Keel bolts checking - would you?

[peter2407]

I know I am building up a mega list of activity, but I have a month off so want to have a list of indoor and outdoor useful work to do, so: Keel bolts - would you check them while the boat is in the cradle? If yes:

a. What is the normal 'design' ie does the bolt screw into a fitting/nut in the keel, or does the keel have 'taps' built in - my keel is lead btw
b. What should I look for before taking the boat of the water (ie can I mark the keel bolts in some way to see if there is movement - this is on the premise that the boat in the water has support from the water, and when in the cradle I am assuming that the keel will be on the ground but when in the lift there is no support ... this may be a false premise)
c. Apart from a big bar, what should I prepare for when extracting them
d. When they are (eventually) out, what do I look for?
e. Where can I get replacements (even if there are no issues I may well replace them anyway)
f. What to do when putting them back

TIA as ever.

BTW, the reason for checking is that when the boat was out of the water a few years ago, I noticed what I thought was a 3 inch by 1 mm 'line' at the front of the keel where I think it connects to the stub, and it has niggled ever since. That said, the paint in the bilge around the bolts hasn't cracked our shown issues.

 

[Norman_E]

"Normal design" may mean different tings to different yacht builders. In an iron keel most keel bolts are actually studs set into tapped holes in the iron, but lead keels may have steel nuts cast in, headed bolts cast in or studs bent to J shape and cast in. There may be other variations. You need someone who knows what your boat's builders did. If studs or bolts are cast in, you cannot replace them so before doing anything you really need to know how it was put together.

 

[pvb]

I don't think I'd bother unless the boat was 20+ years old and/or exhibiting signs of movement/leakage.

Still, I have a new Bavaria and its keel is very firmly attached!

 

[sailorman]

Yes BUT she is 6 months old, could be worth a look

might be worth an ask in the lounge :sleeping:

 

[pvb]

Yes BUT she is 6 months old, could be worth a look

might be worth an ask in the lounge :sleeping:

Actually, Bavaria's website now stresses the integrity of their keel structure - "Particularly strong keel bolts ensure a force-fit to the keel – twice as many as is usual in yacht construction."

 

[Niander]

Paranoid Bavaria!

 

[pvb]

Paranoid potential buyers, I think!

 

[knuterikt]

"Normal design" may mean different tings to different yacht builders. In an iron keel most keel bolts are actually studs set into tapped holes in the iron, but lead keels may have steel nuts cast in, headed bolts cast in or studs bent to J shape and cast in. There may be other variations. You need someone who knows what your boat's builders did.

Agree

If studs or bolts are cast in, you cannot replace them so before doing anything you really need to know how it was put together.

Can be done - but I think this is a job for professionals.

Read more here http://marskeel.com/production/repair-modifications/keel-bolt-replacement/

Think this company can do the same http://www.oerkild.com/html/engelsk.html

 

[Kelpie]

This has been niggling in my mind too.
How would I go about finding out what sort of keel bolts I have? Only about 50 of my boat were made, in the early 70s, by Deacons Boatyard. I wonder what the chances are they still have the information squirreled away somewhere?

 

[sailorman]

http://sparkmanstephens.blogspot.co.uk/2011/07/design-1873-deb-33.html

 

[Ruffles]

On a fibreglass boat with an iron keel (sounds like this is what you have?) I think there are two separate issues. The integrity of the bolts and the integrity of the keel hull seal. You can draw the keel bolts one at a time quite safely with the boat on the hard. Costs nothing. To renew the seal is a different issue. I've not done this but makes sense to get the yard to do it as you'll need the hoist and lots of people!

By the way, I've heard that oil is used to preserve the thread between the stud and the bolt. Anyone know what oil it is?