Tight rudder bearing...what to do?

[Iain C]

My boat has a skeg hung, non-balanced rudder. I took it off over the winter to rebuild the inside of it and thought I should replace the bottom bearing before launching. The top bearing is a tufnol tube that goes from the top of the skeg to the cockpit floor. The bottom of the skeg has a bronze heel, that bolts on from underneath, with a replaceable bearing. It was tufnol, and there was a fair bit of slop in it.

I had a new one made out of actetal over the winter. The fit on the shaft was very good...it would spin but there was no slop. However with the rudder in position, it's very tight...the reason is that either the shaft is bent or the tube has worn, the net effect being that the bottom of the rudder shaft, without the bronze heel on, is about half an inch back from the vertical, where it should be. This accounts for the "off centre" wear pattern of the old bearing. The best way I can describe how it's worn, is as if someone has tried to drill out the bearing a bit bigger, but got the drill off the vertical, and stopped halfway through...there's a step halfway down the bearing surface.

There's enough flexibility for me to bolt everything back where it should go, but the tiller is now a bit stiff. I can move it with one finger so it's not that bad, however it's a case of overcoming that initial "sticktion" to get it moving.

Do I just put the old one back in, and put up with the slop, or just be grateful for a little bit of assistance keeping the tiller straight and wait for it to loosen up? Perhaps immersion will add a little bit of lubricant? Opening up the new bearing is not an option as it will probably be even sloppier than the old bearing as the movement will be in two planes rather than one.

Thoughts?

 

[rob2]

I'd be inclined to go with the new bearing. As you say, it may be easier with water as a lubricant - with the benefit that it won't kick out of your hand when reversing! When refitting mine, which has a bearing at the bottom of the skeg and another a foot above the cockpit sole, the misalignment was nearly an inch. It's fine once assembled, though.

Rob.

 

[colhel]

If it's a constant stiffness, I'd live with it. If it frees up a bit in certain positions, would it be possible to turn the shaft/bush in the rudder until the free bit is in line with the tiller? Another possibility would be to loosen the bolts and get someone to move the tiller while you tighten them, if it stiffens up loosen again,use feeler gauges to align the the bush until it feels free. Then replace feeler gauges with suitable shim. Must be an easier for me to describe that.

 

[ianfr]

Iain

When I put my rudder back on, I had the same half inch gap before doing up the heel fitting. The rudder is very SLIGHTLY stiff but my impression is that most of that will disappear when the boat is back afloat. A little water will always get into the tube making it move easier. Perhaps pour some water down from above to try it?

My bottom bearing isn't showing the same wear pattern, only some scoring due to the top ring not being locked thus allowing the weight to fall on the top surface of the bearing. Now it is adjusted correctly there is no play.

I am now ready to launch with a week to spare

Regards

Ian
Sabre 27 Apogee

 

[NPMR]

Hi Ian C

The new bottom bearing on my Sabre 27 rudder went on yesterday afternoon. So stiff initially, that it took some real effort to shift it.

I am however very confident that it will free up a) when immersed and b) with a little wear.

My shaft, too, is a little bent and so the bearing does not last many seasons before it needs replacing again.

I have been unable to get the shaft straightened but in use, it seems to make no noticeable difference to the sailing performance of the boat.

 

[misterg]

...Opening up the new bearing is not an option as it will probably be even sloppier than the old bearing as the movement will be in two planes rather than one.

Thoughts?

Make up a new, new bearing with an eccentric bore and/or fettle the shoe so the alignment is better??

Andy

 

[Iain C]

An eccentric bore? I saw sown of those propping the bar up on Sunday!

Thanks all, I think I will go sailing and see how things are after a few months.