Raw Water Seacock

Feb 8, 2014
1,300
Columbia 36 Muskegon
The original engine intake in my Columbia 36 was in the engine space but back about even with the shaft coupler. A real bear to get to. And it was a gate valve that wouldn't turn. One of the first things I did to the boat was change all the through hulls to Marelon seacocks. I moved that one right up front inside the engine cover. I also cut a hatch in the cockpit sole because there wasn't clearance to take the engine valve cover off. I can check the oil and coolant and reach the seacock through that hatch. Very convenient.
When we were living aboard we left the seacocks open all the time. Now we're back to weekends and we close everything when we leave. We're on a mooring and going down in 30 feet would be a lot worse than six feet in a slip.
 

Nick

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Dec 8, 2015
33
x 1 x
I would not want that valve to fail unattended for one. Also having the valve open allows critters to enter the system and build colonies in the heat exchanger and other places within the system... for those that fresh water flush their system this seacock would need to be close, etc. Like my other seacocks when we are not on the boat they are all closed.
 
Feb 8, 2014
1,300
Columbia 36 Muskegon
Opening and closing them frequently also keeps them from getting stuck. The Marelon and rubber plug kind are prone to this. You really don't want a busted hose on a stuck seacock.
 
Jun 5, 2010
1,107
Hunter 25 Burlington NJ
Mike, I don't know the 280; but if it works then that's the answer.

I was just gonna say what Capt JGW said too. This is especially true with Marelon ones.

As far as closing it, I tend to advocate having a checklist and following it (yes; I was a pilot once); and on that list is definitely 'close all seacocks when leaving boat'. Why take the risk of a hose clamp failing? (I have seen new ones do this!) Also it keeps aquatic creepies from finding a home, leaving shells and clogging up your intake line (before the strainer, which happens). My point about location is that, if it's hard to get to, you'll just omit taking this important safety precaution and then it really doesn't matter, should you have a engine fire-- the boat will now be assured of going down. Also, if you keep shutting all the others dutifully, you assure yourself the leak won't be any of those; but the law of fatalism says that the one seacock you leave open and 'hope' (my mother's favorite crisis-coping word) won't be a problem will be the one on which the hose fails, because the law of fatalism says you deserved it.

FYI: the law of fatalism is: If you plan for the best, it'll never happen; if you plan for the worst, it'll never happen.

If you follow my drift; it's really a no-brainer.:clap:

BTW as to bilge pumps, read the Seaworthy book in which Bob Adriance says their exits should always be located as high in the hull as possible, for all sorts of reasons even the most logical people didn't think of. Related to this thread, one reason would be because they do not require seacocks and so can never be accidentally or inappropriately closed, leaving them always open for use (like when you are not on the boat). Gotta give the poor boat a way to save herself!
 
Jun 5, 2010
1,107
Hunter 25 Burlington NJ
Nick, I wouldn't bet on that hose outliving anyone. The 'fatalism rule' (see my other post) says that it's too much a risk to take. Granted this is the one hose (besides the holding-tank discharge line) that most people never want to have to remove (I use a pneumatic cutting wheel), but, again, that is no excuse to pretend it is always in reliable condition. Replace it every about five years and be glad you have that luxury. The boat won't do you any good sitting under 12 ft of water at the bottom of what used to be your slip.
 

Nick

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Dec 8, 2015
33
x 1 x
Diana... I have recently replaced this hose along with the raw water pump to heat exchanger last year.... the original hoses were there since the day the boat left the factory and they were still 'usable'? But you're right the hoses should be replaced on a regular basis but depends on usage of the boat... not 12 ft under... yet.
 

HMT2

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Mar 20, 2014
899
Hunter 31 828 Shoreacres, TX
On our '83 H31, we keep our raw water seacock closed when we are away. To ensure we don't burn up the engine by forgetting to open it we simply keep the ignition key hung on the closed seacock handle. Grab the key, open the seacock --return the key close the seacock. It gets exercised regularly so no worries about it freezing up. Works for us.
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
but why close them in the 1st place?
Seacock related sinking here in Maine...



Boat US:

"If the boat must be left in the water, the thru-hulls have to be protected by closing all seacocks and gate valves.

Failure to close thru-hulls is a major cause of loss in the BoatU.S. insurance program. In a recent study of 40 winter-related claims, seacocks or gate valves left open caused or contributed to the sinking of seven of the boats in the sample group.

If the boat must be left in the water, the thru-hulls have to be protected by closing all seacocks and gate valves."


"This boat in Maryland sank when it's plastic thru-hull was shoved underwater by the weight of the snow. the intake was broken by ice"


This boat sank due to a failed sea strainer, which is after the seacock. 100% preventable, if the seacock had been closed...
 
Jun 5, 2010
1,107
Hunter 25 Burlington NJ
The worst 'foolish economy' is when cheap plastic through-hulls are used too close to the waterline. That said, my not-so-inconsiderable opinion is that 'too close to the waterline' means 'anywhere in the topsides'. I wouldn't trust a cheap plastic Perko through-hull on an aquarium. Anything holding seawater out of the boat should be bronze or Marelon, each having its own very good reasons.

The Seaworthy book details numerous cases of failed plastic through-hulls. We are sailors, with sailboats-- we don't follow the guidelines of outboard-powered motorboats (that use cheap nylon through-hulls all the time, even in inaccessible spaces). Attention to matters like this is what sets us above the rest.
 
Jun 5, 2010
1,107
Hunter 25 Burlington NJ
The original engine intake in my Columbia 36 was in the engine space but back about even with the shaft coupler. A real bear to get to. And it was a gate valve that wouldn't turn. One of the first things I did to the boat was change all the through hulls to Marelon seacocks. I moved that one right up front inside the engine cover. I also cut a hatch in the cockpit sole because there wasn't clearance to take the engine valve cover off. I can check the oil and coolant and reach the seacock through that hatch. Very convenient.
When we were living aboard we left the seacocks open all the time. Now we're back to weekends and we close everything when we leave. We're on a mooring and going down in 30 feet would be a lot worse than six feet in a slip.
Everything you say here I'd agree with. If you were running for office I'd vote for you. Thanks for this.
 
Jun 5, 2010
1,107
Hunter 25 Burlington NJ
On our '83 H31, we keep our raw water seacock closed when we are away. To ensure we don't burn up the engine by forgetting to open it we simply keep the ignition key hung on the closed seacock handle. Grab the key, open the seacock --return the key close the seacock. It gets exercised regularly so no worries about it freezing up. Works for us.
That's a VERY good idea!
 
Mar 20, 2014
12
hunter 28 Tyler
Last year I helped a friend raise his boat after is sunk because of a valve being left open! his comment ( It's hard to get to and have owned this boat for 15 years and never closed the valve why would it sink now ? ) no anti siphon valve on the head
I think that the total time spent on the re float and clean up would have far exceeded the time spent closing the HARD to get to valve. The term hard is relative NOTE put your ignition key on the handle of the engine valve ,ask me why??? Many years ago I purchased a boat that had a check list on the last hatch board I pulled it off and about he 3rd time leaving the boat as I clicked the lock closed I remembered the last thing on the list ( GET KEY'S) it was a pad lock, no one at he marina, no cell phone, gate to marina locked, after leaving my battery's on a couple times lately I'am rethinking the list idea !!
 
Oct 26, 2010
1,881
Hunter 40.5 Beaufort, SC
Benny "not having to worry about forgetting to open it and burning the impeller." Don't you look over the stern after the motor starts too see if water if spiting out the exhaust? I do. No water :banghead:Darn, I forgot the raw water valve.....
I shut off every seacock when leaving the boat. (I was on submarines so am a little anal about sinking) To me its just good marine practice. If you are in fresh water or water that can freeze its a must. I've seen more than one boat on a lake sunk at the dock when an inboard line froze when a quick cold snap has hit, even if the lake isn't frozen. I am in salt/brackish water but still close the seacocks - why take a chance? If you are worried about forgetting to open the engine seacock, do what I do, leave the engine key hung around the seacock lever. That way I can't start the engine without accessing the seacock. Leave seacocks below the waterline open and its easy for you but a hose failure will sink your boat. Your boat, your call.
 

kito

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Sep 13, 2012
2,011
1979 Hunter Cherubini 30 Clemmons
If you are always going to leave your seacocks open then why do they have those little shutoff handles ;) I plan on making a red laminated check off list mounted to the bulkhead where I can't help to not see it. I like the idea of the engine keys on the intake valve but as anal as I am, I take the keys with me when I leave. I learned a lesson from an old dockmate. He left his keys in his cabin. Some kids broke in and took his boat for a joy ride. They found his boat all tore up stuck on a rock wing dam.
 
Feb 26, 2004
22,759
Catalina 34 224 Maple Bay, BC, Canada
I've had my boat for 18 years. Only ONCE have I forgotten, and only because I was taking someone out for ride and for some stupid reason we were in a hurry. Figured it out a few minutes down the line and opened it, the same impeller stayed there for the next few years.

Guys, I've been meaning to say this for years: this isn't rocket science!

When you get in your car you have to have the key to start it. Same with your house, and then you have to start turning on lights if it's nighttime. There are a LOT more complicated things to do in simply running a sailboat under sail, that I can't for the life of me figure out why this is such a recurring issue/topic.

Open hatch. Go below. Open seacock(s). Turn battery switch on. Start engine.

Four things? And you can't remember? :solame:

If you think you need it, sure, then post a checklist. I wrote one years ago and we've used it once, only to make sure it was right.

You could also simplify this by placing a note on your electrical switch: open seacock. 'Cuz ya can't start the darned engine without turning on the power.

I also agree with Kito that leaving the ignition key on the boat is a bad idea. We have all our keys (dock gate fob, ignition key, hatch and boat locker key) on our floaters, so I never separate them.

Your boat, your choice. :)
 
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kito

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Sep 13, 2012
2,011
1979 Hunter Cherubini 30 Clemmons
I got to admit, in my 40 years of boating........I have forgotten the ol' drain plug when launching my ski boat more than once! LOL
 
Mar 20, 2014
12
hunter 28 Tyler
Those floaty's will only float a few keys ! have you ever tested one ,I have after a friend was bragging about his new floaty and tossed it in and it sank
 
Mar 20, 2014
12
hunter 28 Tyler
The next day at the marina when I walked up he had his dive gear on and was about to go down to get the keys and his wife was describing the keys to him ,he looked at her and said "OK Joyce I will look through all those keys down there and will not come up without that set" Ha Ha!
 
Jul 7, 2010
30
Hunter 31 Deale
I agree with this person's instructor. It takes maybe 2 minutes to raise the cushion and left up the board and take a peek at the rear transmission, sea cock, and shaft seal. Call me cautious, put as an ex-pilot I would not dream of taking off with a thorough pre-flight; I treat the boat with the same respect.

In an emergency, it is a simple matter to pull back the cushion and remove the board. I am careful not to turn the aft compartment into a storage locker with the danger of burying the access under a ton of crap.