaft coupling already attached and fully torqued to the marine gear!). I start by temporarily tightening the shaft retention clamp from the Pro kit snug to the forward face of the loose S/S rotor which is snug to the carbon stator attached to the silicon bellows.
Then while rotating/wiggling the rotor in one hand to start to compress the bellows, you can then carefully sneak the first tapered 6x6 forked tool in between the S/S rotor and temporarily fixed retention clamp until the tapered edged forked tips emerges on the other side and the ½” parallel faces of the starboard is uniformly spreading the rotor and the clamp. You are half way there, but it’s the easy half.
To insert the second tool, rotate the shaft 180; then, with forked tapered tool face against forked tapered tool face, work/wiggle/slide/cuss the S/S rotor to further compress the bellows in order to get the tapered face of the 2nd tool started in against the tapered face of the first tool, then carefully tap the butt end of each of the 6x6 tools farther and farther together onto the shaft until enough of the 1/2" thick 6x6 tools stack up face to face to get your 1” of pre-compression.
Then of course, follow the rest of the install procedure locking down the S/S rotor with the doubled-up thread-locked cupped set-screws before loosening the shaft clamp to remove the two 6x6 tools, then relocate the shaft retention clamp to its intended snug position against the now locked S/S rotor.
I haven't tried this but this entire process will likely work for achieving the 1" compression on the bellows with PYI's regular type "A" shaft seal if you also get PYI's expensive 2" shaft retention collar/clamp or a suitable equivalent like a 2" shaft zinc.
Additionally, I will strongly encourage anyone DIYing their shaft seal to follow Stephen Hill’s great advice from his outstanding 2017 cutlass/shaft seal article (see SENTOA/Maintenance) and specifically to REPLACE those stock hex-head bolts connecting the shaft coupling flange to the marine gear with Grade 8, 5/8”-18 x 2-1/4” socket head (allen) cap bolts (I wasn’t able to find 2-1/4” in grade 8 so used 2-1/2” along with grinder modified 1/8” thick, 5/8” head bolt washers under the allen heads). Removes a lot of frustration and makes achieving the correct torque a whole lot easier using a male allen socket instead of struggling with 2 wrenches in a tight part of your engine room.
Good luck!
Kelly Britz, SANDPIPER, NT37-042
Edmonds/Seattle, WA
From: Steve Day via Sentoa <sentoa@lists.sentoa.org>
Sent: Saturday, February 1, 2025 9:23 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.org>
Cc: Steve Day <s.day2905@gmail.com>
Subject: [Sentoa] Cutlass Bearings & shaft sealsHi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it had done around 1100 hours. As far as I'm aware the cutlass bearings have never been replaced. The boat is in salt water which can be a bit silty on the UK east coast. No undue vibration when going forward, but a bit grumbly in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in 2019, whilst the seal does not leak per se, I do get the messy black mist spray that covers the area around the seal.
So, 2 questions:
Have I gone beyond what would be a reasonable length of time / hours to change the bearings? (Does anybody have details of suitable replacements?)
Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
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I would get a patent on that right away. It would be super easy for that to be integrated to the forward clamp. Install the Bellows and stainless collar, add the forward clamp. Screw the compression screws down an inch, tighten the set screws on the stainless collar. Done. The clamp would stay in place in order to ensure no movement of the stainless collar. Or, back the compression screws off all the way, and move the clamp aft to meet the stainless color. Either would work beautifully.b
P. S. With me stuffed in the bilge, pushing on the collar with both feet, we were able to get 3/4 of an inch of compression instead of 1, and so far that has been enough. No leaks. Fingers crossed.
;)
Sent from my iPhone
On Feb 11, 2025, at 05:57, sadler love via Sentoa <sentoa@lists.sentoa.org> wrote:
Here’s what I made to do the compression: <IMG_1525.jpeg>
<IMG_1524.jpeg>
It clamps onto the shaft, and you turn the three set screws slowly and evenly to compress the bellows.
On Feb 10, 2025, at 6:34 PM, Kelly Britz via Sentoa <sentoa@lists.sentoa.org> wrote:
Hi Steve,
Hope you are having really good luck with SINBAD in the yard over there in the UK.
We’re on our 3rd PSS shaft seal and happy enough with the product’s performance to keep using them. Like others here, we switched to PYI’s ‘Pro’ version with the silicon bellows and the shaft retaining collar (clamp) because of the petroleum resistance in addition to the longer service interval - we have a PTO hydraulic pump/tank/controls with lots of high pressure hoses sharing that salon bilge (running our bow thruster, davit and deck reel for the anchor rode).
We experienced similar frustration struggling to achieve the full 1” pre-load compression on the Pro seal’s very stiff silicon bellows. I found it so difficult the first time, I too wondered if many yards would work that hard to actually do it properly, or if “some” compression is considered good enough. So I made a pair of tools to get exactly 1” of compression.
So the following is more for others to track down in the blog archive than for your efforts Steve:
Starting with a 6”x12” piece of ½” starboard (HPTE) temporally attached to the face of a ~20” piece of 2x6 (for table saw ripping safety); “bevel rip” part of one face along the long edge into an approx 2” tall, 15-20 degree uniform bevel until what was one of the long ½”edges is now near sharp (you could do this with a belt sander too but you need the bevels to be very uniform ); you want the finish on these beveled faces to be as smooth as possible without any chattering saw marks because these are going to be the hard working surfaces; discard the 2x6; cut the starboard into two 6”x6” pieces; drill a 2.25” hole in the middle of each; extend the hole to be a 2.25” slot, opening from the tapered edge (so as to be able to slide each sharp, forked edge of the 6x6 tool easily over a 2” shaft).
After all the new shaft seal components are installed and well soap/glycerin lubricated, the Pro’s stiff silicon bellows is ready to compress (and with the shaft coupling already attached and fully torqued to the marine gear!). I start by temporarily tightening the shaft retention clamp from the Pro kit snug to the forward face of the loose S/S rotor which is snug to the carbon stator attached to the silicon bellows.
Then while rotating/wiggling the rotor in one hand to start to compress the bellows, you can then carefully sneak the first tapered 6x6 forked tool in between the S/S rotor and temporarily fixed retention clamp until the tapered edged forked tips emerges on the other side and the ½” parallel faces of the starboard is uniformly spreading the rotor and the clamp. You are half way there, but it’s the easy half.
To insert the second tool, rotate the shaft 180; then, with forked tapered tool face against forked tapered tool face, work/wiggle/slide/cuss the S/S rotor to further compress the bellows in order to get the tapered face of the 2nd tool started in against the tapered face of the first tool, then carefully tap the butt end of each of the 6x6 tools farther and farther together onto the shaft until enough of the 1/2" thick 6x6 tools stack up face to face to get your 1” of pre-compression.
Then of course, follow the rest of the install procedure locking down the S/S rotor with the doubled-up thread-locked cupped set-screws before loosening the shaft clamp to remove the two 6x6 tools, then relocate the shaft retention clamp to its intended snug position against the now locked S/S rotor.
I haven't tried this but this entire process will likely work for achieving the 1" compression on the bellows with PYI's regular type "A" shaft seal if you also get PYI's expensive 2" shaft retention collar/clamp or a suitable equivalent like a 2" shaft zinc.
Additionally, I will strongly encourage anyone DIYing their shaft seal to follow Stephen Hill’s great advice from his outstanding 2017 cutlass/shaft seal article (see SENTOA/Maintenance) and specifically to REPLACE those stock hex-head bolts connecting the shaft coupling flange to the marine gear with Grade 8, 5/8”-18 x 2-1/4” socket head (allen) cap bolts (I wasn’t able to find 2-1/4” in grade 8 so used 2-1/2” along with grinder modified 1/8” thick, 5/8” head bolt washers under the allen heads). Removes a lot of frustration and makes achieving the correct torque a whole lot easier using a male allen socket instead of struggling with 2 wrenches in a tight part of your engine room.
Good luck!
Kelly Britz, SANDPIPER, NT37-042
Edmonds/Seattle, WA
From: Steve Day via Sentoa <sentoa@lists.sentoa.org>
Sent: Saturday, February 1, 2025 9:23 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.org>
Cc: Steve Day <s.day2905@gmail.com>
Subject: [Sentoa] Cutlass Bearings & shaft sealsHi all, and greetings from the UK.
My 2007 NT37 has now done 2300 hours, when I purchased the boat in 2018 it had done around 1100 hours. As far as I'm aware the cutlass bearings have never been replaced. The boat is in salt water which can be a bit silty on the UK east coast. No undue vibration when going forward, but a bit grumbly in reverse.
Secondly, I have the PSS shaft seal, which I replaced like for like in 2019, whilst the seal does not leak per se, I do get the messy black mist spray that covers the area around the seal.
So, 2 questions:
Have I gone beyond what would be a reasonable length of time / hours to change the bearings? (Does anybody have details of suitable replacements?)
Has anybody tried using lip shaft seals (thinking Lasdrop) instead of PSS and had totally leak free shaft and a nice clean bilge?.
Thanks all
Steve
SINBAD
NT37/192
_______________________________________________
Sentoa mailing list -- sentoa@lists.sentoa.org
To unsubscribe send an email to sentoa-leave@lists.sentoa.org_______________________________________________
Sentoa mailing list -- sentoa@lists.sentoa.org
To unsubscribe send an email to sentoa-leave@lists.sentoa.org