Author Topic: Bavaria 37 (2005) upper rudder bearing - revisited...  (Read 3846 times)

umu

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Hi,

I noticed sideways play in the rudder last year (visible at the top nut). Not huge, but the bonging noise this causes when going thru waves were quite a nuisance.

Attemps to reduce it by tightening the big top nut did not make any difference in regards to play (And as far as I could see when taking everything apart - the only thing turning this nut does is pull the rudder higher or let it lower as the bearings slide freely on the rudder shaft sections. This might have been different on older models  as the top bearing then was a different design).

I eventually changed the original Bavaria bearings against the Jefa bearings.

However there is still sideways play in the rudder - my guess is even the same amount as before.
It is in the upper bearing - between the bearing and its housing. Which is a surprise as the top housing was in perfect shape (as opposed to the slightly corroded lower housing).

Frankly I am a bit lost and any advice is very much appreciated!

Yngmar

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Re: Bavaria 37 (2005) upper rudder bearing - revisited...
« Reply #1 on: May 29 2018, 14:34 »
Could be wear on the bearing housing. This can happen when the bearing ball seizes on the rudder shaft and starts turning in the housing instead. Or could be the upper housing never was the right size, or the new bearing the wrong size for it, however you want to put it.

In my case the original rudder shaft wasn't manufactured according to plans, so ended up sleeving it to fit the new Jefa bearing (that was made to plans). In your case the play is between the bearing ball and the housing, which isn't so easily fixable due to the spherical surface.

To fix, you need either a bearing ball that perfectly fits the housing you have, or a new housing that fits the new Jefa (presumably roller) bearing.

You're right that the shaft isn't a tapered design (it's stepped instead), so tightening the nut only pulls the rudder up but doesn't reduce play anywhere (unless you crank it so far up you hit one of the steps, which won't help for long).
(formerly) Sailing Songbird  ⛵️ Bavaria 40 Ocean (2001)

tckearney

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Re: Bavaria 37 (2005) upper rudder bearing - revisited...
« Reply #2 on: May 30 2018, 11:46 »
How are you determining the play ?  My B42 2000 model has upper and lower bearings that have a certain amount of "tilt" if you try movement from the bottom of the rudder. 

dawntreader

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Re: Bavaria 37 (2005) upper rudder bearing - revisited...
« Reply #3 on: May 30 2018, 14:20 »
I have a B37 2006 with replacement Jefa Bearings fitted 2014/5  and there is no sideways movement - the rudder is solid but sensitive to the slightest movement of the wheel. The captive nut at the top of the stock is only 'nipped' shut (so not over-tightened).

Stockie

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Re: Bavaria 37 (2005) upper rudder bearing - revisited...
« Reply #4 on: June 02 2018, 03:46 »
I’ve just purchased Jefa roller bearings, awaiting my August haul out.  So good to hear Dawntreaders experience was positive.  My boat is also a 2006 B37
I ordered the 58 mm bottom and top 40mm after measuring my shafts in situation and concurring with Jefa info.  In response to the thread initiator, I guess the top housing is oversized?  At least it is the easier one to get access to, so more money on a new casting should remedy it, or carefull building up on the housing, but I imagine pressure points in that area could lead to binding, especially when under load.
Cheers Richard

umu

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Re: Bavaria 37 (2005) upper rudder bearing - revisited...
« Reply #5 on: June 08 2018, 09:07 »
There is nothing wrong with the Jefa bearings, they are up to the spec and have no play between rudder shaft and bearing.
The problem is the upper housing which seems not oversized but worn (as play is different sideways vs. bow/stern direction).
While Jefa could provide the lower bearing I could not locate a source for the upper bearing. And having it made is beyond the capabilities of the metal shops I could get hold of - it requires some pretty fancy 3d milling.

buttonfreebie

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Re: Bavaria 37 (2005) upper rudder bearing - revisited...
« Reply #6 on: June 08 2018, 16:45 »
Hi Umu take a look at my response on 23Feb 18 to the rudder bearing topic

umu

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Re: Bavaria 37 (2005) upper rudder bearing - revisited...
« Reply #7 on: June 12 2018, 12:37 »
@buttonfreebie
thanks for your advice about JP3 / International Boat Spares; while they have housings for the bottom bearing that would fit
the top bearing housing that is on my B37 (made by Seaway) is significantly different from their versions and would not fit without major rework on the deck.