Monday 29 January 2007

Removal of Jaguar 22 Keel

If you have read any other information on the Jaguar 22 on any other website you'll find that the boats scariest weak point is the keel and the keel bolt, closely followed by the toilet. Stories tell of keels falling off, keel boxes being ripped apart and boats capsizing and sinking. Enough to make any Jag. sailor a little nervous. As our Jag. was built circa. 1980 and I knew that the last time the keel had come out was at least 10 years ago, we thought it prudent for an inspection. The other thing mentioned regarding the keel in the handbook recommends not to moor the boat in salt water as there seems to be 'negative' electrolysis between the cast iron keel, stainless hanging bolts and bronze keel. i.e. you launch the boat in the Spring and by the end of the season the keel has half vanished.The keel drop has been on the cards since November but we finally got around to it last week and it all went very smoothly, using a very simple method.

Tools required:
Trolley Jack
13mm or 5/8 sockets or spanners
Knocking stick (hammer)
A couple of blocks of wood
Screwdriver
The first piccie shows the keel in it's normal position on the trailer. We removed the trailerboard which the keel rests on, so that the jack could take the weight of the keel. Using the keel winch the aft section of the keel was lowered on to the trailer to allow the trailer to take half the weight. As the top of the keel at the forward end above the pivot hole remains in the keel casing the keel cannot 'fallover'. Bear in mind though the keel weighs 200kg+.
The jack was positioned under the front of the keel about 20cm aft of the leading edge. The weight of the keel and boat was then taken on the jack.
On each side of the keel are 4 threaded studs with nuts. These are all stainless with two locating the plate and two holding the keel bolt hangers in. Undo carefully the two outer nuts being sure to not shear the studs. Though to do this you would have to use a lot of force. On Aretia the inner two studs on either side had double nuts. If you try an undo only the outer nut you will find the whole stud spins, so grip the top nut with on open ended spanner to stop this. I'd suggest taking the outer nut off completely and only loosen the top nut about 10mm.
We then lowered the jack slightly to check we'd undone the correct bolts and you should see the whole plate fall away slightly. Jack back up and proceed to finish removing all the remaining nuts. The plates should then come of easily once you have a screw driver behind it.
Now it's time to lower the keel completely. Very carefully lower the jack, mm x mm. You may find that every now and then you will need to whack the keel with the hammer as it catches on the way down. We also jacked the keel back up every now and then, just to ensure it was coming out true. You should start to see the keel hangers which are basically bearing supports showing. As soon as these are clear you can pull the hangers away from the keel and give the bolt a nudge out of the keel. Inside the keel casing the top of the keel should still have a good 6-8 inches left before it would come out of the casing completly. Our bronze pin was almost pristine the hangers were in good condition and only very, very slight ovaling of the hole in the keel itself.
It's then a case of putting the hangers back in, pin in and gently jacking the keel back up. Don't be a pillock and do what I did and put the first hanger in upside down. Be careful not to damage the threads on the bolts. A little gentle persuasion from the hammer on the keel helps to true the upward movement. Once all up, add the plate and bolt up tight. Once secured drop the jack back out of the way. After completing once it should be only a half hour job every year.
It was then a case of checking the keel winch wire. Again a 5 min task. Next.....removing the toilet (heads).

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