Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 13-08-2014, 20:49   #1
Registered User
 
Scare_Rab's Avatar

Join Date: Nov 2009
Location: Otautahi, Aotearoa
Boat: Alan Pape. Ebbtide 33'
Posts: 104
Images: 5
Do we Always Close the Exhaust Valve when Ocean Sailing

my new 33' steel yacht has a seacock / valve farback just before the exhaust exits through the stern. Meant to prevent seawater travelling back UP and into the engine , when sailing. Photo attached. Not that easy to get to: a tight squeeze for me - 6'4" 240lb. I have read of one instance where, after severe weather, the diesel had been badly damaged coz of water entering combustion chamber. Question? Do we all , as a matter of course " ALWAYS " shut such a valve when heading off soundings?
Attached Thumbnails
Click image for larger version

Name:	image.jpg
Views:	268
Size:	361.9 KB
ID:	86587  
__________________

__________________
Scare_Rab is offline   Reply With Quote
Old 13-08-2014, 21:02   #2
Senior Cruiser
 
DeepFrz's Avatar

Cruisers Forum Supporter

Join Date: Mar 2006
Location: Winnipeg
Boat: None at this time
Posts: 7,930
Re: do we always close the exhaust valve when Ocean sailing

How high does the exhaust hose rise from the seacock before it starts the slope down to the water lift muffler and is the exhaust riser/injection elbow below the waterline?

Whether you turn your seacock off all the time or just in steep following seas depends a lot on the design of your exhaust system. A big problem with flooding the engine is the anti-siphon valve between the heat exchanger and the injection elbow.

If the engine exhaust riser is below the waterline it may be wise to also turn off the water inlet seacock. Some people attach the keys to the seacock as a reminder to open it/them before you can start the engine.

https://www.google.ca/search?q=sailb...cs%3B490%3B240
__________________

__________________
The Blue Dot Campaign. This Changes Everything.
DeepFrz is offline   Reply With Quote
Old 13-08-2014, 21:10   #3
Registered User
 
Panope's Avatar

Join Date: Sep 2012
Location: Washington State
Boat: Colvin, Saugeen Witch (Aluminum), 34'
Posts: 1,593
Re: do we always close the exhaust valve when Ocean sailing

Mine gets closed EVERY TIME I turn off the engine.

Steve



Panope is online now   Reply With Quote
Old 13-08-2014, 21:14   #4
Senior Cruiser
 
DeepFrz's Avatar

Cruisers Forum Supporter

Join Date: Mar 2006
Location: Winnipeg
Boat: None at this time
Posts: 7,930
Re: do we always close the exhaust valve when Ocean sailing

Panope, that is neat. I haven't seen one like that. Is it your invention?
__________________
The Blue Dot Campaign. This Changes Everything.
DeepFrz is offline   Reply With Quote
Old 13-08-2014, 21:30   #5
Registered User
 
Panope's Avatar

Join Date: Sep 2012
Location: Washington State
Boat: Colvin, Saugeen Witch (Aluminum), 34'
Posts: 1,593
Re: do we always close the exhaust valve when Ocean sailing

Quote:
Originally Posted by DeepFrz View Post
Panope, that is neat. I haven't seen one like that. Is it your invention?
Yep. The flap is a scrap of Starboard and the counter weight is lead. I welded the "ears" to the boat during my rebuild and before the final painting. Easy peazy.

Steve
Panope is online now   Reply With Quote
Old 13-08-2014, 21:35   #6
Senior Cruiser
 
DeepFrz's Avatar

Cruisers Forum Supporter

Join Date: Mar 2006
Location: Winnipeg
Boat: None at this time
Posts: 7,930
Re: do we always close the exhaust valve when Ocean sailing

Very nice.
__________________
The Blue Dot Campaign. This Changes Everything.
DeepFrz is offline   Reply With Quote
Old 13-08-2014, 21:37   #7
Registered User
 
Snowpetrel's Avatar

Join Date: Jul 2012
Location: Hobart
Boat: Alloy Peterson 40
Posts: 3,071
Re: do we always close the exhaust valve when Ocean sailing

I am planning to add a drain to the wet box. If you don't know the boat its a good idea to close the valve for offshore but a well designed system shouldn't need it. Remember theirs still slot of water in the system that can cause problems. Nice system Panope
__________________
My Ramblings
Snowpetrel is offline   Reply With Quote
Old 13-08-2014, 22:01   #8
Registered User
 
Panope's Avatar

Join Date: Sep 2012
Location: Washington State
Boat: Colvin, Saugeen Witch (Aluminum), 34'
Posts: 1,593
Re: do we always close the exhaust valve when Ocean sailing

Thanks Phil, Snowpetrel,

I made no attempt to create any kind of seal. I figure the flap will block better than 90% of the water volume and close to 100% of the water energy (wave). Water will have to travel about 18" upwards and about 4 feet forward in order to make it over the hump.

Someday, If I ever get in some decent following seas, I will open the drain valves of the water lift muffler and monitor the output. Only then will I know if the idea is really working or not.

Steve
Panope is online now   Reply With Quote
Old 14-08-2014, 04:22   #9
Registered User
 
Snowpetrel's Avatar

Join Date: Jul 2012
Location: Hobart
Boat: Alloy Peterson 40
Posts: 3,071
Re: do we always close the exhaust valve when Ocean sailing

What about making a stick with two prongs to turn the valve from outside the locker?

Sent from my GT-P5210 using Cruisers Sailing Forum mobile app
__________________
My Ramblings
Snowpetrel is offline   Reply With Quote
Old 14-08-2014, 05:23   #10
Registered User

Join Date: Aug 2011
Posts: 17
Re: do we always close the exhaust valve when Ocean sailing

Maybe another approach is an anti-siphon loop on the exhaust

I would imagine a loop plus an exhaust flap would be more than sufficient

Josh


Sent from my iPhone using Cruisers Sailing Forum
__________________
engineer_sailor is offline   Reply With Quote
Old 14-08-2014, 05:28   #11
Moderator
 
a64pilot's Avatar

Cruisers Forum Supporter

Join Date: Oct 2013
Location: Albany Ga.
Boat: Island Packet 38
Posts: 17,045
Re: do we always close the exhaust valve when Ocean sailing

Could also use a linear actuator to close the valve electrically, like this one, that way all you have to do is flip a switch
InstallBay FLIN8 8 Inch Linear Actuator with 12 Volt and 175 Pounds Capacity - IST14-FLIN8
__________________
a64pilot is offline   Reply With Quote
Old 14-08-2014, 10:31   #12
Registered User
 
S/V Alchemy's Avatar

Join Date: May 2008
Location: Toronto
Boat: Custom 41' Steel Pilothouse Cutter
Posts: 4,576
Re: do we always close the exhaust valve when Ocean sailing

Quote:
Originally Posted by Panope View Post
Yep. The flap is a scrap of Starboard and the counter weight is lead. I welded the "ears" to the boat during my rebuild and before the final painting. Easy peazy.

Steve
Really clever, Panope.

As for the original question, yes, if at all possible. You have a few options, however: a sort of flap that will stop all but a direct wave combined with a stern "squat" from letting much water in; an improved "gooseneck" to increase the height the water needs to rise to roll back down to the waterlift; an electric solenoid seacock to close this valve when the engine is switched off, or a mechanical linkage allowing you to close it and open it from some distance away by pushing and pulling on threaded rod or something. You could arguably use a Morse/Teleflex cable to do this as well. Of course, if you forget to open it and start the engine, things get ugly fast.
__________________
Can't sleep? Read www.alchemy2009.blogspot.com for fast relief. Can't read? Avoid www.volumesofsalt.blogspot.com, because it's just personal reviews of sea books.
S/V Alchemy is offline   Reply With Quote
Old 14-08-2014, 10:38   #13
Senior Cruiser
 
FSMike's Avatar

Cruisers Forum Supporter

Join Date: Aug 2009
Location: Bahamas/Florida
Boat: Solaris Sunstar 36' catamaran
Posts: 2,654
Images: 5
Re: do we always close the exhaust valve when Ocean sailing

Quote:
Originally Posted by Scare_Rab View Post
----
Question? Do we all , as a matter of course " ALWAYS " shut such a valve when heading off soundings?
The only thing "we all" on Cruisers Forum seem to agree on is to never be unanimous about anything.
I never shut my seacock when the boat is moving. It might prove embarrassing if I needed to crank the engine in a hurry.
__________________
Sail Fast Live Slow
FSMike is offline   Reply With Quote
Old 14-08-2014, 10:47   #14
Senior Cruiser
 
Cheechako's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 19,359
Re: do we always close the exhaust valve when Ocean sailing

I have to say I've never shut an exhaust seacock in 40 years. I've had a few, but they were meant to be shut for survival conditions only. It is important to have a loop or something. I had one engine problem simply from little wavelets hitting the stern at the right angle while docked... gradually pumping water into the exhaust. I saved the engine but bent a pushrod on the aft cylinder when I started it.
__________________
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard











Cheechako is offline   Reply With Quote
Old 14-08-2014, 20:02   #15
Registered User
 
Snowpetrel's Avatar

Join Date: Jul 2012
Location: Hobart
Boat: Alloy Peterson 40
Posts: 3,071
Re: do we always close the exhaust valve when Ocean sailing

Got to be honest and say I normally don't bother on most boats. I did on one delivery because the system looked suspect and it was easy to reach. Hung the keys on the exhaust valve so as not to forget. I also closed the water intake on this boat. I wouldn't be supprised if 90% of the time water actually came in through the seacock, and a faulty vented loop.

You system seems good from the photo, nice high loop and 90 degree up just after the seacock. Does your engine have decompressors? If it does its a good habit to crank it over with the valves open to blow out any water and prelube the engine. Stops expensive damage if water has got into the engine for some reason.

Offshore engines only needed in calms and maybe for mob. So no great harm in taking extra precautions, specially if you are singlehanded. Inshore, best not to close it unless its really dodgy.
__________________

__________________
My Ramblings
Snowpetrel is offline   Reply With Quote
Reply

Tags
exhaust, sail, sailing

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
Replaced faulty T&P relief valve with pressure relief valve on Seaward water heater conestablo Plumbing Systems and Fixtures 4 27-05-2013 08:39
How Close to Shore Is Too Close While Hove-to ? oldman66 General Sailing Forum 91 21-10-2011 18:25
Y-Valve Question: Is there a 3-Directional Valve Out there to Buy ? svpolaris Plumbing Systems and Fixtures 14 05-11-2010 20:28
A Valve in Exhaust System SkiprJohn Engines and Propulsion Systems 13 03-11-2009 12:27
Too Close! WAY TOO CLOSE! Anchoring Near Jerks MarkJ Anchoring & Mooring 106 20-05-2009 13:58



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 06:34.


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.