Replacing broken Gate Valve - help pls!

[Turnbuckle]

Gate Valve drain from galley sink stuck firmly closed (please see attached image).

The red tap turns without moving the gate, so I suspect the spindle has sheared. The through-hull is about six inches above the waterline, and the boat is currently in the water, but in a Marina on a calm day it should in theory be possible to remove the gate vale from the through hull fitting and replace it without too much worry about flooding and without a costly lift-out.

But how to get it off without damaging the through-hull or unseating the very old seal? It's probably been there for the past 40 years. And it's 3/4 inch (or so it says on the casting).

I can do a proper job and replace the whole lot over winter, but I really don't want to lift out now. Does anyone have any tips or hints please?

 

[mrangry]

I am no plumber but can you not just remove the nut under the gland and lift out the spindle and just replace that?

 

[penberth3]

I am no plumber but can you not just remove the nut under the gland and lift out the spindle and just replace that?

Yes, the valve head with all the moving parts should unscrew from the body. Then find out what's happened inside. First I'd check it isn't the red handwheel turning on the valve stem - the square hole can get rounded.

Before you do anything, make sure you have some tapered wooden plugs!

 

[James_Calvert]

It is just as likely that the threads in the gate have stripped, as the spindle has snapped. In which case it will be jammed in.

Also whilst the end fittings will be a standard size, the internals won't. So you can't replace one spindle with another.

To answer the question, you need to stop the threaded part of the skin fitting rotating. If you can get some mole grips onto this, you stand a chance. But when I did this job high and dry in the yard, the skin fitting started to move, so had had to take this out and reseal it.

Good luck!

Might be an idea to ram in some kind of bung into the skin fitting from the outside...

 

[Boathook]

Are you able to heel the boat over so the fitting is above the water? You could then have a go at seeing whether the valve will undo. Either way I would purchase a new skin fitting and valve plus sealant ready for the job. If there is room I would fit the Trudesign fittings as the are all 'plastic.

 

[VicS]

If you do want to replace the valve ( with a ball valve perhaps) you will need a means for someone to counter hold the skin fitting from outside while you remove the old and fit the new one inside.

The tool for the job is a "step wrench" but a piece of flat bar the just fits the bore and an adjustable spanner should do the trick ... hopefully there are some little lugs inside for something to engage with.

Dn't bugger the thread on the skin fitting with mole grips or the cowboy plumber's universal tool, water pump pliers ,or you will have to cut it off if you later want to remove it

 

[greeny]

Are you able to heel the boat over so the fitting is above the water? You could then have a go at seeing whether the valve will undo. Either way I would purchase a new skin fitting and valve plus sealant ready for the job. If there is room I would fit the Trudesign fittings as the are all 'plastic.

Post 1
The through-hull is about six inches above the waterline,

 

[greeny]

Do what Vic says.

 

[Boathook]

Post 1
The through-hull is about six inches above the waterline,

Misread the post! Above the water line have all the bits and replace. If worried about water ingress still heel the boat over a bit.

 

[peter gibbs]

I am no plumber but can you not just remove the nut under the gland and lift out the spindle and just replace that?

You will be very well advised not to take any action that could unseat the skin fitting. After so much time you could well end up with a leaky fixture and no effective means of removing it whilst afloat. Fitting an entirely new one, should you be able to remove the old, would require the outer flange to be held stable whilst the securing nut is tightened on board - not an easy task - I've done it, but only on land.

If you can remove the guts of the valve and have it open, that would be a good solution. The, if you are unhappy to have a permanently open valve you could pop in a tap fixture inboard of the valve. A simple plumbing valve would do fine.

Gate valves are an apparently secure closure but hell when they go wrong. Be sure to use a ball valve in future.

PWG

 

[sailaboutvic]

As Vic's said is your best option , but the worst come to bit you , you said your I. The marina and the fitting is 6" above the water line , there very little chance of any water getting in on a flat day , 6" is another to grind off the end of the fitting with a batteries grinder and fit a new hull fitting .
If your that worried use a toilet plunger on the out side while doing the job .

 

[Turnbuckle]

I am no plumber but can you not just remove the nut under the gland and lift out the spindle and just replace that?

Er not really. I need to repace the valve. I need hints or tips about freeing up the joints without disturbing the seal on the through hull.

 

[Turnbuckle]

Thanks for all the advice. At least it's jammed 'closed', not 'open'. I'm tempted to leave it until the winter haulout and wash up in a bucket!

 

[Graham376]

If you're in tidal waters, why not dry out alongside wall or posts? If access inside is good, should be easy to fix between tides even if skin fitting needs changing.

 

[john_morris_uk]

6" above the waterline and you're not going to sink. Just choose a flat day and be prepared to replace the lot. A new hull fitting and DZR ball valve is not that expensive and you'll know the whole job has been done properly. Gate valves have no place on a boat IMHO as they are often brass inside and don't give any signs of failure. The chances of removing the old valve (or it's internals) without disturbing the seal of the through hull are slim IMHO. If you're anxious about it being close to the waterline, heel the boat a bit (it'll make it easier to get at too.). I usually remove fittings by using a hole saw. I hammer a bit of wood in the middle to locate the pilot drill in the hole saw arbour.

 

[Stemar]

6" above the waterline and you're not going to sink. Just choose a flat day and be prepared to replace the lot. A new hull fitting and DZR ball valve is not that expensive and you'll know the whole job has been done properly.

Yep. Even if you had to leave the boat without a skin fitting, a cover sealed to the hull with a bit of goop would be fine for a couple of days. I'd be a bit more thorough sealing it on a mooring, but in a marina I can't see a problem.

Also, consider a Marelon or similar fitting.