Underwater putty recommendations - rather important!

[Billba]

Marinas usually do day rates for visitors which shouldn't break the bank. Also can you spin the seacock through 360 with the handle in the off position? Another way to stop the skin filling twisting off is to insert something that will contact the inner moulded lugs. I used a chisel gripped with a mole wrench. Could someone reach under from the dinghy and reach the skin fitting? If it was set up before hand you could lash the mole wrench to a suitable extension to save continuous immersion. Let me know the Skin fitting size and I can tell you the ID.

 

[Dipper]

Also can you spin the seacock through 360 with the handle in the off position?.

I woke up at 4am and realised that the handle needs to be in the on position to turn the valve through 360 degrees. By 4:30 I had solved it by fitting a short length of hose long enough to reach above the waterline which will still allow me to rotate the valve.

I have a file that fits perfectly on the lugs from the outside but thank you for the offer.

 

[Billba]

Well done.... sounds like you're ready. Let us know once you have finished.

 

[Dipper]

Well done.... sounds like you're ready. Let us know once you have finished.

If I sink the boat, I'm not going to admit it on here.

Thanks for the suggestion regarding tipping the boat over. I am considering that. My boat is very beamy. I'm not sure if that helps or not.

 

[KREW2]

Why not go on to the drying piles in Weymouth harbour

 

[Dipper]

Why not go on to the drying piles in Weymouth harbour

That had crossed my mind but do I need to wait for the next spring tides? I don't need to dry out fully I but do need enough depth to get on them.

 

[Billba]

Another thought I had was not to discount the PTFE tape option as it will be easier to recover from if a third attempt is needed. If say you seal it up with CT1 refloat and then discover that you had disturbed the skin fitting seal it will be far more difficult to unscrew with CT1 than PTFE. If it still leaks with say 4 wraps of PTFE and the skin fitting seal remains good then unscrew 5 turns again try 6 wraps and hope the skin fitting seal holds. If not then it will require a complete dismantle clean up all surfaces and start again but that is worse case.

 

[Heckler]

Stu, I suggest you look at the fitting instructions for the type of Marelon valve Dipper has fitted.
There is a link to the instructions in his post #16 and a video in # 14.

You will see that the backing nut normally fitted to the skin fitting is not used and that there is not one between skin fitting and valve either.

I guarantee you'll not be impressed but at least you will understand Dipper's problem better.... compounded IMO by the use of tape on parallel threads being suggested in the written instructions which he attempted to follow.

Leaving 8 threads ( he says somewhere) may also ha ve been a mistake if the end of the skin fitting then bottoms out in the valve preventing a closet fit between the valve flange and the wooden pad. ( Note 3 screws finally secure the valve body to the wooden pad,)

Vic, quite right. I withdraw most of my advice. However I get the impression that you are as underwelmed with the design and fixing method as I am!
My advice would still be, go back to basics, remove the valve, clean and reseal etc. Bodging on sompething as important as this is not acceptable.
S

 

[Dipper]

I went down to my boat yesterday and less than 1.5 litres of water had entered in three days. After I had mopped it up and removed the toilet and toilet base, I could see that the area around the seacock was virtually dry. After two hours, there wasn't even enough water seepage to fully wet a single piece of kitchen roll. I think the wood backing pad had swollen and sealed the leak in the same way that wooden boats stop taking on water after they have been launched.

I appreciate what Skipper-stu is saying buy I'm going to leave it and keep checking to ensure it stays dry. It's not an old seacock that's failing and getting worse. It's a new fitting firmly clamped either side of the hull. Any leak is irritating not dangerous. If I tried to reseat it now, I would be tightening up the valve against an expanded backing pad which might then shrink as it dried. I can refit it next winter.

Thanks for all the hints and tips. The CT1 looks particularly useful as an emergency sealant. If I ever needed to whack a wooden bung in a hole, I could use this around the bung to make sure it wasn't pushed out. A tube is now on my boat.

 

[Vara]

Be aware that even unopened CT1 has a finite life, lasts longer than Sika though!

 

[Billba]

You could of course use some of the CT1 to form a fillet around the hull to backing block join and the seacock to backing block join. This should then stop your leak/seepage. Incidentally the backing block should ideally have been sealed to prevent any moisture being absorbed and subsequent rotting of the block. Good to hear you are not going to have to play russian roulette wih unscrewing the cock whilst afloat. Cheers Bill

 

[Dipper]

You could of course use some of the CT1 to form a fillet around the hull to backing block join and the seacock to backing block join. This should then stop your leak/seepage. Incidentally the backing block should ideally have been sealed to prevent any moisture being absorbed and subsequent rotting of the block. Good to hear you are not going to have to play russian roulette wih unscrewing the cock whilst afloat. Cheers Bill

I thought of that but it would make it more difficult to remove later. I'll replace the block over the winter and encase it properly. I think it was the original one put in by the builder 35 years ago. Thanks for your comments.

 

[Billba]

In my case I used the CT1 around the seacock only and in relatively small quantities and had no difficulty when I later came to remove it. Carefully aimed chisel and light tap from mallet did the trick. I always feel happier not having to mop up on each visit but you'll obviously play it by ear. Cheers Bill