Screw down ball valves completely?

[Tim Good]

See photo below. I am replacing the old bronze valves with stainless ones as they fit onto a big stainless mixing pot + the bronze ones are 20 years only.

You'll see the handles of the old ones are all aligned. However if I screw down my new stainless ones entirely they don't align and the handles are impossible to close. Two questions:

1. Do I need to screw them all the way down? They are protected by a single large 2" ball valve which is the main seacock.

2. Does it matter which around way ball valves are installed? Assume not but thought I'd ask.

 

[Kelpie]

I used PTFE tape to help bind the threads and lock the new valve in place in such a position that it could be easily operated. Takes a fair bit of trial and error.
There should be an arrow on the valve indicating which way round it should be fitted, but that probably doesn't matter much when installed on a boat.

 

[PCUK]

I use Sikaflex on the threads, tighten the fittings as far as they will go then back them off to the required position. Once cured there is no movement although they can be undone with big spanners when needed. 100% reliable and water-tight. You can also fit locking nuts as 'belt and braces'.

 

[ghostlymoron]

I've always used PTFE tape for this its much easier to dismantle in future if you need to, clean and economic. If you put four turns on that will provide enough adjustment and not leak. Alternatively, you could use a backnut and lock against it. (Still use tape though). I think you can get liquid PTFE but I've never tried it.

 

[macd]

I think you can get liquid PTFE but I've never tried it.

I use the stuff from time to time: very convenient and a good seal. However, it's not that easy to undo: OK on smaller fittings with good access, but in the typical tangle of hoses etc under a sink, not so easy. A blast from a blow-torch is reputed to help (as it does with thread-lock compounds) but I've not tried it.

 

[Giblets]

Rather than PTFE tape may I suggest Locktite 55 PTFE cord. Can be backed off if required (which tape can't be) and can be built up on thread to finally position fitting in desired position. Can be used for most applications.

http://www.loctite55.co.uk/

No connection other than a professional user for many years.

 

[Tranona]

You could use a lock nut on the spigots to get the handles to line up if there is room. The seal is on the threads so not essential they bottom.

 

[jakeroyd]

I came across a similar issue replacing one of my seacocks.
It is effectively in a little cupboard so access very limited.
In order to get the hadle where i wanted it I , like others above , sealed the threads with Sikaflex 291.
The threads were not bottomed and it's very difficult to know how tight they are even if they are bottomed.

However , once the hose had been fitted the assembly can not unscrew , so I convinced myself all would be well.
The comments above leave my mind a little more settled.

The 'cupboard' is so small I have since had to make myself a 'nut turner' made out of plate to finally tighten the retaining nut for the skin fitting up.
I will have to tap this round to get the nut tight.

 

[Tim Good]

I came across a similar issue replacing one of my seacocks.

I thought for skin fittings you put the skin fitting through and thighten the valve to maximum, then position the handle where you want it, then tighten the retaining nut to bed down onto the backing plate and sikaflex?

 

[ghostlymoron]

That only works if you are replacing or removing the skin fitting. The OPs situation is fitting new valves on some kind of manifold.

 

[Tim Good]

That only works if you are replacing or removing the skin fitting. The OPs situation is fitting new valves on some kind of manifold.

Well both actually

I have 3 skin fittings to grind off tonight and re install with new. Then 6 valves to put on the manifold.

 

[rob2]

We've all probably done all the above to suit the situation. As I understand it, the ideal is to have backing nuts under the valves so you screw them down to the desired position and then screw up the nut to lock in position. This doesn't preclude the use of Loctite or PTFE to ensure a waterproof joint.

Rob

 

[Tim Good]

Whole new set of stainless valves aligned and installed with ptfe. Mecri for the advice on this one.

 

[macd]

Whole new set of stainless valves aligned and installed with ptfe. Mecri for the advice on this one.

Well, that looks a treat, mecri

 

[Giblets]

I hope that's not a black iron M&F elbow top left!!!

 

[Tim Good]

I hope that's not a black iron M&F elbow top left!!!

Male to Female? Yes.

Black Iron?

 

[Norman_E]

One issue not addressed is whether ball valves should be fitted in a particular direction. It may not matter but ball valve bodies are made in two halves. The main body contains the spindle and ball and the cap screws into the main body. I have always thought that the pressurised end should be the main body, and the cap should be on the other end. In the case of seacocks that means body to the skin fitting and cap to the tail. On that basis the ones on the right in the photo look the wrong way round. My reasoning is based on the only one that I have seen broken in use. It happened on my boat and the break occurred immediately above the ball at the end of the screw threads where the tail screwed into the body, the tail broke away with a piece of the body, leaving the ball exposed. The ball was retained by the spindle and did not pop out.

Does anyone have any alternative view?

 

[Boathook]

You could use a lock nut on the spigots to get the handles to line up if there is room. The seal is on the threads so not essential they bottom.

I've used a back nut before to lock a fitting in position. PTFE tape on the thread. Can be fiddly but does valve to be set at correct position for use. Also, most ball valves seem to have an arrow indicating 'flow' which on a boat I think should be indicating water in from a skin fitting rather than outlet fromm a sink, etc.

 

[Tim Good]

It happened on my boat and the break occurred immediately above the ball at the end of the screw threads where the tail screwed into the body, the tail broke away with a piece of the body, leaving the ball exposed. The ball was retained by the spindle and did not pop out.

Does anyone have any alternative view?

Yeah i did consider this but couldnt find any thing to suggest otherwise. As you can see on one side I've done it differently but that was to avoid cutting the handles down as they'd face the other way. Also I like things to be symmetrical and having one side with up facing handles and the other down would make for bad Feng Sui

So this actually happened on a boat to you or in an industrial application? I suppose in my case it is less important as there is a main seacock feeding them that can be closed in the case of an emergency. When off the boat I close it.

 

[Norman_E]

Yes it was on my boat. A 3/4 inch ball valve that let water in for the fridge compressor cooling circuit. The boat had to be lifted to replace it.

On your setup with a main seacock controlling everything I doubt it matters which way you put them. I have seen some with a direction arrow on them though most do not have one.