Leaking rudder stock - change lip seal whilst boat in the water?

[steved]

The rudder stock on my boat is leaking enough to set the bilge pump off every so often, it's Tides Marine setup with a lip seal as per photo's.
Once everything is removed from the stock it should be reasonably straight forward job to prise the old seal out, cut if off and insert the new seal.

Dare I change the seal whilst the boat is still in the water? Or do I go for a lift out / in (£500 ish) to replace a £30-40 seal?

What would you do?

 

[anoccasionalyachtsman]

Can you seal the steering compartment?

(I was once party to an expensive mistake involving a Titanic-style bulkhead and am consequently more cautious).

 

[simonfraser]

how is the rudder held up ?
and if it leaks now, where is the water line wrt to the seal, if above its gonna get messy
can you dry her out ?

 

[scottie]

How buoyant is your rudder and are any bushes and or suchlike items secured

Could you get a lift and hold

 

[pvb]

Dare I change the seal whilst the boat is still in the water? Or do I go for a lift out / in (£500 ish) to replace a £30-40 seal?

What would you do?

I'd wait until summer, when marinas have cheap lift-out offers, and get the boat out of the water to do the job. You could polish the hull and antifoul at the same time. Typical East Coast cost would be around £250 for lift/cradle/relaunch.

 

[Bajansailor]

How big is the boat - is she the motor yacht shown in your avatar?

Would it be feasible to assemble a small 'rent a mob' to stand on the bow to lift the stern enough to ensure that the bits you remove are above the waterline?
probably not, with your lockdown, and restrictions on people getting together.
Hence I think that pvb's suggestion above is probably better.
How often does the bilge pump 'kick in'? Eg every 5 minutes, every few hours, twice a day...... ?

 

[TernVI]

Many of those seals have a mild steel ring encased in rubber. Once the rust starts, it can all go quite wrong, quite quickly.

I cannot see any way around replacing the seal ASAP. I've seen boats with a bellows/gaiter around the shaft and the tubular partof the hull, instead of a lip seal.
Doesn't look like you could fit anything like that?
I've seen people take a rudder out afloat, getting it back in was beyond fraught.
Iassume the rudder stock runs in another bearing out of shot to the top?

Our boat has such a seal, but there is a half-bulkhead just in front, so worst case is about 50 litres, if the bung is in the limber hole at the bottom of the bulkhead.

 

[rogerthebodger]

I would get a rubber tube the I/D of the white rubber hull support long enough so it will extend above the water line.

Once removed the rudder operating tiller etc. This will stop any water rushig in and even if you have to remove it to remove the seal support it can be position to stop water ingress.

You can tale you time to replace he seal then reverse all the disassembly.

As said insure the lip seal has stainless steel spring and ensure you fit it so the spring is to the water.

 

[pvb]

I've seen people take a rudder out afloat, getting it back in was beyond fraught.
Iassume the rudder stock runs in another bearing out of shot to the top?

I wonder whether the rudder has positive buoyancy? It's a mobo, so the rudder volume will be quite small.

 

[rogerthebodger]

I wonder whether the rudder has positive buoyancy? It's a mobo, so the rudder volume will be quite small.

If it doe not have positive buoyancy the OP could sling a rope around the rudder to stop it falling out.

I would also check it there is a screw thread in the top of the rudder shaft if so an eye bolt could also hole it up in place

 

[pvb]

If it doe not have positive buoyancy the OP could sling a rope around the rudder to stop it falling out.

I think that might be a bit precarious, bearing in mind the rudder needs to be lowered to clear the top bearing, and then raised again. As it's a mobo, the rudder will be quite small.

 

[Bilgediver]

I think you already have a spare split rudder post bearing sitting under the upper bearing carrier. It looks like it might have been installed incorrectly as the installation tool above it looks like it is upside down and moreover serves no further purpose other than being in the way. Might be worth giving Tideway a call and getting a copy of their procedure if not already on board.

 

[steved]

Thanks for all your input.

Bit more info about the boat, 41' single screw motor boat, rudder sits into a good sized skeg, so won't go anywhere once everything has been removed from the top.

Whilst there will obviously be water ingress once the old seal is removed, but at what flow is unknown, the water would be contained within the lazarette area with its own bilge pump. The actual shaft housing (not dissimilar to a cutlass bearing) will help in stemming the flow to a degree I guess.

I have thought about waiting till later in the year for cheaper lift out or lift and hold, but I'm one of those people that when you know you've got a leak like to get it sorted out.

The boat is 13 years old, and I'm pretty sure everything is original, and fitted correctly.

Probably only need to raise the stern by 6'' to be above the water line.



Steve

 

[rogerthebodger]

I think that might be a bit precarious, bearing in mind the rudder needs to be lowered to clear the top bearing, and then raised again. As it's a mobo, the rudder will be quite small.

2 running bowlines around the rudder from each side would hold the rudder quite firmly.

If it did fall through the rudder would not be lost

 

[pvb]

I think you already have a spare split rudder post bearing sitting under the upper bearing carrier. It looks like it might have been installed incorrectly as the installation tool above it looks like it is upside down and moreover serves no further purpose other than being in the way. Might be worth giving Tideway a call and getting a copy of their procedure if not already on board.

Tides Marine say "Before installing the rudder, insert the red installation hat into the lip seal. When rudder is in place, remove, invert and replace it on top of the Type-D unit to keep debris off the lip seal during use."

 

[rogerthebodger]

Thanks for all your input.

Bit more info about the boat, 41' single screw motor boat, rudder sits into a good sized skeg, so won't go anywhere once everything has been removed from the top.

Whilst there will obviously be water ingress once the old seal is removed, but at what flow is unknown, the water would be contained within the lazarette area with its own bilge pump. The actual shaft housing (not dissimilar to a cutlass bearing) will help in stemming the flow to a degree I guess.

I have thought about waiting till later in the year for cheaper lift out or lift and hold, but I'm one of those people that when you know you've got a leak like to get it sorted out.

The boat is 13 years old, and I'm pretty sure everything is original, and fitted correctly.

Probably only need to raise the stern by 6'' to be above the water line.

View attachment 108477

Steve

Hire the local rugby team to load the bow and lift the stern

 

[pvb]

Thanks for all your input.

Bit more info about the boat, 41' single screw motor boat, rudder sits into a good sized skeg, so won't go anywhere once everything has been removed from the top.


View attachment 108477

It would have been helpful if you'd put that info and photo in your original post...

 

[Tranona]

Not much different from replacing stern gland packing when in the water. Not much water will come in and you can always stuff a rag around the shaft to slow the inflow.

 

[Djad20]

[QUOTE = "Tranona, message: 7545872, membre: 28716"]
Ce n'est pas très différent du remplacement de la garniture de la glande arrière lorsque vous êtes dans l'eau. Il n'y aura pas beaucoup d'eau et vous pouvez toujours bourrer un chiffon autour du puits pour ralentir l'afflux.
[/CITATION]
I completely agree with your proposal to put a cloth to stop the water Gushing