Well, yesterday we went into the steering compartment to dismantle the worm gear steering.... there was circumferential play in the steering head.
To our surprise, the steering head came off the top of the rudder post with not too much trouble. There was some enlargement of both the shaft keyway and of the bronze steering head keyway. It was not going to fail....
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Looks like we can recover some of the play it by cutting a new keyway in the steering head, and we will do our best to make the new key fit the shaft keyway a little better. If we can recover most of the play, then we will be good for another while yet, 31 years on.
A less welcome surprise is that you cannot get the steering worm gear shaft out of there without smashing the teak front off the helmsman's steering seat.... teak planks and all. Even if you strip the mechanism right down to just the shaft and the followers, it still won't come out.
There is some play in the forward worm gear follower, but not much on the aft.
Here is a worm gear with one (aft) follower...
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...we have two followers, fore and aft, but it gives an idea of it.
This winter, we will have to rebuild the seat and we will make the front of it removable so that we can get the entire worm gear steering mechanism out of there.
Another marvellous bit of planning from the Tiawanese yard. Beautiful lines to the ship, and good in a big sea, but, yet again, more stupid, utterly-avoidable nonesense.
What, on teak, Rockter?
Yes, crowbar, %$*"£*$* crowbar!