Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 21-08-2017, 12:39   #1
Registered User
 
SVRocinante's Avatar

Join Date: Feb 2005
Location: Where ever the wind blows - Currently Herrington Harbour North
Boat: Hanse, 400e - 40ft
Posts: 138
Re-bedding a Thru-hull - how big a deal?

Good day all

OK, I'm not trying to be cheap here, but I just got a quote of $400 to re-bed one of my thru-hulls that is leaking (galley sink drain) add to that the bit over $500 to haul, block & launch and we're talking $900+

It's not going to kill me, but also not chump change.

Now, I don't think I can help the $500 part, but $400 seems a bit excessive to take out and re-bed a thru-hull. Is it really a 3hr job?

As best I can tell, I need to unclamp the hose, unscrew the valve, undo the nut, knock out the thru-hull; clean and reverse the process with new bedding compound or butyl tape?

Again, not bitching, just asking from those that have done it themselves in order to make an informed decision to farm it out or go the DIY route.

BTW, assuming I go the DIY route, how do I test to ensure that I did it "correctly"? i.e. I sure as heck don't want to pay an additional $500 bucks to haul the boat out again!

Thanks!
__________________

__________________
Carlos & Maria
S/V Rocinante
SVRocinante is offline   Reply With Quote
Old 21-08-2017, 12:58   #2
Senior Cruiser
 
Sailmonkey's Avatar

Cruisers Forum Supporter

Join Date: Sep 2009
Location: Houston
Boat: '76 Allied Seawind II, 32'
Posts: 5,543
Re: Re-bedding a Thru-hull - how big a deal?

You've got the gist of it. I replaced three seacocks with groco flange adapters and ball valves by myself in a little over 4 hours. I would think you could do a single mushroom fitting in less than an hour if you plan ahead.
__________________

__________________
Sailmonkey is online now   Reply With Quote
Old 21-08-2017, 13:02   #3
Registered User
 
SVRocinante's Avatar

Join Date: Feb 2005
Location: Where ever the wind blows - Currently Herrington Harbour North
Boat: Hanse, 400e - 40ft
Posts: 138
Re: Re-bedding a Thru-hull - how big a deal?

Quote:
Originally Posted by Sailmonkey View Post
You've got the gist of it. I replaced three seacocks with groco flange adapters and ball valves by myself in a little over 4 hours. I would think you could do a single mushroom fitting in less than an hour if you plan ahead.
Much Thanks!

Any thoughts on testing? Is it even possible to test?

Thanks!
__________________
Carlos & Maria
S/V Rocinante
SVRocinante is offline   Reply With Quote
Old 21-08-2017, 13:09   #4
Registered User
 
John_Trusty's Avatar

Join Date: Oct 2014
Location: Michigan, USA
Boat: Catalina 36 (1999)
Posts: 187
Re: Re-bedding a Thru-hull - how big a deal?

I agree that 3 hours work is a high estimate for a single 1-inch through-hull, particularly if the outside is a mushroom and just sits on the surface (no fairing etc.) and there is no additional repair work (a simple swap out with bedding compound). To get a better idea of the job, I suggest MaineSail's excellent photo tutorial: Welcome To MarineHowTo.com Photo Gallery by Compass Marine How To at pbase.com

That said, the job can get more complex if you need to do some epoxy work such as replacing and adhering a new backing block. I assume that you're going to do this on a short-haul - just leaving the boat in the slings while the work is done, not putting it on stands?

You'll want to use a one-part polyurethane such as 3M 4000 or 4200 for bedding, not butyl which is not really rated for below waterline. A very small amount of this on the threads also works better than that silicone tape for below-waterline too. Testing? Put enough 3M stuff around the the hole and under the mushroom head - it's foolproof.
__________________
John Trusty

Better to trust the man who is frequently in error than the one who is never in doubt." -- Eric Sevareid
John_Trusty is offline   Reply With Quote
Old 21-08-2017, 13:17   #5
Senior Cruiser
 
Sailmonkey's Avatar

Cruisers Forum Supporter

Join Date: Sep 2009
Location: Houston
Boat: '76 Allied Seawind II, 32'
Posts: 5,543
Re: Re-bedding a Thru-hull - how big a deal?

Quote:
Originally Posted by SVRocinante View Post
Much Thanks!

Any thoughts on testing? Is it even possible to test?

Thanks!
Testing isn't really feasible, you'll want enough 4200/5200 to smush out. Clean it up and splash the boat. If you try to skimp on the sealant you may end up with leaks......so use a little too much and deal with the mess with a roll of paper towels and some mineral spirits for the final light wipe. Do not let the mineral spirits saturate anything, just use it lightly for the final wipe.
__________________
Sailmonkey is online now   Reply With Quote
Old 21-08-2017, 13:24   #6
Registered User
 
Suijin's Avatar

Join Date: Feb 2013
Location: Annapolis MD; currently in Oriental NC
Boat: Valiant 40
Posts: 2,500
Re: Re-bedding a Thru-hull - how big a deal?

I have seen quite a few three hour thru-hull jobs, trust me. Because often what you are doing is fixing a poor prior install. That said, if it was well installed and you can wrench it out, it should go pretty quick.

If you do it properly the chances of it leaking are next to zero. I would say the critical factor is how well the new thru-hull fits the existing hole.

Make sure you change the old backing plate, assuming it's wood.
__________________
Suijin is offline   Reply With Quote
Old 21-08-2017, 14:00   #7
Registered User
 
SVRocinante's Avatar

Join Date: Feb 2005
Location: Where ever the wind blows - Currently Herrington Harbour North
Boat: Hanse, 400e - 40ft
Posts: 138
Re: Re-bedding a Thru-hull - how big a deal?

Thanks for the link John_Trusty and for the 4200 suggestion - as you can tell, I hadn't quite gotten that far in figuring out what to do

Thanks for the additional info on sealant and cleanup Sailmonkey

Thanks Suijin - right now reinstalling existing thru-hull, at first glance it looks to be in perfect shape... pretty sure the only issue is the bedding. Of course, once it's out if I see anything to the contrary, I'll replace it. No backing plates...

All that said, now I'm a bit concerned that they might have used 5200 - have heard horror stories of how "permanent" a bond that makes!

Thanks again folks!
__________________
Carlos & Maria
S/V Rocinante
SVRocinante is offline   Reply With Quote
Old 21-08-2017, 14:26   #8
Registered User
 
SVRocinante's Avatar

Join Date: Feb 2005
Location: Where ever the wind blows - Currently Herrington Harbour North
Boat: Hanse, 400e - 40ft
Posts: 138
Re: Re-bedding a Thru-hull - how big a deal?

Quote:
Originally Posted by John_Trusty View Post
...To get a better idea of the job, I suggest MaineSail's excellent photo tutorial: Welcome To MarineHowTo.com Photo Gallery by Compass Marine How To at pbase.com
...
Boy oh boy did you just open up a can of worms!

Unfortunately, my "thru-hulls" look like the one on the right & I'm no longer ignorant of the fact that it is not the "preferred" way to do it!

__________________
Carlos & Maria
S/V Rocinante
SVRocinante is offline   Reply With Quote
Old 21-08-2017, 15:43   #9
Senior Cruiser
 
Sailmonkey's Avatar

Cruisers Forum Supporter

Join Date: Sep 2009
Location: Houston
Boat: '76 Allied Seawind II, 32'
Posts: 5,543
Re: Re-bedding a Thru-hull - how big a deal?

Quote:
Originally Posted by SVRocinante View Post
Boy oh boy did you just open up a can of worms!

Unfortunately, my "thru-hulls" look like the one on the right & I'm no longer ignorant of the fact that it is not the "preferred" way to do it!



I'll bet if you really get to looking into it your valves are lesser quality as well when compared to the groco stuff.....just gotta pick your battles at the appropriate times.
__________________
Sailmonkey is online now   Reply With Quote
Old 21-08-2017, 16:15   #10
Registered User

Join Date: Oct 2016
Location: Cape Haze,FL
Boat: Carver,Cobia,Nacra
Posts: 76
Re: Re-bedding a Thru-hull - how big a deal?

Yes, it is expensive. So is your boat sinking when you are not aboard.
Sounds like you should have them remove/replace every thru hull. Your mobilization costs for 1 thru hull is high, take advantage of your haul out and get as much submerged work done as possible!
__________________
flyingfin is offline   Reply With Quote
Old 21-08-2017, 17:34   #11
Registered User

Join Date: Jan 2008
Location: SF Bay Area (Boat in La Paz)
Boat: Valiant V40
Posts: 406
Re: Re-bedding a Thru-hull - how big a deal?

I might suggest that you at least replace the thru hull even if you do not replace the ball valve. The thru hull is the weakest part and any corrosion damage there could come back to haunt you. Also, keep the inside (exposed) portion of the thru hull as short as reasonably possible (consistent with full thread engagement in the valve). This keeps the breaking moments as low as possible.
__________________
jamhass is offline   Reply With Quote
Old 21-08-2017, 18:08   #12
Registered User
 
Ziggy's Avatar

Join Date: Apr 2008
Location: U.S., Northeast
Boat: Contessa 32
Posts: 1,415
Images: 2
Re: Re-bedding a Thru-hull - how big a deal?

Quote:
Originally Posted by jamhass View Post
I might suggest that you at least replace the thru hull even if you do not replace the ball valve. The thru hull is the weakest part and any corrosion damage there could come back to haunt you. Also, keep the inside (exposed) portion of the thru hull as short as reasonably possible (consistent with full thread engagement in the valve). This keeps the breaking moments as low as possible.
If you're going to haul out and take off a thru hull, you might as well replace the valve also. If there is no proper backup block, you should plann on adding one. And you might as well check all your other thru hulls and valves. Might be a good time to paint the bottom and service whatever else needs servicing too. After it's all done, $900 will seem ridiculously low.

By the way, when I did my thru hulls, one of them was seized so tight to the valve I couldn't budge it and eventually I had to grind it out. That certainly took longer than 3 hrs.
__________________
... He knows the chart is not the sea.
-- Philip Booth, Chart 1203
Ziggy is online now   Reply With Quote
Old 21-08-2017, 20:16   #13
Registered User

Join Date: Oct 2007
Location: virginia
Boat: islandpacket
Posts: 1,791
Re: Re-bedding a Thru-hull - how big a deal?

Quote:
Originally Posted by SVRocinante View Post
Boy oh boy did you just open up a can of worms!

Unfortunately, my "thru-hulls" look like the one on the right & I'm no longer ignorant of the fact that it is not the "preferred" way to do it!

The one on the right are like mine and came from the factory like that.
The real problem is the threads are same size but different threads.
When I found the valve was only threaded on by two turns I replaced them all.
The thru hulls is a streight thread the valve thread is tapered. The valve to hose adapter is fine as it is tapered to tapered. The groco flange adapter is what's needed, the one on the left, it has straight threads on the bottom for the thru hulls and tapered on top for the valve.
You cannot have a strong connection putting a straight thread in a tapered hole or visa versa. Straight
__________________
That derelict boat was another dream for somebody else, don't let it be your nightmare and a waste of your life.
Badsanta is offline   Reply With Quote
Old 21-08-2017, 20:43   #14
Registered User
 
UNCIVILIZED's Avatar

Join Date: Jun 2014
Location: Up the mast, looking for clean wind.
Boat: Currently Shopping, & Heavily in LUST!
Posts: 5,369
Re: Re-bedding a Thru-hull - how big a deal?

I’d call it lucky if you can get the job done in under 3hrs, unless the system has been recently serviced, & well maintained since then. And if things haven’t, then it’s quite easy for such a job to turn into one taking several days.The reasons for which I could type a couple of pages of text listing.
Yes, in theory it’s a simple job. But, if there are any hiccups along the way it can turn into an Alice In Wonderland type misadventure.
__________________

The Uncommon Thing, The Hard Thing, The Important Thing (in Life): Making Promises to Yourself, And Keeping Them.
UNCIVILIZED is offline   Reply With Quote
Old 21-08-2017, 21:18   #15
Registered User
 
JerseyJoe's Avatar

Join Date: Sep 2014
Location: NJ/NY
Boat: 1978 Rafiki 35
Posts: 126
Images: 1
Re: Re-bedding a Thru-hull - how big a deal?

Agree with Ziggy on replacing the whole setup if leaking. including installing new backing plate, flanged seacock and grounding wire(if corroded). And yes they can be time consuming if need to grind or cut out as Ziggy said.

I just did 7 of 11 of them and only one came out easy. Make sure to mark the flange on dry fit to drill for grounding wire if not already pre-drilled and that thru-hull has enough thread to accommodate both backing plate and flange or if needs to be cut.

And as Sailmonkey said go extra on the 4200/5200 to smear the external seal even though messier. Also lube the seacock prior to install even though new.

Well worth the price if done right and gives you decades of service if maintained properly.
__________________

__________________
JerseyJoe is offline   Reply With Quote
Reply

Tags
hull, bed

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Deal or no deal captainbri Monohull Sailboats 4 03-04-2014 22:40
Make a Deal-Get a Deal- Used Boat Gear lynnrgardner Commercial Posts 0 09-12-2013 10:42
Exhaust: Thru Hull? Not Thru Hull? steel Powered Boats 12 18-10-2012 21:14
How Big/many does a thru hull need to be? xymotic Construction, Maintenance & Refit 16 08-04-2012 07:12


Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 17:34.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.