keel bolts

PabloPicasso

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Due to Brexit I had to change to a non UK based broker. As a result I had to get a new survey. the surveyor recommended pulling the aft most keel bolt on my 26ft sailing boat, something i was not looking forward to attempting. I've heard all sorts of stories about bending pry bars/scaffold pole/etc and how difficult it is to get the leverage in the small space of a cabin sole.

Anyway, as it turned out it was very easy to do with a bit of know-how and the right tools.

The right tool is, I have found out, an impact gun. It made light work of removal and reinstallation of the keel stud.
Here is a link to my youtube video of same. Sorry there is no commentary, I'm a bit of an IT numpty. Have a look from 47sec in. It actually took about 5 or 6 minutes of hammering with the impact gun, and then the bolt just came out. Thankfully it was in good condition, so we just cleaned up the surface rust and put it back.


I can see why the surveyor wanted me to pull the bolt, it looked really crusty. However, all the crustiness was some sort of coating that was peeling off. Once cleaned up the bolts/nuts were fine, only a bit of surface rust. Not bad after 40years. You can see this clearly in the video clip if you watch the whole thing
 
Really wish surveyors would not make such unnecessary recommendations. As you discovered after all that work really was no need to disturb the bolt. If there is no sign of water coming in the boat then the only way that the bolt can be subject to corrosion is if the keel/hull joint has failed. If it has not then leave well alone except perhaps for cleaning up the top of the bolt to check the washer has not corroded away.

Well done for tackling it though - if it had been a survey on my boat like that I would have told the surveyor to get lost, for the reasons stated.
 
Typical surveyor making you do work to cover him against missing anything. Every survey I have read has so many exclusions on what they have checked like employ an engineer to check the engine, an electrician to check the electrics, a rigger to check the rigging, sailmaker to check the sails, etc. Unfortunately insurance companies insist on an independant opinion of the boat. When I bought Concerto I did not agree with a couple of recommendations the surveyor made and I conducted my own checks and the "problems" he wanted investigated were not a problem at all, just like the keel bolt.
 
We shopped around and Pants came up as the best insurer, for a variety of reasons. They wanted a survey - which seemed reasonable. The surveyor and survey were fine, Pants were happy. We were also happy as my main concern was the rigging and the survey was a retired rigger. 2 years later Pants changed their underwriter and Pants said the new underwriter wanted a survey (I pointed our we had 'just' had a survey). We had not made a claim with Pants. We don't insure with Pants now. new insurer was happy with the 2 year old survey.

Funny world.

Jonathan
 
Annoying for a survey….

But another win for impact! The big Milwaukees now challenge any air setup. Way easier and safer than trying to swing a massive pry bar/pole in the saloon.
 
Yep, I agree with the comments so far. Surveyor made me do it. But at least I know the keel attachment is sound now.

My advice would be to beg, borrow, (best not to steal hey) an impact gun for this type of work. They were designed for this sort of job, what a great tool.

Can you hire an impact gun from tool hire companies? I was very lucky that John who sails with me is an excellent mechanic and had access to the impact gun. A big thank you to him.
 
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You could try wrapping the exposed nuts in Denso tape. It is impregnated with a sticky greasy goop and is used a lot offshore to protect exposed nuts and prevent corrosion. It would make it easy to check the nuts next time.
I haven't tried it on keel bolts myself as I happily have an encasulated keel
 
Impact guns are the future of keel bolt maintenance.

It got used when we changed the saildrive diaphragm a yea or so back.
What a great tool.
 
Denso tape. Seems like a good idea.
Denso tape is incredibly good at corrosion prevention. I know of subsea tubulars wrapped in it for months coming up bright and shiny. I wrapped the carbon steel electric motor of my windlass with it after various paint systems performed poorly (motor is in the anchor locker). After something like 8 years the motor is still rust free. Only problem is it is very sticky and unpleasant to touch so I wrapped it in polythene.
 
How will it be beneath the sole boards in the cabin? I can imagine it is unpleasant to touch.

How easy is it to remove?
 
Pablo. Can you tell me please what make and model of impact wrench you used?

I recently bought myself an impact driver and I am thinking of complementing it with and impact wrench.
 
It's a milwaukee. It's not mine but I'll see if I can find out the model.
It was am M18 FMTIWF12. That was a 1/2" (13mm) drive and 18V.
That tool is a few years old now I'd say, but there must be a modern equivalent. I see a Milwaukee 18 volt high-torque M18 model available online. Perhaps that would do, but they are expensive if you don't intend to use it a lot. Perhaps you could hire one?
 
Denso tape is incredibly good at corrosion prevention. I know of subsea tubulars wrapped in it for months coming up bright and shiny. I wrapped the carbon steel electric motor of my windlass with it after various paint systems performed poorly (motor is in the anchor locker). After something like 8 years the motor is still rust free. Only problem is it is very sticky and unpleasant to touch so I wrapped it in polythene.
I’ve used Boshield to similar good effect. A spray on brown coating. Sticky for ever also.
 
It was am M18 FMTIWF12. That was a 1/2" (13mm) drive and 18V.
That tool is a few years old now I'd say, but there must be a modern equivalent. I see a Milwaukee 18 volt high-torque M18 model available online. Perhaps that would do, but they are expensive if you don't intend to use it a lot. Perhaps you could hire one?
Thanks for that.

Still available: Milwaukee M18FMTIWF12-0 M18 Mid Torque Impact Wrench 1/2" FR

I'll keep an eye out on eBay for one, or hire if necessary
 
Pablo. Can you tell me please what make and model of impact wrench you used?

I recently bought myself an impact driver and I am thinking of complementing it with and impact wrench.

The only difference is the impact driver has a1/4" hex socket and the wrench has a square section driver head 1/4, 3/8 or 1/2" and is able to deliver a greater torque, my impact driver ( just bought a new one as I gave feckless my previous one rather than let him borrow it) is capable of delivering up to 180Nm which I think is ample for most jobs the 610Nm of the Milwaukee is huge but I guess it comes in useful for breaking the initial bond but I wouldn't want to use it to tighten up much, too many grease monkeys and tyre fitters stretch bolts and studs by using them.
 
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