How does this sea cock work

DAKA

DAKA

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Has anyone got a sea cock like this please ? (big odd shaped one in the front)

Can it be turned off ?

ac9d22762d5006cb14235c75a65e2ca5.jpg


Pipe from the top goes to the holding tank. *

Pipe to the right comes from the head. *

Lever to the right sends black waste straight from the head to sea.

Lever up sends black waste from the head to the holding tank.

Result it can not be turned off ??????????

Either to sea or to holding tank but not off ?????

If I put it at 45' between the two positions the head will not pump but I am not sure if that is off ??

Anyone help please ?

I need to change the loo pump next time I go to the boat and really need to know how it works.














* could be the other way round ?

Yes I know they were dirty, photo taken just before wire brush and greased /forums/images/graemlins/smile.gif
 
It's a diverter valve rather than a seacock, therefore it only closes off one of the two outlet ports at a time, and never the toilet inlet port.

Therefore in that respect your assumption is correct and it cannot be shut off.

I suppose the nearest you will get is turning the lever to holding tank outlet which at least isolates it from the sea.

I have to confess that I have never seen a diverter connected straight out like that, my last two boats have always had a seacock after the diverter.

Hope this helps.

Neil
 
as long as the sea cock is closed, the other valve must be able to be turned off too, if you look at pic, there is an option for a 3rd pipe off it so if it will turn round to that side so it would be from closed , no pipe bit to the outlet it should seal the pipes from the boat closed.
 
Stirrer /forums/images/graemlins/laugh.gif

Daka
Does the lever hit a solid stop in each position or is it possible it might move through 180 to the opposite position it's in now ?
Just guessing as I'm not a bog plumber /forums/images/graemlins/blush.gif
 
Hi Pete looking at photo the leaver will turn through 270 degrees usually the handle normally points to the direction of flow so if turned so the handle is opposite to the horizontal pipe the valve should be closed hope this helps if not have some buckets handy. /forums/images/graemlins/laugh.gif
 
I very nearly did post it in PBO, but then I thought as it is on a Princess there would be better chance of someone having a similar one on here .



I may post it there if no success here but I have always been amazed at the quality of response here /forums/images/graemlins/smile.gif

It was a bit of a gamble really /forums/images/graemlins/wink.gif
 
I take it you want to block both seawater and the holding tank contents at the same time from flowing back into the toilet whilst you work on the pump? Don't see how you can do that as if you turn the lever to 45deg, it will be partially open to both sides IMHO. This seems like an odd installation to me. On boats I've had, the toilet discharge goes to a Y valve which gives you the choice of discharging into the holding tank or to sea through a seacock so if you choose discharge to the sea and shut the seacock, the toilet is shut off from both the holding tank and the sea.
In your case, I guess your only choice is to leave the seacock in the holding tank position assuming that the toilet pump is above the level of the holding tank. Completely emptying the holding tank will help of course
 
Yeah...Yeah...

Princess??????
Bit of royalty /forums/images/graemlins/laugh.gif /forums/images/graemlins/laugh.gif

I bet thier bogs dont have the same system /forums/images/graemlins/smirk.gif /forums/images/graemlins/smirk.gif
 
The lever can't physically go through 270deg, only 180deg and I can't see how 2 of the pipes could be blocked at the same time given that it's primary function is to close off only one pipe at any one time
 
I'm afraid I don't grasp the full meaning of this sentence but it doesn't sound al to good to me. Is there a problem with this engine or so?

**************************************************

Can you move the handle 180 degrees from shown....It would be Off then...It has a 90 degree port in the rotor.
 
Imagine the centre of the valve as a circle with a gate inside that covering approx 33% of the circles circumference. In the position shown in the picture the gate is covering the outlet port to the holding tank.

As you move the lever upwards (anti clockwise) the gate moves anti clockwise to cover the port to the sea outlet, and consequently open the holding tank outlet.

Because of this you cannot shut off the toilet, but as said before best to have it switched to holding tank before doing any work on the loo.

Clear as mud?? or maybe something else in this instance.

Neil
 
Thanks for everyones* prompt reply , the holding tank is brand new and empty but I would have preferred it to be shut off during the operation and it is about time I learnt how to use it. /forums/images/graemlins/smile.gif

It does look from the photo that it will carry on past 90' so it could turn all the way round 180', I do remember it does go slightly past 90', I thought it was getting worn and didnt try to push it deliberately past 90'



I will try it next time I am on the boat /forums/images/graemlins/smile.gif
Sounds a good plan.
Thanks again
cheers
Pete /forums/images/graemlins/smirk.gif


* told you so Doug , PBO is the right place for how to open and get the last drop out of a paint tin but technical stuff here /forums/images/graemlins/tongue.gif




Hi Ian,

we are going for a Gallop on the beach on Sunday, do you want me to try to find a spirited stallion for you ?
Tides out, suns out, offshore breeze........perfect /forums/images/graemlins/cool.gif
 
I am struggling Neil,

I am thinking of it as a T tap which I once had to switch from port/starboard tanks to one engine.


If I look at it as a T tap on its side I think it may be possible to shut it off if the lever does go 180'

I cant think for what other reason it would be made to go past 90'

I can try it and find out, I will be careful when taking pipes off and have wedges on standby.
 
IMHO its an outlet cock only, the one forward of this one is the inlet to the toilet as it looks like half or three quarter inch bsp hose, the big vlve is set to either exit waste direct from the toilet or from the holding tank, maybe im wrong but I dont think you would want water flowing in to the toilet through the same outlet waste goes through, ive worked on many 360s and not seen that cock before. Looking at the stops on the red handle and top stop on valve body it rotates through 180 only so is only a 2 position valve to exit only from either pipe.
 
3 port valves normally come in 2 types what is called "L" type or "T" type

The "L" type allow centre port connected to either end port plus off. The "T" type have 4 positions end 1 to centre . enf 2 to centre, all connected or all closed.

Normally the closed position is with the handle pointing away from all ports ( 180 degrees from the position in your pis) and when the handle is pointing to ope of the ports it is connected to the common (centre) port or in the case of the 4 position when pointing to the centre this is the all ports open position

details here and here and here
 
Thankyou Roger /forums/images/graemlins/smile.gif

The L shaped 365N makes perfect sense, thanks /forums/images/graemlins/smile.gif
 
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