Tiller / skeg bearing

[Bobbybass]

Hi all.

 

I wonder if anyone can tell me the general setup that forms the bottom tiller bearing ?

 

Over the past few years , whenever I return to the boat after some month, the tiller is totally stiff.

Last year I did a long run and it didn't ease up. It's not pleasant to spend a day navigating.

 

I have replaced the top bearing ...and in doing so the tiller is free to flop around ( is not jammed at the top ).. and lifting the tiller makes it a bit more free.

 

I purchased one of those underwater cameras that is on the end of a long lead to put it down and see the problem...and then saw the problem ? ....or rather... couldn't see it.

 

In the marina my boat sits on a small river about 20 feet wide. I have found that the river had kindly deposited a big sand bar under the boat and the bottom swivel is under the silt. The river also builds up thick solid 'concrete like' stuff on the hull that protects it, hence the blacking is only every 5 years and the anodes never corrode.

 

As the water is only less than 3 feet deep, I'm going to get in there...and by feel...try and clear the bottom bearing.

 

Hence...my question. What am I ' feeling for' under the silt ?

If I get a 'picture' of it in my mind, I will have some idea of how to clear it...bearing in mind that it may be solid with calcite and will need a good scrape with some tool...ie... screwdriver ?

 

Thanks all !

[Alan de Enfield]

Assuming you are talking about a narrowboat, you will have a long flat bit of metal coming from the back of the boat, past the prop and it will have a 'cup' welded onto it.

The rudder 'shaft' will be coming down vertically and the end will sit in the cup.

There is not (normally) any bearings as such.

 

 

 

[Bobbybass]

Yes...standard narrowboat.

 

That cup arrangement makes sense. I guess that a build up of rock hard calcite in that cup would cause my problem. I can't think of any other reason it is stiff considering that the top of the rudder is free.

 

Thank you for your comments and excellent photos !

 

?. 

 

Bob

 

 

[Mike Adams]

Are you sure the sure the bottom bearing isn't being hit against the ground by changing water levels or wash from other boats. That could push it upwards making it tight or it could be filling up with silt. Impossible to say without seeing it.

[Jen-in-Wellies]

To call the cup on the skeg of most narrow boats a bearing is an insult to all bearings made since the 18th century! It is very crude and simple. Possible that @Mike Adams says, it is being filled with silt around the end of the rudder pin.

 

Jen

[Alan de Enfield]

1 minute ago, Jen-in-Wellies said:

To call the cup on the skeg of most narrow boats a bearing is an insult to all bearings made since the 18th century! It is very crude and simple. Possible that @Mike Adams says, it is being filled with silt around the end of the rudder pin.

 

Jen

Many years ago, as impoverished farmers, we would make a gate 'hinge' by burying a glass jam-jar in the ground, the bottom of the gate would be extended by a few inches so it could sit in the jar. It made a great 'bearing'.

 

(Obviously we couldn't afford to buy Jam, and had to scavenge jam jars from anywhere we could - as a child I did have a good collection of Golliwog badges after sending off the labels to the manufacturer)

[robtheplod]

3 minutes ago, Alan de Enfield said:

Obviously we couldn't afford to buy Jam, and had to scavenge jam jars from anywhere we could - as a child I did have a good collection of Golliwog badges after sending off the labels to the manufacturer

Wow, what a reminder ... i did this as well!!!

[Dr Bob]

21 minutes ago, Alan de Enfield said:

 

 

(Obviously we couldn't afford to buy Jam, and had to scavenge jam jars from anywhere we could - as a child I did have a good collection of Golliwog badges after sending off the labels to the manufacturer)

OMG, how racis accurate! That's what we did as well. That's history for you. Times change but our history doesn't. 

Alan, I would have given you a greenie as well as a horror if we were allowed to.

[Alan de Enfield]

10 minutes ago, Dr Bob said:

I would have given you a greenie as well as a horror if we were allowed to.

I'll give you one then, just to balance it out.

[BEngo]

57 minutes ago, Bobbybass said:

Yes...standard narrowboat.

 

That cup arrangement makes sense. I guess that a build up of rock hard calcite in that cup would cause my problem. I can't think of any other reason it is stiff considering that the top of the rudder is free.

 

Thank you for your comments and excellent photos !

 

?. 

 

Bob

 

 

First check that the rudder is actually sat in its cup.  The symptoms you describe are what happens when the rudder is lifted out of its cup and  is binding on the counter or skeg.

 

If that is OK, if you dismantle the top again, You may be able to remove the rudder and stock by lifting it out of the skeg and lowering into the water  (attach some ropes to the top and the end of the blade so you don't lose it).    If you cannot lower it completely out of the way most rudders will sit on the skeg  clear of the cup.  You will then be able to just about get at the cup through the weed hatch.  A pressure washer into the cup might work.    Then you can have a look at the bottom end of the stock.

 

N

 

[Bobbybass]

58 minutes ago, Mike Adams said:

Are you sure the sure the bottom bearing isn't being hit against the ground by changing water levels or wash from other boats. That could push it upwards making it tight or it could be filling up with silt. Impossible to say without seeing it.

Thank you.

 

It's tight all the time...never eases unless I physically lift the rudder up.

Pretty sure the cup is full of silt...or this calcious deposit that forms on my boat.

 

Now I have an idea of how the cup/rudder looks...I can get in the water and give it a damn good scraping.

 

Thank you all.!

 

Bob

47 minutes ago, Alan de Enfield said:

as a child I did have a good collection of Golliwog badges after sending off the labels to the manufacturer)

Careful old chap !..  ?

 

?

[Slim]

I've had nightmares regarding the bottom cup over the years. (different symptoms/story) . If you grasp the tiller bar at the end and push down/pull up can you get any movement in the rudder assembly? What type of top bearing do you have? If a ball race or taper bearing type are you sure that the bearing is free and not breaking up. Can you undo the top bearing casting (if that type) to discount it being the top bearing. Overall I would go for top bearing or pin out of cup before silt buildup.   

 

 

Edited June 13, 2020 by Slim
re read original post

[Tracy D'arth]

I'm still puzzled as to why the "cup" was ever designed facing up where it collects all the grit and mud rather than downwards.

 

I have made many bottom bearings the other way up with a phosphor bronze sleeve, they last much longer, in fact some are now 18 years old and have not worn at all.

[WotEver]

14 minutes ago, Tracy D'arth said:

I'm still puzzled as to why the "cup" was ever designed facing up where it collects all the grit and mud rather than downwards.

Laziness?  It's easier to weld a cup sat on the skeg than it is to weld a stub onto the skeg and a cup facing downwards on the bottom of the rudder shaft.

[Tracy D'arth]

1 minute ago, WotEver said:

Laziness?  It's easier to weld a cup sat on the skeg than it is to weld a stub onto the skeg and a cup facing downwards on the bottom of the rudder shaft.

Probably but why continue the error?  My bearings are only 35mm in diameter, easy to weld on but I have to ensure everything is in line as there is no slop in the bearing to accommodate poor workmanship. 

[Iain_S]

9 hours ago, Tracy D'arth said:

I'm still puzzled as to why the "cup" was ever designed facing up where it collects all the grit and mud rather than downwards.

 

I have made many bottom bearings the other way up with a phosphor bronze sleeve, they last much longer, in fact some are now 18 years old and have not worn at all.

On most narrowboats, if the "cup" faced fownwards, the rudder and stock would fall out. Few top bearigs provide vertical support.

[Tracy D'arth]

2 minutes ago, Iain_S said:

On most narrowboats, if the "cup" faced fownwards, the rudder and stock would fall out. Few top bearigs provide vertical support.

Sorry, I can't follow that, none that I have done have ever "fallen out". I cannot see the difference to which you seem to prescribe. The rudder weight is still take by the skeg.

[WotEver]

37 minutes ago, Iain_S said:

On most narrowboats, if the "cup" faced fownwards, the rudder and stock would fall out. Few top bearigs provide vertical support.

eh?

 

It's the same as 'standard' just the cup and pin swapped.  How could it 'fall out'?

[Cheshire cat]

Not sure if this will help or not . Has it ever behaved as expected. Our tiller is fine except it seizes up over the winter. It's a simple bronze bush and giving it a dousing in three in one oil and leaving it for a while does the trick. 

[Tracy D'arth]

Those stainless sleeve and nylon bearings used by some builders can seize with lack of use because the nylon expands when it absorbs water.

Edited June 13, 2020 by Tracy D'arth