How much wiggle is OK in a rudder - SailNet Community
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post #1 of 22 Old 03-18-2019 Thread Starter
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How much wiggle is OK in a rudder

I've been looking at a few boats recently.

https://www.dropbox.com/sh/2llhwg4nv...jyG3uCCVa?dl=0

I noticed on the boat above the tip of the rudder will move starboard and port without turning about 3/8".

I've been looking a quite a few boats and find that some don't move at all, some less and some more.

I'm assuming any movement is indicative of a rudder bearing issue.

How much is normal?
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post #2 of 22 Old 03-19-2019
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Re: How much wiggle is OK in a rudder

slop in linkage?
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post #3 of 22 Old 03-19-2019
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Re: How much wiggle is OK in a rudder

Do you mean that the rudder turns around the shaft? In other words, the shaft doesn't turn, but you can move the rudder on it? If so, this is never normal.

If you mean the rudder and shaft turn a bit, this most likely is just lash in the steering system.

Worn bushings will allow the shaft to move side to side. You need to grab it at the bottom and move it left-right, forward-back to determine.

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post #4 of 22 Old 03-19-2019
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Re: How much wiggle is OK in a rudder

Not sure what you mean? If I move my rudder, the shaft turns with it, There's no wiggle. There's not much, if any, play in the wheel either; i just replaced all the cables 2 years ago.
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post #5 of 22 Old 03-19-2019
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Re: How much wiggle is OK in a rudder

It sounds like he's referring to the rudder wiggling port to starboard, not turning on it's axis. Clearly, if its a small boat with a gudgeon and pintals, this would be pretty common to have some play. For a spade rudder, with a water tight rudder shaft, I've not heard of any play like this being acceptable. May only need a new shaft bearing, but sounds like something is wrong.


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Re: How much wiggle is OK in a rudder

david, you need to clarify exactly what is moving. If the entire rudder, including the rudder post, can "wobble" somewhat, that's a worn bearing(s). Wobble without any turning involved.

If the rudder can actually wobble OR turn while the rudder post is not moving, then you have an internal rudder failure. Expensive.

If the rudder and post are turning a little, as one unit, without the helm moving, then you have slop in the steering, probably in the cables.
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Re: How much wiggle is OK in a rudder

Definitely not slop in the linkage.

Not rotating the rudder just direct lateral movement at the bottom end starboard and port about 3/8".

So not a lot but some.

I did not try for and aft to confirm but should have.

It is definitely rudder bearing. My question is how much if any is normal or acceptable.

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Re: How much wiggle is OK in a rudder

Quote:
Originally Posted by colemj View Post

Worn bushings will allow the shaft to move side to side. You need to grab it at the bottom and move it left-right, forward-back to determine.

Mark
Yes this is what happens?

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Re: How much wiggle is OK in a rudder

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Originally Posted by hellosailor View Post
If the rudder can actually wobble OR turn while the rudder post is not moving, then you have an internal rudder failure. Expensive.
Good idea to check that too but that is not what I saw.

See other answers.

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Re: How much wiggle is OK in a rudder

I'm not too concerned about slop in the system as cables can be tightened or replaced.

As hellosailor mentioned an internal failure of the rudder webbing is a big deal but that is not what I saw.

I saw what I assume is wear in the bearing. I don't know how big a job replacing the bearings are and how much wear is allowed and if the surveyor will make a fuss about it.

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