We use Gardner-Bender Duct Seal to keep water from entering around the chain/hawse hole. Purchase at Home Depot or Lowes. Electricians use it to seal conduits and refer to it lovingly as "monkey shit".
Harry Hungate

Bessie NT 32-238

On Sep 16, 2025, at 12:23 PM, Richard Cohen via Sentoa <sentoa@lists.sentoa.org> wrote:

 @font-face { font-family: "Cambria Math"; }
@font-face { font-family: Calibri; }
@font-face { font-family: Verdana; }
@font-face { font-family: Aptos; }
p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0in; font-size: 12pt; font-family: Aptos, sans-serif; }
a:link, span.MsoHyperlink { color: rgb(70, 120, 134); text-decoration: underline; }
span.EmailStyle20 { font-family: Aptos, sans-serif; color: windowtext; }
.MsoChpDefault { font-size: 10pt; }
@page WordSection1 { size: 8.5in 11in; margin: 1in; }
div.WordSection1 { page: WordSection1; }
ol { margin-bottom: 0in; }
ul { margin-bottom: 0in; }On our 37 (NT37-079) the grey water and head sink drains exited above the waterline so unlikely sources.

I replace the entire bow thruster which the factory had installed with 5200, there is a relatively small mounting surface on the thruster leg, but I suspect it is not that. If there is water intrusion there it should be obvious inside the grey metal mount under the motor. If you want/need to take out the bow thruster you need a 17mm cone wrench to hold the bolts behind cables on the lugs. https://www.amazon.com/Bikehand-Bicycle-Install-Remover-Spanner/dp/B089GFQQZT/ref=sr_1_3_sspa?crid=1OD9EX0MS238I&dib=eyJ2IjoiMSJ9.q9PUpcLcHu5-oji8GxuqT6awXifI3ehvILf1rn-EzqC7N64EGBJjbgYwRviDKL_lff0tz26L9Jb_G29I4ab_22OchfNMSCU_VXsbh9ctz3w49Z20WyFRUvqPbWF2qVHD8FBzQHI_YZurqXzIPDXyOSOj33PxDWeJtqJAF9QZzzqM0xMgC0FkosWqOE_waucuc9Q7orOmCYXhpi5VKHe6Wyck7T9MKf0Hmsb9_sQDt3nRHy9Wob06oMKeBpUbUntS9taJukmHp6kldst1gYemtizohl5CD50fQi1QwOH7pQ0.60ictV96fSqUnTkHmqdYIDOJjGPUGpQNopGRaCCG24w&dib_tag=se&keywords=17mm%2Bcone%2Bwrench&qid=1758039408&sprefix=17mm%2Bcone%2B%2Caps%2C136&sr=8-3-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1&psc=1. Do not remove the cables without holding those backing nuts

My assumption is that significant saltwater leakage from the railing and other deck hardware would be hard to produce that much water, if it were fresh water from rain or hose that would make more sense.

I always used modeling clay wrapped around the chain in the hawser under the windless. In rough weather that can let in a ton of salt water. I might try a hose into that hawser and see if that flows into the under bunk area.

Good luck

Richard Cohen
Managing Partner

BOSTONCIO

BostonCIO LLC
(508) 265-7277
RCohen@BostonCIO.com
Facebook | LinkedIn

From: Ben McCafferty via Sentoa <sentoa@lists.sentoa.org>
Sent: Tuesday, September 16, 2025 11:48 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.org>
Cc: tccooper1@comcast.net; Ben McCafferty <bmacpiper@me.com>
Subject: [Sentoa] Re: NT37 Leaks

For both hanging lockers I’d suspect the portholes. The rubber seal in ours has to be perfectly “square” to seal properly. With a little twist in the seal it leaks, and that’s a straight shot down to your locker floors. I know you said walls are dry, but perhaps they dried after the leak and puddling happened? Are the walls carpeted? Have a look at the top of the lockers just below the portholes also—ours are slightly delaminated from other owners (and us) having had a leak there.

V-berth, the obvious thought there would be to start with the penetration of the thruster and go from there. Nothing else comes to mind right away, but perhaps another penetration nearby (grey water thru hull, head sink thru hull, etc.?).

Curious what you find!

On Sep 16, 2025, at 08:34, Tim Cooper via Sentoa <sentoa@lists.sentoa.org> wrote:

After cruising this summer we have more leaks than we were aware of so now it is time to address them. I have gone through the archive and seen mentions but no definite solutions. I will report back once leaks are identified and fixed. I would appreciate any help or guidance from all.

1. Saltwater under V-berth, this has existed since we have owned the boat 2018, I think. I dried it out near the thruster battery and up by the thruster. Just sitting no water, after cruising both places have saltwater. The level is always the same because excess flows to bilge pump. We are normally in freshwater so it hasn’t been a big concern but now it is time to dry it out.
2. Saltwater soaked floor in starboard hanging locker or closet. Using a moisture meter I haven’t found the path for the water. The walls in the closet are dry. This summer is the first time we have seen this.
3. Saltwater soaked floor in port hanging locker or closet. I haven’t done any investigation yet but it doesn’t seem to be as bad as the starboard side. This summer is the first time we have seen this.

Thanks

Tim Cooper 37-059 Time To Play

_______________________________________________
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

Thank you everyone for all the great advice, it is really appreciated.

I started yesterday on the V berth leak focusing on the anchor locker. I omitted what I had done this summer on my original post. After reading the archive, while in Petersburg, I unloaded the anchors and found the bottom of the lockers had a plastic-ish coating. The PO noted having the anchor locker floor rebuilt in 2017. After inspection, I got some plastic tubing and some 4200. I put the 4200 on the tubing and slid it into the drain holes. I had no time to test if it helped or hurt. I gave the 4200 the night to cure and loaded the anchor and we were on our way. I also went around the top rub rail and tightened all the screws.

I dried near the thruster and the battery then ran the thruster in both directions several times with no water intrusion. I unloaded the anchors. Trying to separate the two sides I tried to tape the hole between sides with good heavy-duty tape. It wouldn’t stick to the plastic-ish coating, I tried a couple types but no luck. So, I filled the locker with 6” of water and got a trickle forward of the thruster. I wanted to see if I could separate the drain tube from the floor. I tried using a Phillips screwdriver to plug the tubing in the drain hole but the tubing pushed out the hull and water gushed in forward of the thruster. I repeated pushing out the tubing on the port side with the same result. I finally thought of the foam cone I have for plugging holes in the hull to separate the two sides, it worked ok but the hole isn’t round. The 4200 couldn’t stick to the plastic-ish coating.

I am know focused on removing the plastic-ish coating and finding a tube material that can be epoxied in place. This is likely to take several days, if not longer.

Tim Cooper 37-059 Time To Play

From: Harry Hungate via Sentoa sentoa@lists.sentoa.org
Sent: Tuesday, September 16, 2025 12:11 PM
To: sentoa@lists.sentoa.org
Cc: Harry Hungate wcx7106@gmail.com
Subject: [Sentoa] Re: NT37 Leaks

We use Gardner-Bender Duct Seal to keep water from entering around the chain/hawse hole.  Purchase at Home Depot or Lowes.  Electricians use it to seal conduits and refer to it lovingly as "monkey shit".

Harry Hungate

Bessie NT 32-238

On Sep 16, 2025, at 12:23 PM, Richard Cohen via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org > wrote:



On our 37 (NT37-079) the grey water and head sink drains exited above the waterline so unlikely sources.

I replace the entire bow thruster which the factory had installed with 5200, there is a relatively small mounting surface on the thruster leg, but I suspect it is not that.  If there is water intrusion there it should be obvious inside the grey metal mount under the motor.  If you want/need to take out the bow thruster you need a 17mm cone wrench to hold the bolts behind cables on the lugs. https://www.amazon.com/Bikehand-Bicycle-Install-Remover-Spanner/dp/B089GFQQZT/ref=sr_1_3_sspa?crid=1OD9EX0MS238I&dib=eyJ2IjoiMSJ9.q9PUpcLcHu5-oji8GxuqT6awXifI3ehvILf1rn-EzqC7N64EGBJjbgYwRviDKL_lff0tz26L9Jb_G29I4ab_22OchfNMSCU_VXsbh9ctz3w49Z20WyFRUvqPbWF2qVHD8FBzQHI_YZurqXzIPDXyOSOj33PxDWeJtqJAF9QZzzqM0xMgC0FkosWqOE_waucuc9Q7orOmCYXhpi5VKHe6Wyck7T9MKf0Hmsb9_sQDt3nRHy9Wob06oMKeBpUbUntS9taJukmHp6kldst1gYemtizohl5CD50fQi1QwOH7pQ0.60ictV96fSqUnTkHmqdYIDOJjGPUGpQNopGRaCCG24w&dib_tag=se&keywords=17mm%2Bcone%2Bwrench&qid=1758039408&sprefix=17mm%2Bcone%2B%2Caps%2C136&sr=8-3-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1&psc=1.  Do not remove the cables without holding those backing nuts

My assumption is that significant saltwater leakage from the railing and other deck hardware would be hard to produce that much water, if it were fresh water from rain or hose that would make more sense.

I always used modeling clay wrapped around the chain in the hawser under the windless.  In rough weather that can let in a ton of salt water.  I might try a hose into that hawser and see if that flows into the under bunk area.

Good luck

Richard Cohen
Managing Partner

http://www.bostoncio.com/  BOSTON http://www.bostoncio.com/ CIO

BostonCIO LLC
tel:(508)%20265-7277 (508) 265-7277
mailto:rcohen@bostoncio.com RCohen@BostonCIO.com
https://www.facebook.com/BostonCIO-LLC-209170469076/ Facebook  |  https://www.linkedin.com/company/bostoncio-llc LinkedIn

From: Ben McCafferty via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Sent: Tuesday, September 16, 2025 11:48 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Cc: tccooper1@comcast.net mailto:tccooper1@comcast.net ; Ben McCafferty <bmacpiper@me.com mailto:bmacpiper@me.com >
Subject: [Sentoa] Re: NT37 Leaks

For both hanging lockers I’d suspect the portholes. The rubber seal in ours has to be perfectly “square” to seal properly. With a little twist in the seal it leaks, and that’s a straight shot down to your locker floors. I know you said walls are dry, but perhaps they dried after the leak and puddling happened? Are the walls carpeted? Have a look at the top of the lockers just below the portholes also—ours are slightly delaminated from other owners (and us) having had a leak there.

V-berth, the obvious thought there would be to start with the penetration of the thruster and go from there. Nothing else comes to mind right away, but perhaps another penetration nearby (grey water thru hull, head sink thru hull, etc.?).

Curious what you find!

On Sep 16, 2025, at 08:34, Tim Cooper via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org > wrote:

After cruising this summer we have more leaks than we were aware of so now it is time to address them. I have gone through the archive and seen mentions but no definite solutions. I will report back once leaks are identified and fixed. I would appreciate any help or guidance from all.

1. Saltwater under V-berth, this has existed since we have owned the boat 2018, I think. I dried it out near the thruster battery and up by the thruster. Just sitting no water, after cruising both places have saltwater. The level is always the same because excess flows to bilge pump. We are normally in freshwater so it hasn’t been a big concern but now it is time to dry it out.
2. Saltwater soaked floor in starboard hanging locker or closet. Using a moisture meter I haven’t found the path for the water. The walls in the closet are dry. This summer is the first time we have seen this.
3. Saltwater soaked floor in port hanging locker or closet. I haven’t done any investigation yet but it doesn’t seem to be as bad as the starboard side. This summer is the first time we have seen this.

Thanks

Tim Cooper 37-059 Time To Play

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

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

On 32-251 (2005) there is a single anchor chain drain. It consists of a piece of 1/2” copper tube flaired on the inside. Mine was about 1/2” above the bottom of the locker. To raise the bottom and level it, I used thicken West Epoxy allowing it to self level. After that I also added two layers of DriDek to make sure the chain was not sitting in water.

To diagnose the drain, I used tapered rubber corks (first on inside and then on outside) to see if the water might be traveling around the outside of the copper tube. No leaks.

BTW, I found using my cellphone to inspect areas on the inside very useful.

~Tom

On Sep 17, 2025, at 07:28, Tim Cooper via Sentoa <sentoa@lists.sentoa.org> wrote:

@font-face { font-family: "Cambria Math"; }
@font-face { font-family: Calibri; }
@font-face { font-family: Verdana; }
@font-face { font-family: Aptos; }
@font-face { font-family: Tahoma; }
p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0in; font-size: 12pt; font-family: Aptos, sans-serif; }
a:link, span.MsoHyperlink { color: rgb(70, 120, 134); text-decoration: underline; }
span.EmailStyle22 { font-family: Aptos, sans-serif; color: windowtext; }
.MsoChpDefault { font-size: 10pt; }
@page WordSection1 { size: 8.5in 11in; margin: 1in; }
div.WordSection1 { page: WordSection1; }
ol { margin-bottom: 0in; }
ul { margin-bottom: 0in; }Thank you everyone for all the great advice, it is really appreciated.

I started yesterday on the V berth leak focusing on the anchor locker. I omitted what I had done this summer on my original post. After reading the archive, while in Petersburg, I unloaded the anchors and found the bottom of the lockers had a plastic-ish coating. The PO noted having the anchor locker floor rebuilt in 2017. After inspection, I got some plastic tubing and some 4200. I put the 4200 on the tubing and slid it into the drain holes. I had no time to test if it helped or hurt. I gave the 4200 the night to cure and loaded the anchor and we were on our way. I also went around the top rub rail and tightened all the screws.

I dried near the thruster and the battery then ran the thruster in both directions several times with no water intrusion. I unloaded the anchors. Trying to separate the two sides I tried to tape the hole between sides with good heavy-duty tape. It wouldn’t stick to the plastic-ish coating, I tried a couple types but no luck. So, I filled the locker with 6” of water and got a trickle forward of the thruster. I wanted to see if I could separate the drain tube from the floor. I tried using a Phillips screwdriver to plug the tubing in the drain hole but the tubing pushed out the hull and water gushed in forward of the thruster. I repeated pushing out the tubing on the port side with the same result. I finally thought of the foam cone I have for plugging holes in the hull to separate the two sides, it worked ok but the hole isn’t round. The 4200 couldn’t stick to the plastic-ish coating.

I am know focused on removing the plastic-ish coating and finding a tube material that can be epoxied in place. This is likely to take several days, if not longer.

Tim Cooper 37-059 Time To Play

From: Harry Hungate via Sentoa <sentoa@lists.sentoa.org>
Sent: Tuesday, September 16, 2025 12:11 PM
To: sentoa@lists.sentoa.org
Cc: Harry Hungate <wcx7106@gmail.com>
Subject: [Sentoa] Re: NT37 Leaks

We use Gardner-Bender Duct Seal to keep water from entering around the chain/hawse hole. Purchase at Home Depot or Lowes. Electricians use it to seal conduits and refer to it lovingly as "monkey shit".

Harry Hungate

Bessie NT 32-238

On Sep 16, 2025, at 12:23 PM, Richard Cohen via Sentoa <sentoa@lists.sentoa.org> wrote:



On our 37 (NT37-079) the grey water and head sink drains exited above the waterline so unlikely sources.

I replace the entire bow thruster which the factory had installed with 5200, there is a relatively small mounting surface on the thruster leg, but I suspect it is not that. If there is water intrusion there it should be obvious inside the grey metal mount under the motor. If you want/need to take out the bow thruster you need a 17mm cone wrench to hold the bolts behind cables on the lugs. https://www.amazon.com/Bikehand-Bicycle-Install-Remover-Spanner/dp/B089GFQQZT/ref=sr_1_3_sspa?crid=1OD9EX0MS238I&dib=eyJ2IjoiMSJ9.q9PUpcLcHu5-oji8GxuqT6awXifI3ehvILf1rn-EzqC7N64EGBJjbgYwRviDKL_lff0tz26L9Jb_G29I4ab_22OchfNMSCU_VXsbh9ctz3w49Z20WyFRUvqPbWF2qVHD8FBzQHI_YZurqXzIPDXyOSOj33PxDWeJtqJAF9QZzzqM0xMgC0FkosWqOE_waucuc9Q7orOmCYXhpi5VKHe6Wyck7T9MKf0Hmsb9_sQDt3nRHy9Wob06oMKeBpUbUntS9taJukmHp6kldst1gYemtizohl5CD50fQi1QwOH7pQ0.60ictV96fSqUnTkHmqdYIDOJjGPUGpQNopGRaCCG24w&dib_tag=se&keywords=17mm%2Bcone%2Bwrench&qid=1758039408&sprefix=17mm%2Bcone%2B%2Caps%2C136&sr=8-3-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1&psc=1. Do not remove the cables without holding those backing nuts

My assumption is that significant saltwater leakage from the railing and other deck hardware would be hard to produce that much water, if it were fresh water from rain or hose that would make more sense.

I always used modeling clay wrapped around the chain in the hawser under the windless. In rough weather that can let in a ton of salt water. I might try a hose into that hawser and see if that flows into the under bunk area.

Good luck

Richard Cohen
Managing Partner

BOSTONCIO

BostonCIO LLC
(508) 265-7277
RCohen@BostonCIO.com
Facebook | LinkedIn

From: Ben McCafferty via Sentoa <sentoa@lists.sentoa.org>
Sent: Tuesday, September 16, 2025 11:48 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.org>
Cc: tccooper1@comcast.net; Ben McCafferty <bmacpiper@me.com>
Subject: [Sentoa] Re: NT37 Leaks

For both hanging lockers I’d suspect the portholes. The rubber seal in ours has to be perfectly “square” to seal properly. With a little twist in the seal it leaks, and that’s a straight shot down to your locker floors. I know you said walls are dry, but perhaps they dried after the leak and puddling happened? Are the walls carpeted? Have a look at the top of the lockers just below the portholes also—ours are slightly delaminated from other owners (and us) having had a leak there.

V-berth, the obvious thought there would be to start with the penetration of the thruster and go from there. Nothing else comes to mind right away, but perhaps another penetration nearby (grey water thru hull, head sink thru hull, etc.?).

Curious what you find!

On Sep 16, 2025, at 08:34, Tim Cooper via Sentoa <sentoa@lists.sentoa.org> wrote:

After cruising this summer we have more leaks than we were aware of so now it is time to address them. I have gone through the archive and seen mentions but no definite solutions. I will report back once leaks are identified and fixed. I would appreciate any help or guidance from all.

1. Saltwater under V-berth, this has existed since we have owned the boat 2018, I think. I dried it out near the thruster battery and up by the thruster. Just sitting no water, after cruising both places have saltwater. The level is always the same because excess flows to bilge pump. We are normally in freshwater so it hasn’t been a big concern but now it is time to dry it out.
2. Saltwater soaked floor in starboard hanging locker or closet. Using a moisture meter I haven’t found the path for the water. The walls in the closet are dry. This summer is the first time we have seen this.
3. Saltwater soaked floor in port hanging locker or closet. I haven’t done any investigation yet but it doesn’t seem to be as bad as the starboard side. This summer is the first time we have seen this.

Thanks

Tim Cooper 37-059 Time To Play

_______________________________________________
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

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

All,

To start, actions from suggestions.

I sprayed with pressure and soaked/flooded the vertical bow strips without any water intrusion.

I purchased some of the duct seal to use in the future. I used it to separate the locker sides and it worked great.

The PO had grids of starboard made to fit the bottom of each locker side to keep the rode out of remaining water.

I traded emails with Dave Allen at Nordic Tug. He explained how the factory does it today. He was very helpful.

Our anchor locker appears to be all custom. When it was split in two there was a drain put in both sides, smaller than what NT does today. Then in 2017 the floor was rebuilt. After removing the clam shells on the hull, it exposed football shaped holes larger than the drain holes in the locker. With a pick I was able to feel the inside of the hull and then the anchor locker structure, I assume, since I couldn’t see in there. I didn’t find anything that I thought would keep water out of the bilge. So, I cleaned around the holes down to fiberglass and drilled the holes out a little to get rid of any of the plastic-ish coating that was put on before. I found filament wound epoxy tubes at Tap Plastics (od 0.37”, id 0.296) that I cut long. Then filled all around the tube with Sikaflex 291, replaced the clamshells, sealed around the tube in the locker without moving the tubes. I had to rework some of the sealant in one locker but all is dry in the bilge now. I filled both sides of the locker with 6-8 inches of water, several times, and ran the hose into the clamshells for minutes.

Next week I will start trying to find the leak causing the starboard side hanging locker floor to be wet.

Tim Cooper 37-059 Time To Play

From: Tom Patterson via Sentoa sentoa@lists.sentoa.org
Sent: Wednesday, September 17, 2025 8:39 AM
To: South East Nordic Tugs Owners' Association (SENTOA) sentoa@lists.sentoa.org
Cc: Tim Cooper tccooper1@comcast.net; Tom Patterson tpatterson888@gmail.com
Subject: [Sentoa] Re: NT37 Leaks

On 32-251 (2005) there is a single anchor chain drain. It consists of a piece of 1/2” copper tube flaired on the inside. Mine was about 1/2” above the bottom of the locker. To raise the bottom and level it, I used thicken West Epoxy allowing it to self level. After that I also added two layers of DriDek to make sure the chain was not sitting in water.

To diagnose the drain, I used tapered rubber corks (first on inside and then on outside) to see if the water might be traveling around the outside of the copper tube.  No leaks.

BTW, I found using my cellphone to inspect areas on the inside very useful.

~Tom

On Sep 17, 2025, at 07:28, Tim Cooper via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org > wrote:



Thank you everyone for all the great advice, it is really appreciated.

I started yesterday on the V berth leak focusing on the anchor locker. I omitted what I had done this summer on my original post. After reading the archive, while in Petersburg, I unloaded the anchors and found the bottom of the lockers had a plastic-ish coating. The PO noted having the anchor locker floor rebuilt in 2017. After inspection, I got some plastic tubing and some 4200. I put the 4200 on the tubing and slid it into the drain holes. I had no time to test if it helped or hurt. I gave the 4200 the night to cure and loaded the anchor and we were on our way. I also went around the top rub rail and tightened all the screws.

I dried near the thruster and the battery then ran the thruster in both directions several times with no water intrusion. I unloaded the anchors. Trying to separate the two sides I tried to tape the hole between sides with good heavy-duty tape. It wouldn’t stick to the plastic-ish coating, I tried a couple types but no luck. So, I filled the locker with 6” of water and got a trickle forward of the thruster. I wanted to see if I could separate the drain tube from the floor. I tried using a Phillips screwdriver to plug the tubing in the drain hole but the tubing pushed out the hull and water gushed in forward of the thruster. I repeated pushing out the tubing on the port side with the same result. I finally thought of the foam cone I have for plugging holes in the hull to separate the two sides, it worked ok but the hole isn’t round. The 4200 couldn’t stick to the plastic-ish coating.

I am know focused on removing the plastic-ish coating and finding a tube material that can be epoxied in place. This is likely to take several days, if not longer.

Tim Cooper 37-059 Time To Play

From: Harry Hungate via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Sent: Tuesday, September 16, 2025 12:11 PM
To: sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org
Cc: Harry Hungate <wcx7106@gmail.com mailto:wcx7106@gmail.com >
Subject: [Sentoa] Re: NT37 Leaks

We use Gardner-Bender Duct Seal to keep water from entering around the chain/hawse hole.  Purchase at Home Depot or Lowes.  Electricians use it to seal conduits and refer to it lovingly as "monkey shit".

Harry Hungate

Bessie NT 32-238

On Sep 16, 2025, at 12:23 PM, Richard Cohen via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org > wrote:



On our 37 (NT37-079) the grey water and head sink drains exited above the waterline so unlikely sources.

I replace the entire bow thruster which the factory had installed with 5200, there is a relatively small mounting surface on the thruster leg, but I suspect it is not that.  If there is water intrusion there it should be obvious inside the grey metal mount under the motor.  If you want/need to take out the bow thruster you need a 17mm cone wrench to hold the bolts behind cables on the lugs. https://www.amazon.com/Bikehand-Bicycle-Install-Remover-Spanner/dp/B089GFQQZT/ref=sr_1_3_sspa?crid=1OD9EX0MS238I&dib=eyJ2IjoiMSJ9.q9PUpcLcHu5-oji8GxuqT6awXifI3ehvILf1rn-EzqC7N64EGBJjbgYwRviDKL_lff0tz26L9Jb_G29I4ab_22OchfNMSCU_VXsbh9ctz3w49Z20WyFRUvqPbWF2qVHD8FBzQHI_YZurqXzIPDXyOSOj33PxDWeJtqJAF9QZzzqM0xMgC0FkosWqOE_waucuc9Q7orOmCYXhpi5VKHe6Wyck7T9MKf0Hmsb9_sQDt3nRHy9Wob06oMKeBpUbUntS9taJukmHp6kldst1gYemtizohl5CD50fQi1QwOH7pQ0.60ictV96fSqUnTkHmqdYIDOJjGPUGpQNopGRaCCG24w&dib_tag=se&keywords=17mm%2Bcone%2Bwrench&qid=1758039408&sprefix=17mm%2Bcone%2B%2Caps%2C136&sr=8-3-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1&psc=1.  Do not remove the cables without holding those backing nuts

My assumption is that significant saltwater leakage from the railing and other deck hardware would be hard to produce that much water, if it were fresh water from rain or hose that would make more sense.

I always used modeling clay wrapped around the chain in the hawser under the windless.  In rough weather that can let in a ton of salt water.  I might try a hose into that hawser and see if that flows into the under bunk area.

Good luck

Richard Cohen
Managing Partner

http://www.bostoncio.com/  BOSTON http://www.bostoncio.com/ CIO

BostonCIO LLC
tel:(508)%20265-7277 (508) 265-7277
mailto:rcohen@bostoncio.com RCohen@BostonCIO.com
https://www.facebook.com/BostonCIO-LLC-209170469076/ Facebook  |  https://www.linkedin.com/company/bostoncio-llc LinkedIn

From: Ben McCafferty via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Sent: Tuesday, September 16, 2025 11:48 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Cc: tccooper1@comcast.net mailto:tccooper1@comcast.net ; Ben McCafferty <bmacpiper@me.com mailto:bmacpiper@me.com >
Subject: [Sentoa] Re: NT37 Leaks

For both hanging lockers I’d suspect the portholes. The rubber seal in ours has to be perfectly “square” to seal properly. With a little twist in the seal it leaks, and that’s a straight shot down to your locker floors. I know you said walls are dry, but perhaps they dried after the leak and puddling happened? Are the walls carpeted? Have a look at the top of the lockers just below the portholes also—ours are slightly delaminated from other owners (and us) having had a leak there.

V-berth, the obvious thought there would be to start with the penetration of the thruster and go from there. Nothing else comes to mind right away, but perhaps another penetration nearby (grey water thru hull, head sink thru hull, etc.?).

Curious what you find!

On Sep 16, 2025, at 08:34, Tim Cooper via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org > wrote:

After cruising this summer we have more leaks than we were aware of so now it is time to address them. I have gone through the archive and seen mentions but no definite solutions. I will report back once leaks are identified and fixed. I would appreciate any help or guidance from all.

1. Saltwater under V-berth, this has existed since we have owned the boat 2018, I think. I dried it out near the thruster battery and up by the thruster. Just sitting no water, after cruising both places have saltwater. The level is always the same because excess flows to bilge pump. We are normally in freshwater so it hasn’t been a big concern but now it is time to dry it out.
2. Saltwater soaked floor in starboard hanging locker or closet. Using a moisture meter I haven’t found the path for the water. The walls in the closet are dry. This summer is the first time we have seen this.
3. Saltwater soaked floor in port hanging locker or closet. I haven’t done any investigation yet but it doesn’t seem to be as bad as the starboard side. This summer is the first time we have seen this.

Thanks

Tim Cooper 37-059 Time To Play

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

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

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

Update Starboard hanging locker leak:

I started by pulling the carpet back inside the cabinets to get access to the station bases and the upper rub rail forward of the hanging locker. I also removed the ceiling piece from the starboard bow. This is the first time I have removed a ceiling panel. In addition to the teak trim screws and the exposed screws there are screws along the seam that are hidden by the foam and vinyl.

Using high pressure and flooding several times I was unable to find any leaks around the stations or the rub rail. I moved to the port light and on my first check I saw a wet spot and then a drip. There was no evidence of water on the inside near the port. I did remove inside screws looking for wetness but just some rusty screws. In fact, two screws broke as I reinserted them with very little force.

Before removal I wanted to get silicone and screws on order. I was unable to find the same screw in square drive, 316 stainless. They were available in 304 stainless but with broken screws I didn’t want to push my luck, so I decided to deal with Phillips. I will replace all 96 screws.

After removing all the screws, with a sharpened putty knife I removed the trim ring and picked out the seal around the port. It was much easier than I expected. The port was out in less than 15 minutes; the time-consuming part was removing the silicone from the port. The original black silicone came off easy but the clear silicone that had been spread all over the outside of the port was very difficult to remove. I was surprised at how well this 23-year-old port light looked once it was cleaned up.

I started on the port side following the same process as the starboard side but didn’t remove the ceiling. After lots of spraying I was unable to find any leaks or wetness near the stations, rub rail or hanging locker. I removed a lower inside screw from the port and it was wet. I removed the port in same manner as above.

I reinstalled the two ports and re-bedded them. I tightened the inside screws tight and left the outside screws loose so as not to squeeze the silicone out. I had one inside screw and eight outside screws stripped. I used polyurethane glue and toothpicks to tighten up the screws. On the next four I will fix the holes before reinserting the ports

While testing the rub rail I noted that there are backer-boards glassed in along the edge but there are gaps without. Near the forward cleats is one area without. On the starboard side there were dimples where screws were just poking through or almost poking through. On the port side in the same spot a screw was through the hull by 0.5-0.75 inches. I would like to put in a backer with thickened epoxy, but I haven’t checked clearances yet. I am sure there was a reason it was done this way.

Tim Cooper 37-059 Time To Play

From: Tim Cooper via Sentoa sentoa@lists.sentoa.org
Sent: Saturday, September 27, 2025 6:22 AM
To: 'South East Nordic Tugs Owners' Association (SENTOA)' sentoa@lists.sentoa.org
Cc: Tim Cooper tccooper1@comcast.net
Subject: [Sentoa] Re: NT37 Leaks

All,

To start, actions from suggestions.

I sprayed with pressure and soaked/flooded the vertical bow strips without any water intrusion.

I purchased some of the duct seal to use in the future. I used it to separate the locker sides and it worked great.

The PO had grids of starboard made to fit the bottom of each locker side to keep the rode out of remaining water.

I traded emails with Dave Allen at Nordic Tug. He explained how the factory does it today. He was very helpful.

Our anchor locker appears to be all custom. When it was split in two there was a drain put in both sides, smaller than what NT does today. Then in 2017 the floor was rebuilt. After removing the clam shells on the hull, it exposed football shaped holes larger than the drain holes in the locker. With a pick I was able to feel the inside of the hull and then the anchor locker structure, I assume, since I couldn’t see in there. I didn’t find anything that I thought would keep water out of the bilge. So, I cleaned around the holes down to fiberglass and drilled the holes out a little to get rid of any of the plastic-ish coating that was put on before. I found filament wound epoxy tubes at Tap Plastics (od 0.37”, id 0.296) that I cut long. Then filled all around the tube with Sikaflex 291, replaced the clamshells, sealed around the tube in the locker without moving the tubes. I had to rework some of the sealant in one locker but all is dry in the bilge now. I filled both sides of the locker with 6-8 inches of water, several times, and ran the hose into the clamshells for minutes.

Next week I will start trying to find the leak causing the starboard side hanging locker floor to be wet.

Tim Cooper 37-059 Time To Play

From: Tom Patterson via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Sent: Wednesday, September 17, 2025 8:39 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Cc: Tim Cooper <tccooper1@comcast.net mailto:tccooper1@comcast.net >; Tom Patterson <tpatterson888@gmail.com mailto:tpatterson888@gmail.com >
Subject: [Sentoa] Re: NT37 Leaks

On 32-251 (2005) there is a single anchor chain drain. It consists of a piece of 1/2” copper tube flaired on the inside. Mine was about 1/2” above the bottom of the locker. To raise the bottom and level it, I used thicken West Epoxy allowing it to self level. After that I also added two layers of DriDek to make sure the chain was not sitting in water.

To diagnose the drain, I used tapered rubber corks (first on inside and then on outside) to see if the water might be traveling around the outside of the copper tube.  No leaks.

BTW, I found using my cellphone to inspect areas on the inside very useful.

~Tom

On Sep 17, 2025, at 07:28, Tim Cooper via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org > wrote:



Thank you everyone for all the great advice, it is really appreciated.

I started yesterday on the V berth leak focusing on the anchor locker. I omitted what I had done this summer on my original post. After reading the archive, while in Petersburg, I unloaded the anchors and found the bottom of the lockers had a plastic-ish coating. The PO noted having the anchor locker floor rebuilt in 2017. After inspection, I got some plastic tubing and some 4200. I put the 4200 on the tubing and slid it into the drain holes. I had no time to test if it helped or hurt. I gave the 4200 the night to cure and loaded the anchor and we were on our way. I also went around the top rub rail and tightened all the screws.

I dried near the thruster and the battery then ran the thruster in both directions several times with no water intrusion. I unloaded the anchors. Trying to separate the two sides I tried to tape the hole between sides with good heavy-duty tape. It wouldn’t stick to the plastic-ish coating, I tried a couple types but no luck. So, I filled the locker with 6” of water and got a trickle forward of the thruster. I wanted to see if I could separate the drain tube from the floor. I tried using a Phillips screwdriver to plug the tubing in the drain hole but the tubing pushed out the hull and water gushed in forward of the thruster. I repeated pushing out the tubing on the port side with the same result. I finally thought of the foam cone I have for plugging holes in the hull to separate the two sides, it worked ok but the hole isn’t round. The 4200 couldn’t stick to the plastic-ish coating.

I am know focused on removing the plastic-ish coating and finding a tube material that can be epoxied in place. This is likely to take several days, if not longer.

Tim Cooper 37-059 Time To Play

From: Harry Hungate via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Sent: Tuesday, September 16, 2025 12:11 PM
To: sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org
Cc: Harry Hungate <wcx7106@gmail.com mailto:wcx7106@gmail.com >
Subject: [Sentoa] Re: NT37 Leaks

We use Gardner-Bender Duct Seal to keep water from entering around the chain/hawse hole.  Purchase at Home Depot or Lowes.  Electricians use it to seal conduits and refer to it lovingly as "monkey shit".

Harry Hungate

Bessie NT 32-238

On Sep 16, 2025, at 12:23 PM, Richard Cohen via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org > wrote:



On our 37 (NT37-079) the grey water and head sink drains exited above the waterline so unlikely sources.

I replace the entire bow thruster which the factory had installed with 5200, there is a relatively small mounting surface on the thruster leg, but I suspect it is not that.  If there is water intrusion there it should be obvious inside the grey metal mount under the motor.  If you want/need to take out the bow thruster you need a 17mm cone wrench to hold the bolts behind cables on the lugs. https://www.amazon.com/Bikehand-Bicycle-Install-Remover-Spanner/dp/B089GFQQZT/ref=sr_1_3_sspa?crid=1OD9EX0MS238I&dib=eyJ2IjoiMSJ9.q9PUpcLcHu5-oji8GxuqT6awXifI3ehvILf1rn-EzqC7N64EGBJjbgYwRviDKL_lff0tz26L9Jb_G29I4ab_22OchfNMSCU_VXsbh9ctz3w49Z20WyFRUvqPbWF2qVHD8FBzQHI_YZurqXzIPDXyOSOj33PxDWeJtqJAF9QZzzqM0xMgC0FkosWqOE_waucuc9Q7orOmCYXhpi5VKHe6Wyck7T9MKf0Hmsb9_sQDt3nRHy9Wob06oMKeBpUbUntS9taJukmHp6kldst1gYemtizohl5CD50fQi1QwOH7pQ0.60ictV96fSqUnTkHmqdYIDOJjGPUGpQNopGRaCCG24w&dib_tag=se&keywords=17mm%2Bcone%2Bwrench&qid=1758039408&sprefix=17mm%2Bcone%2B%2Caps%2C136&sr=8-3-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1&psc=1.  Do not remove the cables without holding those backing nuts

My assumption is that significant saltwater leakage from the railing and other deck hardware would be hard to produce that much water, if it were fresh water from rain or hose that would make more sense.

I always used modeling clay wrapped around the chain in the hawser under the windless.  In rough weather that can let in a ton of salt water.  I might try a hose into that hawser and see if that flows into the under bunk area.

Good luck

Richard Cohen
Managing Partner

http://www.bostoncio.com/  BOSTON http://www.bostoncio.com/ CIO

BostonCIO LLC
tel:(508)%20265-7277 (508) 265-7277
mailto:rcohen@bostoncio.com RCohen@BostonCIO.com
https://www.facebook.com/BostonCIO-LLC-209170469076/ Facebook  |  https://www.linkedin.com/company/bostoncio-llc LinkedIn

From: Ben McCafferty via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Sent: Tuesday, September 16, 2025 11:48 AM
To: South East Nordic Tugs Owners' Association (SENTOA) <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Cc: tccooper1@comcast.net mailto:tccooper1@comcast.net ; Ben McCafferty <bmacpiper@me.com mailto:bmacpiper@me.com >
Subject: [Sentoa] Re: NT37 Leaks

For both hanging lockers I’d suspect the portholes. The rubber seal in ours has to be perfectly “square” to seal properly. With a little twist in the seal it leaks, and that’s a straight shot down to your locker floors. I know you said walls are dry, but perhaps they dried after the leak and puddling happened? Are the walls carpeted? Have a look at the top of the lockers just below the portholes also—ours are slightly delaminated from other owners (and us) having had a leak there.

V-berth, the obvious thought there would be to start with the penetration of the thruster and go from there. Nothing else comes to mind right away, but perhaps another penetration nearby (grey water thru hull, head sink thru hull, etc.?).

Curious what you find!

On Sep 16, 2025, at 08:34, Tim Cooper via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org > wrote:

After cruising this summer we have more leaks than we were aware of so now it is time to address them. I have gone through the archive and seen mentions but no definite solutions. I will report back once leaks are identified and fixed. I would appreciate any help or guidance from all.

1. Saltwater under V-berth, this has existed since we have owned the boat 2018, I think. I dried it out near the thruster battery and up by the thruster. Just sitting no water, after cruising both places have saltwater. The level is always the same because excess flows to bilge pump. We are normally in freshwater so it hasn’t been a big concern but now it is time to dry it out.
2. Saltwater soaked floor in starboard hanging locker or closet. Using a moisture meter I haven’t found the path for the water. The walls in the closet are dry. This summer is the first time we have seen this.
3. Saltwater soaked floor in port hanging locker or closet. I haven’t done any investigation yet but it doesn’t seem to be as bad as the starboard side. This summer is the first time we have seen this.

Thanks

Tim Cooper 37-059 Time To Play

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

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

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

Evan,

Thanks for the suggestions. I tend to agree with you about silicone, but it is what Beckson recommends and what NT used originally. I was able to get all the residue off with scraping then sanded the gelcoat edge and the epoxy coated foam core with 60 grit followed by clean up with acetone.

Tim

From: Evan Effa via Sentoa sentoa@lists.sentoa.org
Sent: Wednesday, October 8, 2025 7:26 AM
To: Association South East Nordic Tugs Owners' (SENTOA) sentoa@lists.sentoa.org
Cc: Tim Cooper tccooper1@comcast.net; Evan Effa eheffa@gmail.com
Subject: [Sentoa] Re: NT37 Leaks

HI,

Sounds like an ordeal!

For what it's worth, silicone sealant should be avoided at all costs... It does not seal out water very well and inhibits other sealants from producing a good seal or bond.

I would suggest removing all the residual silicone with brake cleaning fluid and using Sikaflex or similar sealants for a much better repair.

Good luck.

-Evan

TUGAWAY

NT 37-148

Victoria, BC

On Oct 8, 2025, at 07:13, Tim Cooper via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org > wrote:

Update Starboard hanging locker leak:

I started by pulling the carpet back inside the cabinets to get access to the station bases and the upper rub rail forward of the hanging locker. I also removed the ceiling piece from the starboard bow. This is the first time I have removed a ceiling panel. In addition to the teak trim screws and the exposed screws there are screws along the seam that are hidden by the foam and vinyl.

Using high pressure and flooding several times I was unable to find any leaks around the stations or the rub rail. I moved to the port light and on my first check I saw a wet spot and then a drip. There was no evidence of water on the inside near the port. I did remove inside screws looking for wetness but just some rusty screws. In fact, two screws broke as I reinserted them with very little force.

Before removal I wanted to get silicone and screws on order. I was unable to find the same screw in square drive, 316 stainless. They were available in 304 stainless but with broken screws I didn’t want to push my luck, so I decided to deal with Phillips. I will replace all 96 screws.

After removing all the screws, with a sharpened putty knife I removed the trim ring and picked out the seal around the port. It was much easier than I expected. The port was out in less than 15 minutes; the time-consuming part was removing the silicone from the port. The original black silicone came off easy but the clear silicone that had been spread all over the outside of the port was very difficult to remove. I was surprised at how well this 23-year-old port light looked once it was cleaned up.

I started on the port side following the same process as the starboard side but didn’t remove the ceiling. After lots of spraying I was unable to find any leaks or wetness near the stations, rub rail or hanging locker. I removed a lower inside screw from the port and it was wet. I removed the port in same manner as above.

I reinstalled the two ports and re-bedded them. I tightened the inside screws tight and left the outside screws loose so as not to squeeze the silicone out. I had one inside screw and eight outside screws stripped. I used polyurethane glue and toothpicks to tighten up the screws. On the next four I will fix the holes before reinserting the ports

While testing the rub rail I noted that there are backer-boards glassed in along the edge but there are gaps without. Near the forward cleats is one area without. On the starboard side there were dimples where screws were just poking through or almost poking through. On the port side in the same spot a screw was through the hull by 0.5-0.75 inches. I would like to put in a backer with thickened epoxy, but I haven’t checked clearances yet. I am sure there was a reason it was done this way.

Tim Cooper 37-059 Time To Play

From: Tim Cooper via Sentoa <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Sent: Saturday, September 27, 2025 6:22 AM
To: 'South East Nordic Tugs Owners' Association (SENTOA)' <sentoa@lists.sentoa.org mailto:sentoa@lists.sentoa.org >
Cc: Tim Cooper <tccooper1@comcast.net mailto:tccooper1@comcast.net >
Subject: [Sentoa] Re: NT37 Leaks

All,

To start, actions from suggestions.

I sprayed with pressure and soaked/flooded the vertical bow strips without any water intrusion.

I purchased some of the duct seal to use in the future. I used it to separate the locker sides and it worked great.

The PO had grids of starboard made to fit the bottom of each locker side to keep the rode out of remaining water.

I traded emails with Dave Allen at Nordic Tug. He explained how the factory does it today. He was very helpful.

Our anchor locker appears to be all custom. When it was split in two there was a drain put in both sides, smaller than what NT does today. Then in 2017 the floor was rebuilt. After removing the clam shells on the hull, it exposed football shaped holes larger than the drain holes in the locker. With a pick I was able to feel the inside of the hull and then the anchor locker structure, I assume, since I couldn’t see in there. I didn’t find anything that I thought would keep water out of the bilge. So, I cleaned around the holes down to fiberglass and drilled the holes out a little to get rid of any of the plastic-ish coating that was put on before. I found filament wound epoxy tubes at Tap Plastics (od 0.37”, id 0.296) that I cut long. Then filled all around the tube with Sikaflex 291, replaced the clamshells, sealed around the tube in the locker without moving the tubes. I had to rework some of the sealant in one locker but all is dry in the bilge now. I filled both sides of the locker with 6-8 inches of water, several times, and ran the hose into the clamshells for minutes.

Next week I will start trying to find the leak causing the starboard side hanging locker floor to be wet.

Tim Cooper 37-059 Time To Play

From: Tom Patterson via Sentoa < mailto:sentoa@lists.sentoa.org sentoa@lists.sentoa.org>
Sent: Wednesday, September 17, 2025 8:39 AM
To: South East Nordic Tugs Owners' Association (SENTOA) < mailto:sentoa@lists.sentoa.org sentoa@lists.sentoa.org>
Cc: Tim Cooper < mailto:tccooper1@comcast.net tccooper1@comcast.net>; Tom Patterson < mailto:tpatterson888@gmail.com tpatterson888@gmail.com>
Subject: [Sentoa] Re: NT37 Leaks

On 32-251 (2005) there is a single anchor chain drain. It consists of a piece of 1/2” copper tube flaired on the inside. Mine was about 1/2” above the bottom of the locker. To raise the bottom and level it, I used thicken West Epoxy allowing it to self level. After that I also added two layers of DriDek to make sure the chain was not sitting in water.

To diagnose the drain, I used tapered rubber corks (first on inside and then on outside) to see if the water might be traveling around the outside of the copper tube.  No leaks.

BTW, I found using my cellphone to inspect areas on the inside very useful.

~Tom

On Sep 17, 2025, at 07:28, Tim Cooper via Sentoa < mailto:sentoa@lists.sentoa.org sentoa@lists.sentoa.org> wrote:



Thank you everyone for all the great advice, it is really appreciated.

I started yesterday on the V berth leak focusing on the anchor locker. I omitted what I had done this summer on my original post. After reading the archive, while in Petersburg, I unloaded the anchors and found the bottom of the lockers had a plastic-ish coating. The PO noted having the anchor locker floor rebuilt in 2017. After inspection, I got some plastic tubing and some 4200. I put the 4200 on the tubing and slid it into the drain holes. I had no time to test if it helped or hurt. I gave the 4200 the night to cure and loaded the anchor and we were on our way. I also went around the top rub rail and tightened all the screws.

I dried near the thruster and the battery then ran the thruster in both directions several times with no water intrusion. I unloaded the anchors. Trying to separate the two sides I tried to tape the hole between sides with good heavy-duty tape. It wouldn’t stick to the plastic-ish coating, I tried a couple types but no luck. So, I filled the locker with 6” of water and got a trickle forward of the thruster. I wanted to see if I could separate the drain tube from the floor. I tried using a Phillips screwdriver to plug the tubing in the drain hole but the tubing pushed out the hull and water gushed in forward of the thruster. I repeated pushing out the tubing on the port side with the same result. I finally thought of the foam cone I have for plugging holes in the hull to separate the two sides, it worked ok but the hole isn’t round. The 4200 couldn’t stick to the plastic-ish coating.

I am know focused on removing the plastic-ish coating and finding a tube material that can be epoxied in place. This is likely to take several days, if not longer.

Tim Cooper 37-059 Time To Play

From: Harry Hungate via Sentoa < mailto:sentoa@lists.sentoa.org sentoa@lists.sentoa.org>
Sent: Tuesday, September 16, 2025 12:11 PM
To:  mailto:sentoa@lists.sentoa.org sentoa@lists.sentoa.org
Cc: Harry Hungate < mailto:wcx7106@gmail.com wcx7106@gmail.com>
Subject: [Sentoa] Re: NT37 Leaks

We use Gardner-Bender Duct Seal to keep water from entering around the chain/hawse hole.  Purchase at Home Depot or Lowes.  Electricians use it to seal conduits and refer to it lovingly as "monkey shit".

Harry Hungate

Bessie NT 32-238

On Sep 16, 2025, at 12:23 PM, Richard Cohen via Sentoa < mailto:sentoa@lists.sentoa.org sentoa@lists.sentoa.org> wrote:



On our 37 (NT37-079) the grey water and head sink drains exited above the waterline so unlikely sources.

I replace the entire bow thruster which the factory had installed with 5200, there is a relatively small mounting surface on the thruster leg, but I suspect it is not that.  If there is water intrusion there it should be obvious inside the grey metal mount under the motor.  If you want/need to take out the bow thruster you need a 17mm cone wrench to hold the bolts behind cables on the lugs. https://www.amazon.com/Bikehand-Bicycle-Install-Remover-Spanner/dp/B089GFQQZT/ref=sr_1_3_sspa?crid=1OD9EX0MS238I&dib=eyJ2IjoiMSJ9.q9PUpcLcHu5-oji8GxuqT6awXifI3ehvILf1rn-EzqC7N64EGBJjbgYwRviDKL_lff0tz26L9Jb_G29I4ab_22OchfNMSCU_VXsbh9ctz3w49Z20WyFRUvqPbWF2qVHD8FBzQHI_YZurqXzIPDXyOSOj33PxDWeJtqJAF9QZzzqM0xMgC0FkosWqOE_waucuc9Q7orOmCYXhpi5VKHe6Wyck7T9MKf0Hmsb9_sQDt3nRHy9Wob06oMKeBpUbUntS9taJukmHp6kldst1gYemtizohl5CD50fQi1QwOH7pQ0.60ictV96fSqUnTkHmqdYIDOJjGPUGpQNopGRaCCG24w&dib_tag=se&keywords=17mm%2Bcone%2Bwrench&qid=1758039408&sprefix=17mm%2Bcone%2B%2Caps%2C136&sr=8-3-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1&psc=1.  Do not remove the cables without holding those backing nuts

My assumption is that significant saltwater leakage from the railing and other deck hardware would be hard to produce that much water, if it were fresh water from rain or hose that would make more sense.

I always used modeling clay wrapped around the chain in the hawser under the windless.  In rough weather that can let in a ton of salt water.  I might try a hose into that hawser and see if that flows into the under bunk area.

Good luck

Richard Cohen
Managing Partner

http://www.bostoncio.com/  BOSTON http://www.bostoncio.com/ CIO

BostonCIO LLC
tel:(508)%20265-7277 (508) 265-7277
mailto:rcohen@bostoncio.com RCohen@BostonCIO.com
https://www.facebook.com/BostonCIO-LLC-209170469076/ Facebook  |  https://www.linkedin.com/company/bostoncio-llc LinkedIn

From: Ben McCafferty via Sentoa < mailto:sentoa@lists.sentoa.org sentoa@lists.sentoa.org>
Sent: Tuesday, September 16, 2025 11:48 AM
To: South East Nordic Tugs Owners' Association (SENTOA) < mailto:sentoa@lists.sentoa.org sentoa@lists.sentoa.org>
Cc:  mailto:tccooper1@comcast.net tccooper1@comcast.net; Ben McCafferty < mailto:bmacpiper@me.com bmacpiper@me.com>
Subject: [Sentoa] Re: NT37 Leaks

For both hanging lockers I’d suspect the portholes. The rubber seal in ours has to be perfectly “square” to seal properly. With a little twist in the seal it leaks, and that’s a straight shot down to your locker floors. I know you said walls are dry, but perhaps they dried after the leak and puddling happened? Are the walls carpeted? Have a look at the top of the lockers just below the portholes also—ours are slightly delaminated from other owners (and us) having had a leak there.

V-berth, the obvious thought there would be to start with the penetration of the thruster and go from there. Nothing else comes to mind right away, but perhaps another penetration nearby (grey water thru hull, head sink thru hull, etc.?).

Curious what you find!

On Sep 16, 2025, at 08:34, Tim Cooper via Sentoa < mailto:sentoa@lists.sentoa.org sentoa@lists.sentoa.org> wrote:

After cruising this summer we have more leaks than we were aware of so now it is time to address them. I have gone through the archive and seen mentions but no definite solutions. I will report back once leaks are identified and fixed. I would appreciate any help or guidance from all.

1. Saltwater under V-berth, this has existed since we have owned the boat 2018, I think. I dried it out near the thruster battery and up by the thruster. Just sitting no water, after cruising both places have saltwater. The level is always the same because excess flows to bilge pump. We are normally in freshwater so it hasn’t been a big concern but now it is time to dry it out.
2. Saltwater soaked floor in starboard hanging locker or closet. Using a moisture meter I haven’t found the path for the water. The walls in the closet are dry. This summer is the first time we have seen this.
3. Saltwater soaked floor in port hanging locker or closet. I haven’t done any investigation yet but it doesn’t seem to be as bad as the starboard side. This summer is the first time we have seen this.

Thanks

Tim Cooper 37-059 Time To Play

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

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

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

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