Narrow body ball valve

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roaringgirl

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Half way around: Wellington, NZ.
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Due to corrosion, I had to cut the old ball valve to pieces to get it off the bottom of the holding tank. The position of the tank means that although it's a normal 38mm/1.5" fitting, the ball valve itself can't have a diameter much larger than the outer diameter of the threaded sections. Does anyone know where I can get hold of a narrow-body ball valve?
 
Don't know if it helps, but you could safely go down to a 1 - 1/4" ball valve. This will leave you with an ID of 32mm, which is about the same as the ID of hose pipe intended for 38mm hose.

Correction: Meant to say 'ID of a hose tail intended for 38mm hose'.
 
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Do you need to put it right under the tank? Can you come off with hose then place the valve in the hose away from the tank. If you use clear hose you can see if it is blocked (this is often a blockage point) then squeeze the pipe with a clamp & 2 bits of wood. Remove the valve without draining the tank. Unblock the valve & rod through to the hull sea cock & Bob's your uncle.
 
Have never seen a valve of the type you are looking for. Logically you cannot have a body the same diameter as the threaded section as there will not be enough room inside it for the ball valve. What happens after the valve? Does the hose go straight to the seacock? If so there is no need for an isolating valve from the tank.
 
roaringgirl said:
Yes, it's called a 'reduced flow' valve
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Google the term and you will find several suppliers of such valves in all the regular sizes including 1 1/2 BSP.

Do you really need an isolation valve there? Reducing the diameter in such a location is not a good idea as that is one of the areas most prone to blockages.
 
Don't know why you are having difficulty as the sources are on the first page when I googled "reduced flow ball valves" Anyway they are ITAP products made in Italy and are nickel plated brass. They are not intended for marine applications (cannot imagine why one would want one on a boat except in poorly designed locations like yours) as they are usually used for balancing flows in domestic water circuits. One UK source is www.pcmengbelfast.com but I expect you could order them from a decent plumbers merchant.

Provided you use a DZR skin fitting and tail don't think you will have a corrosion problem with the valve in a holding tank outlet with them as the bodies are not exposed to any seawater in normal use.
 
Hi roaringgirl, can you post pics of the old ballvalve and the mounting position? What size was the old ballvalve? I wouldn't want to drop the valve aperture at this point if you can avoid it as this will be the point where blockages will occur.
 
philwebb said:
Hi roaringgirl, can you post pics of the old ballvalve and the mounting position? What size was the old ballvalve? I wouldn't want to drop the valve aperture at this point if you can avoid it as this will be the point where blockages will occur.
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See post#9.

roaringgirl has already been advised of the problems of blockages and even the necessity of having a valve at all. although that depends on what happens downstream of the current valve.
 
Have ordered some clear nylon reinforced hose to run between holding tank and thru-hull, will place the ball valve half way along it. Doing it this way negates the need for the reduced flow for clearance. I do need a ball valve between tank and hull as it allows me to have an optional bypass for the holding tank so that when the inevitable blockage occurs during heavy weather on a multi-day passage I don't have to spend seasick hours below deck dismantling parts covered in sh*te while my 3 year old keeps watch!
 
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roaringgirl said:
Have ordered some clear nylon reinforced hose to run between holding tank and thru-hull, will place the ball valve half way along it. Doing it this way negates the need for the reduced flow for clearance. I do need a ball valve between tank and hull as it allows me to have an optional bypass for the holding tank so that when the inevitable blockage occurs during heavy weather on a multi-day passage I don't have to spend seasick hours below deck dismantling parts covered in sh*te while my 3 year old keeps watch!
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Please don't use reinforced hose for any sanitary runs - use the correct sanitary grade hose. Presumably you have a Y valve already if you can use the loo without the output going through the tank. In that case you do not need an additional valve. Do you have a separate outlet for the holding tank? If you have a gravity tank where everything goes through it then the seacock is the isolating valve.

Reason for asking these questions is that I am struggling to understand why you want this valve at all - maybe I am being a bit thick. A diagram of the plumbing would help.
 
Tranona said:
Please don't use reinforced hose for any sanitary runs - .
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Why not? (I assume you are referring to reinforced clear nylon pipe not wired pipe)I have had a short length ( 700mm) at the point where blockages have occurred in the past & fitted it about 2.5 years ago & it has helped me isolate blockages & clear the pipe just as I described in my earlier post. There has been no sign of it disintegrating & I have checked it. It is much easier to bend & get out of a short run than a wired pipe which , due to its rigidity, is a pain to dismantle. The rest of my piping is unwired sanitary hose so any leaking smells has not been evident, but one cannot see into it. However, my heads do not smell as I use the boat full time all season ( assuming that might be behind your reasoning)
 
roaringgirl said:
Have ordered some clear nylon reinforced hose to run between holding tank and thru-hull, will place the ball valve half way along it. Doing it this way negates the need for the reduced flow for clearance. I do need a ball valve between tank and hull as it allows me to have an optional bypass for the holding tank so that when the inevitable blockage occurs during heavy weather on a multi-day passage I don't have to spend seasick hours below deck dismantling parts covered in sh*te while my 3 year old keeps watch!
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That sound like a good plan. Despite what some will say, the use of sanitary hose is not essential. Only some people have smell problems and find that sanitary hose cures the smell. Many others use standard pvc hose without a problem.

Www.solocoastalsailing.co.uk
 
roaringgirl said:
It's ok, I've got a workable plan :)

Sticking with the
see-through pipework because holding tank is stainless with no gauge. Very hard to diagnose blockages.
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Mounting a bass valve to a stainless steel tank is not a good idea anyway. The valve becomes anode to the tank and will corrode quickly because of the large cathode surface (ss tank). If your tank outlet pipe is treaded, do not fit a brass hose tail. I suggest using ss or composite.
 
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