Reply
 
Thread Tools Search this Thread Display Modes
 
Old 12-18-2019, 02:34 PM   #21
Guru
 
mvweebles's Avatar
 
City: Saint Petersburg
Vessel Name: Weebles
Vessel Model: 1970 Willard 36 Trawler
Join Date: Mar 2019
Posts: 4,585
Quote:
Originally Posted by Voyager3 View Post
Does anyone know which is better, using SS ball valves or what ever the other ball is made of?? Planning on the SS unless someone knows better.
This is a really good question. I am a huge fan of Groco and I chose their bronze products as much as possible (they also have limited SS products too, but I have never used their SS). But I really don't know if it makes much of a difference - zinc is first in line to take the slack. Most prop shafts are SS, so obviously they do just fine. I'd be interested too in substantive responses.

Peter
__________________
M/V Weebles
1970 Willard 36 Sedan Trawler
mvweebles is online now   Reply With Quote
Old 12-18-2019, 02:43 PM   #22
Guru
 
HopCar's Avatar
 
City: Miami Florida
Vessel Name: Possum
Vessel Model: Ellis 28
Join Date: Aug 2011
Posts: 5,132
Quote:
Originally Posted by mvweebles View Post
Thanks HopCar. I'm putting my order to gather in next day or so. I'm fairly new to TF. Joined a few months ago to get info like this. I really appreciate professionals like yourself contributing. I look forward to doing business with you! I'd never heard of you guys before - Peggy Hall gave y'all a thumbs up. Good enough for me.
I no longer own the business. I retired and sold it about two years ago. It is really nice that Peggy still thinks highly of me. Have you got her book yet?
__________________
Parks Masterson
Retired from Hopkins-Carter Marine Supply
HopCar is offline   Reply With Quote
Old 12-18-2019, 03:08 PM   #23
Guru
 
AKDoug's Avatar
 
City: Kenai, Alaska
Vessel Name: Melanie Rose
Vessel Model: 1999 Willard PH
Join Date: Feb 2013
Posts: 1,170
SS is subject to crevice corrosion in an anaerobic environment, and I would think being in a valve body would be anaerobic... I have never heard of a down side to bronze unless it's not properly grounded or has no sacrificial anode. Bronze is also self lubricating (to a point), I would opt for bronze over stainless. JMO, but if I were you, I would research that a little.
AKDoug is offline   Reply With Quote
Old 12-18-2019, 04:42 PM   #24
Guru
 
HopCar's Avatar
 
City: Miami Florida
Vessel Name: Possum
Vessel Model: Ellis 28
Join Date: Aug 2011
Posts: 5,132
Quote:
Originally Posted by Voyager3 View Post
I had only 1 valve that was glassed over and not done very well either. I chiseled the fiberglass away and removed the thru hull. It was not in a good area and would never be able to be closed in an emergency. Some fiberglass work may be required after you remove it. I am replacing 4 on 1 side that are below the water line and no valves on them?? The Groco valves and backing plates are replacing the existing.
Does anyone know which is better, using SS ball valves or what ever the other ball is made of?? Planning on the SS unless someone knows better.
Groco makes two flanged seacocks, the BV series and the FBV. The BV is made in America and the FBV is imported.

The BV is much heavier and has a stainless ball and stem. It’s not cheap.

The FBV is lighter and has a chrome plated brass ball. It is less expensive. I would prefer the BV but I wouldn’t worry if I had to use the FBV. It would probably outlast me.

Another option is to use Groco’s Flanged Adapter and a good ball valve. That way if the valve goes bad, it’s easy to replace. Price wise I think this falls between the BV and FBV.
__________________
Parks Masterson
Retired from Hopkins-Carter Marine Supply
HopCar is offline   Reply With Quote
Old 12-18-2019, 07:34 PM   #25
Veteran Member
 
City: Shilshole Bay Marina
Join Date: Apr 2019
Posts: 32
Oh sweet. I’m at Shilshole, so I will contact Canal boat yard
Wanna-b is offline   Reply With Quote
Old 12-18-2019, 08:33 PM   #26
Guru
 
syjos's Avatar


 
City: Gig Harbor
Vessel Name: Sandpiper
Vessel Model: Bluewater 40 Pilothouse Trawler
Join Date: Nov 2012
Posts: 2,311
Quote:
Originally Posted by HopCar View Post
Peter, When you bed the backing plates in epoxy, put bolts in the threaded holes to prevent the epoxy from getting into the threads. Once the epoxy hardens just back the bolts out and you’ve got nice clean threads.
Coat the bolt with vaseline or grease before inserting into the holes. Otherwise, the epoxy may wick up the thread.
syjos is offline   Reply With Quote
Old 12-18-2019, 10:50 PM   #27
Guru
 
syjos's Avatar


 
City: Gig Harbor
Vessel Name: Sandpiper
Vessel Model: Bluewater 40 Pilothouse Trawler
Join Date: Nov 2012
Posts: 2,311
Quote:
Originally Posted by angus99 View Post
I respectfully disagree. The Groco backing plates, if properly bonded with epoxy or fiberglassed to the hull, including fillets around the circumference, are considered by the experts I consulted to be the equal of through-bolting. Also, if you’re using the Groco through hull and flange (see HopCar’s post above), the NPT threads match each other (unlike most older installations which try to force-fit both straight and tapered threads) and they take a much deeper bite. This deeper connection adds considerable strength to the overall installation.
I agree.

I've never through bolted seacocks. With the hull and bonded backing plate sandwiched between a straight thread flanged seacock and a straight thread mushroom thru-hull trimmed to the proper length, it is unnecessary to through bolt. I do install one screw through a hole to prevent the seacock from unscrewing if using a wood backing plate. And a bolt if using Groco's backing plate.
syjos is offline   Reply With Quote
Old 12-19-2019, 06:54 AM   #28
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 22,553
It would seem the photo sea cock (# 14) is properly thru bolted or the GRP backing plate is threaded or somehow the bolt is finding its mounting nut and the excess bolt length is not poking a hole in the bottom.

A sea cock may need to take the weight of a flying tool box and is expected to be functional if a thru hull is removed for inspection and re installed.

It would seem the mount bolts are SS another risk in seawater.
FF is offline   Reply With Quote
Old 12-19-2019, 08:43 AM   #29
Guru
 
City: Rochester, NY
Vessel Name: Hour Glass
Vessel Model: Chris Craft Catalina 381
Join Date: Aug 2019
Posts: 5,714
Quote:
Originally Posted by FF View Post
It would seem the photo sea cock (# 14) is properly thru bolted or the GRP backing plate is threaded or somehow the bolt is finding its mounting nut and the excess bolt length is not poking a hole in the bottom
From what's been described (and what I know about the Groco backing plates), the setup in post 14 is a threaded backing plate. So the plate is epoxied to the hull and then the flange is bolted to the plate. Done correctly, it's just about as strong as through bolting (certainly strong enough) and without the extra holes in the hull.
rslifkin is offline   Reply With Quote
Old 12-19-2019, 09:41 AM   #30
Guru
 
angus99's Avatar
 
City: Signal Mtn., TN
Vessel Name: Stella Maris
Vessel Model: Defever 44
Join Date: Feb 2012
Posts: 2,692
Quote:
Originally Posted by FF View Post
It would seem the photo sea cock (# 14) is properly thru bolted or the GRP backing plate is threaded or somehow the bolt is finding its mounting nut and the excess bolt length is not poking a hole in the bottom.

A sea cock may need to take the weight of a flying tool box and is expected to be functional if a thru hull is removed for inspection and re installed.

It would seem the mount bolts are SS another risk in seawater.
Fred, it seems you have a lot of concerns about these assemblies. So let’s address them one-by-one.

The three bolts you mention only go through the backing plate—not the hull—and attach to captive nuts in the backing plates. They are sized to not protrude beneath the backing plate and they are not in contact with seawater. The backing plates are a composite material that doesn’t absorb water and they are epoxied to the hull or, in my photo, to the sea chest. The mushroom, using matching threads, engages the flange almost 1 inch deep, adding considerable strength—vastly more than the two or three threads holding Seacocks to mushrooms in many older boats. Both the mushroom and the flanged adapter are embedded in 5200, but the valve is easily removed for inspection and replacement.

I know these are not old school and you have strong opinions about them, but short of throwing a tool box at them, I believe the engineers at Groco and Rod Collins do have a clue about what makes for a strong through hull assembly. Rod has subjected a flanged base/valve assembly bolted only to a 1/2” GPO backing plate to 1000 lbs of pressure.

https://marinehowto.com/seacock-backing-plates/

Now Groco uses a different material for their backing plates but their tech support folks say the flanged adapter valve assembly—using a fully engaged mushroom—meets or exceeds the ABYC shear test.

So can we put to rest the notion that these are somehow inferior installations?
angus99 is offline   Reply With Quote
Old 12-19-2019, 10:57 AM   #31
Guru
 
syjos's Avatar


 
City: Gig Harbor
Vessel Name: Sandpiper
Vessel Model: Bluewater 40 Pilothouse Trawler
Join Date: Nov 2012
Posts: 2,311
In the past, wood was used for seacock backing plates. The purpose for the backing plate was to distribute the load and add thickness.

A secondary function of a wood backing plate was to stop leaks. The theory was that in the event of a leak, water would swell the wood backing plate and stop the leak.

I've witnessed leaking seacocks stop leaking after an hour or so after splashing because of the wood blocks swelling.

Modern sealants and caulk probably mitigate the seacock leak but I still use wood backing blocks. I have installed the Groco plates on client's boat when requested without issue.
syjos is offline   Reply With Quote
Old 12-19-2019, 11:53 AM   #32
DDW
Guru
 
City: San Francisco
Join Date: Apr 2018
Posts: 2,443
Personally I would replace them with the Forespar plastic OEM ones. They do not corrode ever, do not require bonding, are less likely to evaporate in a lightening strike, and exceed the ABYC and CG required strengths. I would not trust the alloy in a 'bronze' one, even stamped Groco, unless each and every fitting was shot with an XRF gun.
DDW is offline   Reply With Quote
Old 12-19-2019, 12:00 PM   #33
Guru
 
angus99's Avatar
 
City: Signal Mtn., TN
Vessel Name: Stella Maris
Vessel Model: Defever 44
Join Date: Feb 2012
Posts: 2,692
Quote:
Originally Posted by syjos View Post
In the past, wood was used for seacock backing plates. The purpose for the backing plate was to distribute the load and add thickness.

A secondary function of a wood backing plate was to stop leaks. The theory was that in the event of a leak, water would swell the wood backing plate and stop the leak.

I've witnessed leaking seacocks stop leaking after an hour or so after splashing because of the wood blocks swelling.

Modern sealants and caulk probably mitigate the seacock leak but I still use wood backing blocks. I have installed the Groco plates on client's boat when requested without issue.
In my case, some of the wooden backing plates were pulpy or poorly adhering to the fiberglass. I could peel some off easily by hand. The original Groco rubber plugged Seacocks (excellent in their day, but parts are no longer available) were not bolted to anything! They were simply held in place by whatever thread connection they could achieve with the through hull mushroom (using dissimilar threads) and some weak mastic. I couldn’t get them out of the boat fast enough and replaced all 13 (below the waterline) with Groco flanged adapters — thereby enabling Parks’ early retirement .
Attached Thumbnails
BC2ECF03-4222-45C1-BB6C-466C775513B1.jpg   BDD12F1C-323F-43E1-B11D-A434643027BF.jpg  
angus99 is offline   Reply With Quote
Old 12-19-2019, 08:41 PM   #34
Guru
 
HopCar's Avatar
 
City: Miami Florida
Vessel Name: Possum
Vessel Model: Ellis 28
Join Date: Aug 2011
Posts: 5,132
Quote:
Originally Posted by angus99 View Post
In my case, some of the wooden backing plates were pulpy or poorly adhering to the fiberglass. I could peel some off easily by hand. The original Groco rubber plugged Seacocks (excellent in their day, but parts are no longer available) were not bolted to anything! They were simply held in place by whatever thread connection they could achieve with the through hull mushroom (using dissimilar threads) and some weak mastic. I couldn’t get them out of the boat fast enough and replaced all 13 (below the waterline) with Groco flanged adapters — thereby enabling Parks’ early retirement .
I did love shipping that order!
__________________
Parks Masterson
Retired from Hopkins-Carter Marine Supply
HopCar is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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


» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 09:50 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2022, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012