Please, Keel Bolts advice needed

[Martin CY]

Hi All
I am working on the keel bolts of my Hunter Horizon 23 (twin keel). There are 5 nuts on each keel. Most of them are in very good condition with almost no rust, but the silicon arround the nuts has peeled off and some of them are not tight enough.
So I have decided to remove one nut at a time, remove any old silicon and put them back together.
1) What tipe of sealant shall I use ? ( Sykaflex 291i ? )
2) Shall I put sealant between the 2 washers or only on the lower one?
3) Is it ok to use thread-lock glue when installing the nut or shall I Just apply sealant on the threads.
4) one of the nuts is very rusty (caused by rain water) andstuck, but not leaking. Any advice how I can remove it? I have tried wd40. Or shall I just leave it there as it is for the time being?
5) Is it a good Idea to cover the bolts with sealant or better to leave them open in order to re-torque when needed .
Any advice will be highly appreciated !))

 

[vyv_cox]

First, are you sure the existing sealant is silicone? Just one of the problems with this material is that it can inhibit the cure of many other sealants and paints. So if you are sure it is silicone you will need to clean it all off thoroughly before using anything else. Sikaflex 291i is good, as is Puraflex 40 for half the price.
2. I am not sure what benefit the sealant will give you. If rebedding the keels it is normal to apply a lot of sealant to the join between them and the hull, some of which will extrude up the bolt holes. Its purpose is to prevent water from reaching the bolts. Applying it inside the boat seems pointless.
3. No need for thread lock if the nuts are tight enough.
4. Ultimately you can cut it off. If you are doing a decent job I would certainly not leave it there. Nut splitters are available, or you may be able to partly grind it and use a chisel with a big hammer. It depends on access.
5. In production boats the keel bolts and nuts are usually coated in Flow-coat, GRP gelcoat with added wax. In your case I would torque all nuts to the required figure and then paint them.

 

[Ian_Edwards]

I'd give the nut a good soaking in Plusgas, or even diesel, and leave it a few days before trying to remove the nut, in my experience both are better than WD40 as a penetrating oil. I'd also invest in or borrow (if you haven't got one already) a full hex socket so the it support the nut, hammer it on if necessary, and then use a long bar as a leaver. It's amazing what will come undone with that combination.

 

[seumask]

I'd give the nut a good soaking in Plusgas, or even diesel, and leave it a few days before trying to remove the nut, in my experience both are better than WD40 as a penetrating oil. I'd also invest in or borrow (if you haven't got one already) a full hex socket so the it support the nut, hammer it on if necessary, and then use a long bar as a leaver. It's amazing what will come undone with that combination.

Dam around nut with Plasticine, and fill with diesel, or plug gas for a day or two.

 

[vyv_cox]

There are many products marketed under the WD40 name. I find their penetrating oil as good as those of others.

 

[Ian_Edwards]

Hi Vyv, I'm sure you're correct, I was referring to the original product, water displacement version 40, developed in 1953, a can of which was essential to keep my mini distributor working in heavy rain in the 1970's.
In a similar way I use Plusgas as general description of a penetrating oil, in much the same way as Hover or Jubilee Clamp to refer to a vacuum cleaner or a hose clamp.

 

[Martin CY]

First, are you sure the existing sealant is silicone? Just one of the problems with this material is that it can inhibit the cure of many other sealants and paints. So if you are sure it is silicone you will need to clean it all off thoroughly before using anything else. Sikaflex 291i is good, as is Puraflex 40 for half the price.
2. I am not sure what benefit the sealant will give you. If rebedding the keels it is normal to apply a lot of sealant to the join between them and the hull, some of which will extrude up the bolt holes. Its purpose is to prevent water from reaching the bolts. Applying it inside the boat seems pointless.
3. No need for thread lock if the nuts are tight enough.
4. Ultimately you can cut it off. If you are doing a decent job I would certainly not leave it there. Nut splitters are available, or you may be able to partly grind it and use a chisel with a big hammer. It depends on access.
5. In production boats the keel bolts and nuts are usually coated in Flow-coat, GRP gelcoat with added wax. In your case I would torque all nuts to the required figure and then paint them.

Thank you for your reply Vyv !
It took me a while to get back but since I've stopped my job I have plenty of time to fix my boat ))
1) yes I'm sure it is a sealant, white colour, similar to sikaflex but harder (will try to upload some photos tmrw)
2) I also think it is pointless, but originally there were a lot of sealant between the washer and the nut from inside.
4) Have tried many different ways. My main problem there is very limited space to work. I will try to use gearbox oil with acetone. Hopefully it will work, otherwise I will buy a nut splitter.

 

[Martin CY]

I'd give the nut a good soaking in Plusgas, or even diesel, and leave it a few days before trying to remove the nut, in my experience both are better than WD40 as a penetrating oil. I'd also invest in or borrow (if you haven't got one already) a full hex socket so the it support the nut, hammer it on if necessary, and then use a long bar as a leaver. It's amazing what will come undone with that combination.

Thanks Ian !
Will try soaking in Gearbox oil mixed with acetone 50/50. Already bought a hex socket. Unfortunatelly I have no access to use a hammer. Hopefully the gearbox oil will work otherwise a nut splitter will be the only way.
Thanks !