Vibrating tiller

[RufusR]

Hi all

 

Catching up with boat maintenance ahead of cruising season so a little help again if I may . I get tiller shake at about 800-1000 rpm . Checked weed hatch and cleared any debris , still does it . Reliably informed tiller has not come out of stays as it steers fine just vibrates .

 

Before I call engineer out any thoughts on what you else could be ?

 

Ps I have an anti cavitation plate fitted on bottom of weed hatch

[Guest]

RufusR, on 26 Feb 2016 - 1:17 PM, said:RufusR, on 26 Feb 2016 - 1:17 PM, said:

Hi all

 

Catching up with boat maintenance ahead of cruising season so a little help again if I may . I get tiller shake at about 800-1000 rpm . Checked weed hatch and cleared any debris , still does it . Reliably informed tiller has not come out of stays as it steers fine just vibrates .

 

Before I call engineer out any thoughts on what you else could be ?

 

Ps I have an anti cavitation plate fitted on bottom of weed hatch

 

Have you felt (looked at if you can see it if the water is clear enough) the prop for any obvious damage eg bent or damaged blade??

Edited February 26, 2016 by MJG

[RufusR]

Looks ok from what I can see but that's why I was looking at calling engineer , thought I would check to see if could be something simple as that would be out of water job that check properly and fix . Would it be worse across the revs if it to was s warped prop though ?

[mrsmelly]

Looks ok from what I can see but that's why I was looking at calling engineer , thought I would check to see if could be something simple as that would be out of water job that check properly and fix . Would it be worse across the revs if it to was s warped prop though ?

 

I had a damaged prop which I changed last month. Going forwards there was a slight vibration and the engine lost about 500 revs maximum because it was mishapen. In reverse it was horrendous and the engine tried to jump out of the boat. Even a slight bend to one blade could cause problems.

 

Tim

[Guest]

RufusR, on 26 Feb 2016 - 1:29 PM, said:

Looks ok from what I can see but that's why I was looking at calling engineer , thought I would check to see if could be something simple as that would be out of water job that check properly and fix . Would it be worse across the revs if it to was s warped prop though ?

 

I would say it would depend on the type of damage and how severe it is.

 

Another thing to check - Is the tiller a tight fit in the tube??

 

Can you move it much by lifting the tiller?

[RufusR]

I had a damaged prop which I changed last month. Going forwards there was a slight vibration and the engine lost about 500 revs maximum because it was mishapen. In reverse it was horrendous and the engine tried to jump out of the boat. Even a slight bend to one blade could cause problems.

 

Tim

It's fine in reverse just forward at 800 revs but could be slight bend I guess ! Oh Lordy sounds expensive

[zenataomm]

It could be a natural harmonic which lets itself known at that rpm.

or

A clipped or damaged blade.

or

A damaged skeg through clipping a cill or underwater object or bad docking, if skeg is slightly off centre it can cause rudder vibration.

or

If your skeg has a vertical support bracket between it and the uxter plate between the prop and rudder that could get warped if the weight of the boat has sat on the skeg at some time.

or

If the swim is short and your counter not deep then air may get sucked down at a certain speed causing turbulence.

 

I would get someone to walk along the towpath and watch what happens a few feet forward of the back to see if there are eddies and swirling which might be sucking down air. Then you can start eliminating options ...... to tell any engineer you're thinking of involving.

[valrene9600]

Is it possible to put cavitation plate back wrong way. Mine is attached to hatch cover but not sure if poss to put back wrong way round. Just a thought.

Is the rudder bearing in good condition. Can tiller be moved back and forward a lot in which case bearing might be worn or breaking up causing judder. On mine bearing is visable and easily changed.

Edited February 26, 2016 by valrene9600

[RufusR]

I would say it would depend on the type of damage and how severe it is.

 

Another thing to check - Is the tiller a tight fit in the tube??

 

Can you move it much by lifting the tiller?

Will check again seems ok but worth another look

[mrsmelly]

It's fine in reverse just forward at 800 revs but could be slight bend I guess ! Oh Lordy sounds expensive

 

Mine cost me about 600 squid including the prop. I could have claimed on my insurance but decided against the hassle. The boat is vastly better now.

 

Tim

[RufusR]

It could be a natural harmonic which lets itself known at that rpm.

or

A clipped or damaged blade.

or

A damaged skeg through clipping a cill or underwater object or bad docking, if skeg is slightly off centre it can cause rudder vibration.

or

If your skeg has a vertical support bracket between it and the uxter plate between the prop and rudder that could get warped if the weight of the boat has sat on the skeg at some time.

or

If the swim is short and your counter not deep then air may get sucked down at a certain speed causing turbulence.

 

I would get someone to walk along the towpath and watch what happens a few feet forward of the back to see if there are eddies and swirling which might be sucking down air. Then you can start eliminating options ...... to tell any engineer you're thinking of involving.

Thanks all good things to check

[peterboat]

mine was a damaged prop only caused problems at low RPM, when it was out last year it went in for a repitch they also repaired all the damage since then it has been lovely. Only cost £80.00 pound for repitch and repair at Woodwards in Hull

[Bee]

Most likely cause is rudder shaft bearings, top, bottom or both, personally I would leave it until it became really annoying then bring forward a docking date and fix it then, I have Delrin top and bottom bushes, cheap and good, the old steel cup on the skeg is really not up to the job nowadays if that is what you have.

[RufusR]

mine was a damaged prop only caused problems at low RPM, when it was out last year it went in for a repitch they also repaired all the damage since then it has been lovely. Only cost £80.00 pound for repitch and repair at Woodwards in Hull

 

 

that seems very reasonable , did the boat need to come out to get the prop off though ?

Most likely cause is rudder shaft bearings, top, bottom or both, personally I would leave it until it became really annoying then bring forward a docking date and fix it then, I have Delrin top and bottom bushes, cheap and good, the old steel cup on the skeg is really not up to the job nowadays if that is what you have.

 

its pretty damn annoying now but if its a out the water job I might try and put up with it until early 2017 when blacking and BSS is due kill many birds with one stone so to speak

[haza]

hi i had a ribrating tiller last summer ...i took it into chirk marina ..were a very nice chap said i think it could do with the rubber flange replacing ..i said ok it took him about half maybe an hour ...at a cost of about £60 ...i had been putting up with this problem for a while thinking it was going to cost hell of a lot more ....its great now ...

[Dalslandia]

Is this vibes something that always been there or just lately?

[Timx]

_{I GET A SLIGHT VIBRATION THAT THE LAST OWNER TOLD ME IS NORMAL, FAIR ENOUGH BUT WHY ? AND SHOULD IT BE LOOKED AT ?}

[Dalslandia]

_{I GET A SLIGHT VIBRATION THAT THE LAST OWNER TOLD ME IS NORMAL, FAIR ENOUGH BUT WHY ? AND SHOULD IT BE LOOKED AT ?}

 

The wear and tear, with an airfoil instead of the normal plate it would not vibrate, a wrap around the LE to 60-70% of the chord, 5% Chord noose radius, (10% Diameter) max thickness at 20-25% chord and max thickness 20%-25% of the chord. With or without a fish tail 20-25% long and 7% total wide.

 

Balance area 17-20% of the total chord, so 1/5th in length

 

Turn rate will increase, course keeping improved, no bad vibes.

 

And even better with the noose offset 3% to meet the propeller stream, each way over and below the prop shaft.

 

Dalslandia's rudder was from birth, 850 and 1000 mm long, at bottom and top, 200 mm balance so 21.6%, and very heavy and vibrated, now a special Schilling design, 25% thick, 205 mm balance, and 840 mm long, 24.4% balance, 24% might have been perfect (850mm). at high power it can be a little heavy to get back center, hydraulic hand pump wheel, and 160 HP turning a 32" propeller.

Edited March 5, 2016 by Dalslandia

[dave moore]

Am I the only forum member to be baffled by the post above?

 

Dave

[Dalslandia]

Am I the only forum member to be baffled by the post above?

 

Dave

 

Mine post or the ONE ABOVE mine, no baffles needed but endplates help a lot.

[cuthound]

Tillers sometimes vibrate because of the shallowness of the canal. This effect is made worse if you try to go too fast.

 

However if your tiller is vibrating all of the time on a variety of canals, then it will not be because of the lack of depth.

 

Edited to add a missing worm.

Edited March 5, 2016 by cuthound

[WotEver]

Could be a worn cup? Worn bearings? Probably not much to worry about though

[twbm]

Oh It's technical.

 

I was hoping it was something Midland Chandlers and Anne Summers had collaborated on.

[RufusR]

Could be a worn cup? Worn bearings? Probably not much to worry about though

After further investigation this is what I think it is , definite signs of bearing wear . Engineer coming Thursday to look at it to confirm hopefully this is all it is and quote for repair .

 

 

Wtf is that huge super techy post all about further up ? No narrowboat is that blooming complicated that sounds like the plans for natos new nuclear narrowboat lol

[WotEver]

Wtf is that huge super techy post all about further up ? No narrowboat is that blooming complicated that sounds like the plans for natos new nuclear narrowboat lol

Ahh, Dalslandia - yep, he's pretty techy

Edited March 5, 2016 by WotEver