howdy
The vessel i work on is up on the slips ..it is primarily a stink boat ,,,but in its defense it does have a mast ...and a sail ....(somewhere) and is wooden .....the seacock for the cooling system has a small problem with the end of the thread , which i may be able to repair tomorrow by replacing the threaded bolt ......and then refitting the seacock .....Any suggestions as to which type or brand of sealant ....for the base of the seacock flange ,,,it bolts onto a timber fitting inside the hull ,,,and the top flange bolts onto strainer......it has a rubber gasket in reasonable condition....all suggestions welcome ....marine grade silicon was my first thought but a little bit of research has me in a quandry ? The other fly in the pie is it has to be back in the water by high tide thursday so curing time is an issue also.......anybody?

Used this stuff on my depth sounder and sum log and it worked well. I also used it extensively above the waterline and never had any failures. (leaks). Probably likes the surface you are applying it to, to be dry, as in really dry not "she'll be right mate" dry.

Out with the heat gun on the timber first maybe.

Sikaflex will out last the substrate and uses water in the air to set it, it is my preference

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Prawnhead said..
howdy
The vessel i work on is up on the slips ..it is primarily a stink boat ,,,but in its defense it does have a mast ...and a sail ....(somewhere) and is wooden .....the seacock for the cooling system has a small problem with the end of the thread , which i may be able to repair tomorrow by replacing the threaded bolt ......and then refitting the seacock .....Any suggestions as to which type or brand of sealant ....for the base of the seacock flange ,,,it bolts onto a timber fitting inside the hull ,,,and the top flange bolts onto strainer......it has a rubber gasket in reasonable condition....all suggestions welcome ....marine grade silicon was my first thought but a little bit of research has me in a quandry ? The other fly in the pie is it has to be back in the water by high tide thursday so curing time is an issue also.......anybody?

Silicon has no place on a boat, especially a wooden one. Silicon is ok to seal the glass on fish tanks or some gaskets in engines.
You can not paint over silicon either.

Stick with Sikaflex or any of the other sealants of the same ilk. Assemble the skin fitting and wait 20 minutes or so for the Sikaflex to skin over and then prime or overcoat with antifoul.

Selleys Blockade. A bit hard to find but worth the effort. I used it under a ply patch on a big hole in my cat a few years ago and it kept the hull dry for a month while I waited for a haul out. I always keep a tube on board.

Another vote for Fixtech based on my experience of it sticking well to timber (and Grp).

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PhoenixStar said..
Selleys Blockade. A bit hard to find but worth the effort. I used it under a ply patch on a big hole in my cat a few years ago and it kept the hull dry for a month while I waited for a haul out. I always keep a tube on board.

Since you have experience with Selleys Blockade, can you say whether it hardens in the tube after first use or whether you kept using the same tube for, say, a year or longer?

(Whenever I have bought Sikeflex 291, I have always had to throw out the tube after one use; hardens up within months despite tricks I have tried to seal the top).

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Karsten said..

PhoenixStar said..
Selleys Blockade. A bit hard to find but worth the effort. I used it under a ply patch on a big hole in my cat a few years ago and it kept the hull dry for a month while I waited for a haul out. I always keep a tube on board.

Since you have experience with Selleys Blockade, can you say whether it hardens in the tube after first use or whether you kept using the same tube for, say, a year or longer?

(Whenever I have bought Sikeflex 291, I have always had to throw out the tube after one use; hardens up within months despite tricks I have tried to seal the top).

It is not too bad. You will loose what is in the nozzle after a while but if you have some spare nozzles it is OK. it skins off where exposed so it can be painted but takes forever to harden right through. No tensile strength so it just waterproofs fixings - above and below the water, and it sticks underwater so it's good for emergency repairs.

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Karsten said..

PhoenixStar said..
Selleys Blockade. A bit hard to find but worth the effort. I used it under a ply patch on a big hole in my cat a few years ago and it kept the hull dry for a month while I waited for a haul out. I always keep a tube on board.

Since you have experience with Selleys Blockade, can you say whether it hardens in the tube after first use or whether you kept using the same tube for, say, a year or longer?

(Whenever I have bought Sikeflex 291, I have always had to throw out the tube after one use; hardens up within months despite tricks I have tried to seal the top).

Try storing in the freezer.

A trick I use with sealing silicon tubes is to stick the nozzle up the finger of a
rubber glove and tie the rest of the fingers tightly around the tube...works for me.

I use the other type of stop, on the rhs. It is threaded and is really good. I reuse the same tube for a long time.
The type on the lhs. is useless. So is the nozzle.

I dont know how good this would be for your repair but i have talked to guys that have used to do roof repairs while water was flowing over the section they fixed

Sikaflex changed the formular since when I was young. We would just put a bolt or screw into the nozzle and she was ready for use weeks/months after. I noted about 5 years ago once you crack the tube it went hard if you Didn't use the whole tube strait away. I moved to fixtec 15 and will not look back! Same job achieved with value for money!

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southace said..
Sikaflex changed the formular since when I was young. We would just put a bolt or screw into the nozzle and she was ready for use weeks/months after. I noted about 5 years ago once you crack the tube it went hard if you Didn't use the whole tube strait away. I moved to fixtec 15 and will not look back! Same job achieved with value for money!

Exactly the same experience for us. Fixtech will work underwater. And it's an Oz product to boot.