New owner sea cock question

Oct 23, 2019
2
Catalina 310 Hampton VA
Greetings. I have just taken ownership of a 2005 310 and wondered what the consensus was on keeping sea cocks closed when not in use. I currently have the macerator and head cocks open and prior owner closed all when in port. My shower sump is not currently draining and was also wondering if that had something to do with it. Much appreciation for any help!
 
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Dec 16, 2011
240
Catalina 310 Atlantic Highlands
Because I'm only on my boat every 7 days, I keep all my seacocks closed. I have a sign I put on the Nav station that announces "WARNING SEACOCKS CLOSED" to remind me every time I get onto the boat to open the seacocks. We do get a lot of growth and critters in our harbor, and sometimes I've had stuff between the ball and the hull opening that blocks the drain or slows down the drain. I solved this situation by having my bottom cleaned every 3 weeks and the diver takes care of making sure all the through-hulls are clear.

One thing to check with regards to the shower not draining. The shower drain (at least on hull #48) is on a Y-valve with the fridge drain. So you may have that Y-valve set to the fridge and not the shower...that might be why it is not draining.
 
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Oct 22, 2014
16,137
CAL 35 Cruiser moored EVERETT WA
@SawyerCurt speaks the truth. An inspection of your boat by USCG would go poorly if you had the Macerator seacock open.

Welcome Brian (@Bryan D ) Congrats on your new boat. You chose wisely. Have fun sailing the lower Chesapeake. I is wonderful water to sail.
 
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Nov 18, 2010
2,441
Catalina 310 Hingham, MA
we liveaboard full time. The engine and sinks seacocks are always open but we exercise them once a month. Our head intake is connected to the head sink drain. The old head intake was repurposed to the watermaker. The other seacocks get closed after each use. Those are watermaker, macerator and shower sump/refer drain.

If the shower sump isn't draining the first thing to check is the seacock, it's under the galley sink or under the head sink (they changed somethings around during the years). I believe the pump is located under the head sink on your boat. Hit the button in the shower once you are sure the seacock is open. Does the pump turn on? If it does but the sump still doesn't drain, the next think to check is the Y valve. It selects either the shower sump or refer drain. Before changing it, listen to the refer with the door open, do you hear sucking? If it's not the Y valve the next thing to check is the screen next to the pump, it could be clogged.

good luck
 
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Jun 21, 2004
1,884
Beneteau 343 Slidell, LA
Keep seacocks closed when not on board. Open & close them periodically to keep them operable. If you have an onboard air conditioner system onboard, close the AC pump seacock before sailing ;otherwise, the cooling water pump for the AC will lose its prime and you will have to deal with that aggravation. Curt’s advice is right on with regards to overboard discharge; there is typically a “Y” valve that diverts discharge into the holding tank or overboard; it must be padlocked or zip tied in the closed position where waste is directed to the tank. You will incur a hefty fine if USCG inspects and finds that it isn’t physically locked out. It’s a good idea to have a written statement onboard as to how discharge is managed.
 
Nov 18, 2010
2,441
Catalina 310 Hingham, MA
Keep seacocks closed when not on board. Open & close them periodically to keep them operable. If you have an onboard air conditioner system onboard, close the AC pump seacock before sailing ;otherwise, the cooling water pump for the AC will lose its prime and you will have to deal with that aggravation. Curt’s advice is right on with regards to overboard discharge; there is typically a “Y” valve that diverts discharge into the holding tank or overboard; it must be padlocked or zip tied in the closed position where waste is directed to the tank. You will incur a hefty fine if USCG inspects and finds that it isn’t physically locked out. It’s a good idea to have a written statement onboard as to how discharge is managed.
Curt was not talking about a blackwater discharge y valve. Most of the 310s only have holding tank and macerator setup, no direct discharge.

The Y valve is for selection of the shower sump or refer drain.

sorry, don't want the OP to be confused.
 
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Jul 27, 2011
4,530
Bavaria 38E Alamitos Bay
So, the question about keeping the sea cocks closed when off the boat, or at other times when not being used, usually has to do with the condition of the attached hoses. Boats have sank, or nearly so, after a hose leaked, broke, or come off a sea cock that had been left open. That could happen if a hose clamp rusted through and sprang off, then some time later the hose worked off, etc. Thus, the insurance requirement for double hose clamps at sea cocks. The doubles might help you get by a lost hose clamp for a while, but one has to notice at some point that a clamp has come off or risk losing the other one as well. So, CHECK your hose clamps and the integrity of the hoses at the barb. The best way to check ‘em is to take ‘em off and closely inspect.

Opening and closing the sea cocks routinely insures that they will operate as required. I normally keep mine closed when away from the boat (out of town) or off the boat for extended period. The ones I rarely need are closed for long periods, etc. The diesel intake is usually open, however, b/c it’s a PIA to close and open as it is a strangely configured needle valve that's hard to reach and operate. (It’s a component of a Yanmar saildrive).

But there’s more. The sea cocks themselves can degrade/deteriorate, leak, break, or become frozen or stuck. So, they should be routinely inspected, and even replaced every couple of decades, etc. If you have a sea cock that does not operate, it should be replaced. I’ve replaced 9 of the 13 (ridiculous number) on my 1999 Bavaria. Three that were swapped out could not be closed b/c the attachment between the handle and the ball had rusted through, or the handle rusted off I could not find a replacement. One down-side of owning a metric boat in the States.
 
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Jun 21, 2004
1,884
Beneteau 343 Slidell, LA
JK, thanks for the clarification. My current boat & previous Hunter were configured differently than your Catalina; however, neither boat had a macerator.
 

JRT

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Feb 14, 2017
1,970
Catalina 310 211 Lake Guntersville, AL
Congrats @Bryan D , we are new owners this year also and love the 310 upgrade.
I keep mine closed and open when we arrive just because I don't want any surprises. I also like the routine of openning and closing them since we don't get to sail weekly.

Concerning discharge of holding tank valve, my switch is zip tied at the breaker panel, but I see nothing on the valve? It is closed of course and I have exercised it a couple of times to make sure it is still functional. Any pics of our valve ziptied closed would be helpful.
 
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KZW

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May 17, 2014
829
Catalina 310 #307 Bluewater Bay, FL
I have C-310, Sail #307, built in 2005.
To drain the shower:
1. Rotate the Y-valve under the head sink fully counter-clockwise (about 1/2 turn), so the two Y-arms point outboard.
2. Open the smaller seacock, located behind the panel in the head (just outboard of the larger macerator seacock).
3. On the power panel, turn on the shower drain
4. Push the switch above the head to turn on the pump. You will hear the tone of the pump change when the water reaches the pump, and when there is no longer any water going through the pump.

Note: earlier boats had slightly different plumbing. The diagram in the manual that came with my boat is incorrect - it reflects an earlier plumbing fit.

To drain any water in the refrigerator, follow the above steps, but rotate the Y valve fully clockwise (two Y-arms facing inboard). It takes several seconds for the suction to pull the water from the refrigerator on the starboard side, through the pipe to the pump on the port side and out through the seacock. Note: That same seacock is used to intake seawater to flush the head. I strongly recommend you re-plumb to use freshwater flush. There is a thread on how to do that on this site.

My boat is at a dock and sailed maybe once a week - year round. The heat exchanger seacock is kept open while engine is running, or when sailing - in case the engine is needed quickly. The air-conditioning seacock is kept open in the summer when the A/C is running to keep the interior boat temperature down to 85 degrees. Otherwise seacocks are kept closed unless in use.

Each month cycle all seacocks 5 to 6 times. This is to ensure they are free to rotate when needed. Regarding the Y-valve: I leave it in the refrigerator position on even months and shower position on odd months. If you leave it in the same position all the time, the rubber disk inside can take a set, preventing the valve from rotating (don't ask how I know this). I dive on the boat monthly to clean the prop, hull, and ensure the through-hulls are clear. It is amazing how fast barnacles grow. When your bottom is painted, ensure the through-hulls are painted all the way up to the rotating ball on the seacock.
 
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KZW

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May 17, 2014
829
Catalina 310 #307 Bluewater Bay, FL
Thank you to all with the great intel. I am coming from a C & C 25 that doesn't have all of this fancy stuff! Love the handling of this boat and look forward to gaining more of an understanding of the features
Send me a PM if you would like a copy of the diagram I made on where everything is located in my boat.
 
Oct 13, 2020
2
catalina 310 sodus point new york
Send me a PM if you would like a copy of the diagram I made on where everything is located in my boat.
KAZ please send me a copy of the diagram, I am unable to find the shut off for the head intake, our head will fill up when we are not on the boat.
 

KZW

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May 17, 2014
829
Catalina 310 #307 Bluewater Bay, FL
The sea water intake seacock is located behind the panel in the head/shower wall. Enter head, turn 90 degrees left, look down at the wall and there is an access panel. The large seacock to starboard is the holding tank discharge. The smaller seacock to port is the sea water entry for the head. That same seacock also is the exit to empty the shower and water from the refrigerator when you defrost it. The shower/refrigerator Y valve is under the sink in the head, attached to the forward wall

stand by for the diagram
 

KZW

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May 17, 2014
829
Catalina 310 #307 Bluewater Bay, FL
The attached PDF diagrams show where things are located in my C-310, built in 2005, sail no 307. Your boat may have some differences.
 

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Oct 13, 2020
2
catalina 310 sodus point new york
The attached PDF diagrams show where things are located in my C-310, built in 2005, sail no 307. Your boat may have some differences.
Thank you! that is the same design 2004 #267 (Minus the Microwave). I believe I have it closed but I am still getting water intake on both dry and wet pump. the bowl will fill up if not watched. I am baffled, i believe it will be need to be replaced. Do you have automatic fire extinguishers?
 

KZW

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May 17, 2014
829
Catalina 310 #307 Bluewater Bay, FL
I apologize in advance if I’m teaching you to suck eggs. The handle for the seacock should be horizontal in the closed position, and vertical in the open position. You should cycle each seacock five or six times each month, otherwise they can stiffen and be a real bear to open/close. Take them apart and lubricate them (I use Teflon grease) when you haul the boat. They seacock for the kitchen sink seacock is a real “joy” to access.

Is it possible something like a barnacle is jamming the seacock open a bit? Theory says you can take it apart with the boat in the water, using the white on the seacock to plug the hole. I’m not inclined to do that on my boat