Weeping seacock

bumblefish

bumblefish

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At long last I got my old girl back in the water today, 09:30, however, at the last moment I re-checked the raw water seacock, decided I was not totally happy and so I replaced it quickly! I put a new 3/4'' seacock on and after launching, before release of the straps, I was happy, now I have a very slight weep on that fitting, the only one of the many I re-bedded and/or changed. I know the stern gear is meant to drip at 1-3 per minute and this is much less than that, enough to just wet a piece of tissue 1cm or so after 5 hours, should I be concerned, try tightening the fitting a little or ignore it until next time out?
 
Are you sure where the water is coming from? Is it from the seacock thru hull seal/sealant or is the leak from the hose connection upstream of the valve which is easier to fix and doesn't need the boat out of the water. What kind of seacock did you use and is there a backing pad (best practice) on the inside of the hull under the seacock nut or does it tighten straight onto the hull? What sealant did you use and did it have time to cure before launching?

Leaks seldom get better. It is strange for the newly fitted seacock to leak if it was installed with plenty of sealant and of the right type, especially as you apparently launched soon after fitting it. Tightening gently might help but then maybe it was overtightened initially and squeezed the sealant out before it cured, some types suggest initial slight tightening, then leave 24hrs before tightening fully.
 
Sorry, I should have said the leak is probably from the junction of the through hull fitting and the ball valve. the skin fitting is fine.
 
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Sorry, I should have said the leak is probably from the junction of the through hull fitting and the ball valve. the skin fitting is fine.

[/ QUOTE ]

OK so the next question is did you use PTFE tape on the threads before assembling the valve to the thu hull? If you did it might help to very gently tighten the join just a little more. Otherwise there are some options other than a lift/hold in slings, like drying against a quay just enough for the water level to drop below seacock depth whilst you redo the join. You could perhaps consider tapping a softwood plug into the thru hull from the outside (before the water temp drops too much!) and then redoing the join.

If it was me I wouldn't want to leave it. I might try tightening gently if it were taped but realistically I would be looking either at lift/hold in slings for an hour or finding a convenient quay/drying posts and working out the tides to give me time enough to do it, you don't need to dry out completely. Warning however, the skin fitting may try to turn as you unscrew the seacock and you may need a helper outside to prevent this, not so easy if this is from a dinghy! The Liz BTW will dry against a wall quite well, my old one is even pictured on Lymington postcards, dried against the Quay for antifouling one year.
 
Thank you for that advice, I did put several turns of PTFE on the join so I might just try a gentle tightening. I also considered bunging up from outside, however it is the raw water intake and has a rough filter on the outside! I am not sure where the nearest wall is to Brighton as apparently we have been told that the platform inside the marina is not useable, too dangerous as it can get slippery?
 
Shame about the grill over the intake! So if a gentle tightening doesn't work I would speak nicely to Brighton Marina about a lift and hold in slings perhaps over their lunch hour but I suspect it will still be costly.
 
I have been down there so much lately that I am probably on the pay roll! At the weekend one of the lock gate chaps certainly confused me with the yard staff. so I might get it cheap!!!
 
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I have been down there so much lately .............................. so I might get it cheap!!!

[/ QUOTE ]Yea, right, and pigs can fly....... (cue Lakesailor /forums/images/graemlins/smirk.gif)

Don't be a woooose. Take the valve off the through hull and pop in a taper plug while you clean out the valve and clean the through hull fitting's threads. Retape the threads, remove the plug and refit the valve (quickly). IIRC there should be a lock nut below the valve so tighten the valve gently and get it in the correct position then tighten up the lock nut while holding the valve. That way you are not applying any great torque to the through hull fitting. Finally pump out the couple of gallons of water you may have "spilt".

A man with your talents and nimble fingers should have no problems - A few measures of "dutch courage" is not recommended beforehand.

If really nervous how about placing a plastic bag over the fitting on the outside (held in place with some fishing line or the likes then when you open the valve or remove it the bag will block the intake - seems to work in real life /forums/images/graemlins/crazy.gif
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Lots of things you could do but at the end of the day I suspect you just want to lift the boat and redo the whole installation properly...in which case I would dissassemble the filter/skin fitting joint WITHOUT ROTATING the skinfitting where it is bedded into the hull.Then reassemble using Sikaflex.(though many on here do not like the idea of using Sikaflex cos it sticks so well!).
If you are unable to get a quick haul out,Robins idea of plugging the inlet with a bung pasted in thick grease and then redoing the offending joint whilst in the water is fine-and is what I would do-if you are confident.Not forgetting to paste a 'remove bung'note on the engine ignition key...
Alternatively pop along to your local plumbers merchant and obtain a tube of silicone-based 'external leak sealer/jointing compound' designed for curing leaking central heating joints.Clean and dry the offending joint and apply this liberally.Trouble is that it is effective and so the temptation is to leave it till next haul out time....hint hint
 
Quote

"enough to just wet a piece of tissue 1cm or so after 5 hours"

You probably exhale more moisture than that, just describing it.
 
To each his own, but I wouldn't dream of spending the money on a haul out to fix a leak which was described as results in 1cm of dampness on a piece of toilet paper after 5 hours.

If the leak 100% definitely is coming from the thread between the skin fitting and the valve, and provided that the valve isn't so loose that its about to fall off, I see no way that its going to cause any problem in the near future.

So, if it were mine, I'd keep my beer tokens and add it to the list of things to be fixed "one day". It takes a lot for me to give more of my hard earned cash out than I need to!


Chris
 
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Quote

"enough to just wet a piece of tissue 1cm or so after 5 hours"

You probably exhale more moisture than that, just describing it.

[/ QUOTE ]

That reply brings to mind another possibility, you sure it's not condensation onto the (cold) skin fitting??
 
I had thought about 'just going for it' with some form of external cover, but I wasn't sure how quickly I could get a sound bung in, what about heeling her over a bit to reduce the water pressure? I don't have a lock nut below the ball valve, maybe I should see if I can get one, in the meantime I have tried another 1/4 turn on the ball valve, easier than I was expecting! Report tomorrow.
 
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