Leaking stern gland issue

[Guest]

 

I think you're probably right. I've looked at the Vetus installation instructions and they don't show the commonly adopted canal boat method of plumbing them in from the weedhatch. They show a raw water scoop/skin fitting method and another method using raw water cooled engine water. So the weedhatch method is an adaptation.

 

I've taken the tube off the gland while the boat is stationary and water comes in from the gland. However, I've no idea which way around the water would flow while the boat is moving. I think this method of installation mainly relies on immersion of the gland and the relatively slow speeds of canal boats compared to other craft.

 

However, I don't think anyone's "raving" about water lubricated glands are they? I've never heard anyone raving about greasy glands either for that matter. They both work well enough and the water lubricated glands have been around long enough to know that the doom and gloom merchants who slagged them off initially were wrong. There are pros and cons of both water cooled and greasy glands. Having had a water cooled gland on my boat for over 9 years I wouldn't go back to a greasy gland, but that's just a personal preference.

 

I have a R&D coupling on mine - no problems as long as it's adjusted properly along with the engine mounts.

Yes I think I recall discussing the R&D thing with you before, Mike. It is one of those things that even Vetus dealers seem split on. The (Vetus) guy who fitted our engine swears it is better to have one fitted, whilst one well known local Vetus dealer says it is wrong to fit one! I won't be removing the R&D (or the Vetus gland) after ten years of reliable use. Perhaps if I was starting from scratch I might consider "conventional" but the shell was Vetused when I bought it. Vetus (Mitsubishi) engine is good apart from a couple of niggling problems with the cooling system; I dislike the gearbox fitted.

Edited April 30, 2014 by Guest

[blackrose]

Yes I think I recall discussing the R&D thing with you before, Mike. It is one of those things that even Vetus dealers seem split on. The (Vetus) guy who fitted our engine swears it is better to have one fitted, whilst one well known local Vetus dealer says it is wrong to fit one! I won't be removing the R&D (or the Vetus gland) after ten years of reliable use. Perhaps if I was starting from scratch I might consider "conventional" but the shell was Vetused when I bought it. Vetus (Mitsubishi) engine is good apart from a couple of niggling problems with the cooling system; I dislike the gearbox fitted.

 

I think the official Vetus line is that there should only be a single flexible point along the shaft (in this case the water lubricated gland). But perhaps they have in mind couplings that are a bit more flexible than the R&D coupling - which doesn't seem that flexible really.

[Guest]

 

I think the official Vetus line is that there should only be a single flexible point along the shaft (in this case the water lubricated gland). But perhaps they have in mind couplings that are a bit more flexible than the R&D coupling - which doesn't seem that flexible really.

Yes, an R&D is still indexed (think that's the correct term) to the gearbox coupling, and I think that is why they seem OK. I have seen Liverpool shells both with and without an R&D fitted on a Vetus setup. Member DOR has done a superb job of his Vetus setup. Hopefully he will comment on this thread.

[JohnDean]

I had this reply back from Vetus...

 

It is possible – but not advisable. You would need to separate the shaft from the gearbox coupling and have enough room behind the prop to give you a 2” gap. If you are quick – then you can slide the old cartridge off and get the new one on. Not a job for the faint hearted.

 

I'm inclined to think that they're just covering their backs really. From the replies here, the amount of water coming in with the seal removed isn't that alarming. I'm inclined to just be prepared with an extra pump and just get on with it. It can't take more than a couple of minutes to swap the seal over. Is that the conclusion that anyone else comes to?

[RLWP]

I'd only add that, in my experience, a couple of minute jobs that involve water coming in have a nasty habit of going wrong

 

Clean the shaft well, and do a trial run of fitting the new seal over the shaft before you remove the old one

 

And have a change of clothes handy

 

Richard

[Neil2]

I had this reply back from Vetus...

 

It is possible – but not advisable. You would need to separate the shaft from the gearbox coupling and have enough room behind the prop to give you a 2” gap. If you are quick – then you can slide the old cartridge off and get the new one on. Not a job for the faint hearted.

 

I'm inclined to think that they're just covering their backs really. From the replies here, the amount of water coming in with the seal removed isn't that alarming. I'm inclined to just be prepared with an extra pump and just get on with it. It can't take more than a couple of minutes to swap the seal over. Is that the conclusion that anyone else comes to?

I've seen it done on a sea going boat and it was scary. Not 100% sure it was a Vetus type though, someone said 1 litre a minute, if this boat had been left a minute it would have sunk.

[bizzard]

I've seen it done on a sea going boat and it was scary. Not 100% sure it was a Vetus type though, someone said 1 litre a minute, if this boat had been left a minute it would have sunk.

Probably badly worn with salt and sand. The few I've done only let in a trickle. Mind you some of these were W/beams that only shuttled back and forth to the pump out.

[Tony Brooks]

If the shaft has a keyway cut into it wrap the shaft in insulating or masking tape to protect the seal's lip from the shaft edges of the keyway. Also ensure the very end of the shaft has a chamfer on it to aid pushing eh seal over it.

[blackrose]

Probably badly worn with salt and sand. The few I've done only let in a trickle. Mind you some of these were W/beams that only shuttled back and forth to the pump out.

Mine's never let in a drop apart from when I've been servicing it. Still on the original seals after 9 years and plenty of miles (on a widebeam)

[JohnDean]

All noted and taken on board. Good point about protecting the seal by covering any keyway and also doing a trial fit before removing the old one.

I imagine that a sea going boat is likely to have the stern tube a lot further below the waterline. If that's the case, the pressure would go up in proportion to the depth so on a big boat that could be significantly more than on a canal boat.

 

I sent Vetus the pictures and indicated that I'm an Engineer and that prompted a more positive response as follows....

 

That is definitely one our ZWB bearings – looks bigger than a 25mm shaft. Most wide beams use 35mm.

With the boat standing still – there shouldn’t be any water coming in through the water feed tube. If you open the hatch; you should (if it’s been installed correctly) see the water level below the skin fitting.

 

The cassette slides off once the three Allen headed cap screws are removed (not the top greasing one):

http://www.vetus-shop.com/replacement-dual-lip-seal-for-vetus-zwb35-p-2549.html

 

You have an R&D ‘half split’ shaft coupling – which will be easy to slacken off. The shaft will need to slide back enough to slip the old seal out and the new one in with its gasket. I would clean and grease the shaft with some silicone grease first.

Once the front cassette is removed – there is no seal between the shaft and the stern tube – so water will gush in through the flutes in the bronze housing. A combination of a rag stuffed in and your Rulemate 750 switched to manual should cope.

 

Please note; I am not encouraging/advising you to do this yourself with the boat in. It’s really a job for a marine engineer. Out of the water you’ll have no problems.

 

That's a lot more encouraging, and is more in line with what I was thinking. It's clear that the bearing is designed to pass water so their comment about stuffing rag into the gap makes sense while it's off. It certainly sounds like it's going to be more than a trickle though.

 

Can I ask Bizzard if the ones you've done have been of this type and while in the water?

[Guest]

I know it has been mentioned already, but at least one Vetus dealer changes the seal afloat, and stops the majority of water by tying a greased rag between the prop and the stern tube (obviously working through weed hatch.) Never done this job yet, but if I did it afloat, this would be my plan of attack. If water can be kept from the cutlass bearing, it seems unlikely that much water will enter the boat. The slots in the cutlass are only small.

[cereal tiller]

I know it has been mentioned already, but at least one Vetus dealer changes the seal afloat, and stops the majority of water by tying a greased rag between the prop and the stern tube (obviously working through weed hatch.) Never done this job yet, but if I did it afloat, this would be my plan of attack. If water can be kept from the cutlass bearing, it seems unlikely that much water will enter the boat. The slots in the cutlass are only small.

Slight pedant alert Stan

 

It is a CutLESS bearing,not a large Knifey thing wielded by Pirates.

 

CT

[Guest]

Slight pedant alert Stan

 

It is a CutLESS bearing,not a large Knifey thing wielded by Pirates.

 

CT

Well done, I wondered who would be the first to notice that

Whilst I like Linux software, it is terrible at spelling

[bizzard]

All noted and taken on board. Good point about protecting the seal by covering any keyway and also doing a trial fit before removing the old one.

I imagine that a sea going boat is likely to have the stern tube a lot further below the waterline. If that's the case, the pressure would go up in proportion to the depth so on a big boat that could be significantly more than on a canal boat.

 

I sent Vetus the pictures and indicated that I'm an Engineer and that prompted a more positive response as follows....

 

That is definitely one our ZWB bearings – looks bigger than a 25mm shaft. Most wide beams use 35mm.

With the boat standing still – there shouldn’t be any water coming in through the water feed tube. If you open the hatch; you should (if it’s been installed correctly) see the water level below the skin fitting.

 

The cassette slides off once the three Allen headed cap screws are removed (not the top greasing one):

http://www.vetus-shop.com/replacement-dual-lip-seal-for-vetus-zwb35-p-2549.html

 

You have an R&D ‘half split’ shaft coupling – which will be easy to slacken off. The shaft will need to slide back enough to slip the old seal out and the new one in with its gasket. I would clean and grease the shaft with some silicone grease first.

Once the front cassette is removed – there is no seal between the shaft and the stern tube – so water will gush in through the flutes in the bronze housing. A combination of a rag stuffed in and your Rulemate 750 switched to manual should cope.

 

Please note; I am not encouraging/advising you to do this yourself with the boat in. It’s really a job for a marine engineer. Out of the water you’ll have no problems.

 

That's a lot more encouraging, and is more in line with what I was thinking. It's clear that the bearing is designed to pass water so their comment about stuffing rag into the gap makes sense while it's off. It certainly sounds like it's going to be more than a trickle though.

 

Can I ask Bizzard if the ones you've done have been of this type and while in the water?

They were and once the seal unit was withdrawn only trickles of water came in. However yes wrap a cloth around the shaft between the propeller boss and stern post but I wouldn't use a greasy one which if any grease gets up into the rubber bearing sleeve might perish or make it swell up. Not sure if the rubber used is completely impervious to oil and grease. And make sure the bilge pump works.

[Neil2]

.................I imagine that a sea going boat is likely to have the stern tube a lot further below the waterline. If that's the case, the pressure would go up in proportion to the depth so on a big boat that could be significantly more than on a canal boat.....................

 

Good point, and so obvious I'm ashamed I didn't think of it.

[Paul C]

Slight pedant alert Stan

 

It is a CutLESS bearing,not a large Knifey thing wielded by Pirates.

 

CT

 

Cutless is a brand name for one particular manufacturer's bearing (Duramax), while Cutlass has, over time, become the generic term for these types of bearing from all manufacturers.

[Guest]

They were and once the seal unit was withdrawn only trickles of water came in. However yes wrap a cloth around the shaft between the propeller boss and stern post but I wouldn't use a greasy one which if any grease gets up into the rubber bearing sleeve might perish or make it swell up. Not sure if the rubber used is completely impervious to oil and grease. And make sure the bilge pump works.

Good point re the grease, probably safest to use silicone grease for the vetus item?

[cereal tiller]

 

Cutless is a brand name for one particular manufacturer's bearing (Duramax), while Cutlass has, over time, become the generic term for these types of bearing from all manufacturers.

Thanks,perhaps i should inform the local Pirates?

 

Would be rather embarassing if they tried to board a Portugese Man o' War brandishing short brass tubes with neoprene inserts?

 

CT

[kevinl]

I've seen this done and it does work, open the weedhatch and put heavy duty plastic bag over the prop and tie it tight on the prop shaft, slip knot in a piece of rope, it doesn't stop all the water but it certainly cuts it down a lot. It'll be the only time you'll be glad to have a cement sack round you prop so make the most of it.

K

[Guest]

I've seen this done and it does work, open the weedhatch and put heavy duty plastic bag over the prop and tie it tight on the prop shaft, slip knot in a piece of rope, it doesn't stop all the water but it certainly cuts it down a lot. It'll be the only time you'll be glad to have a cement sack round you prop so make the most of it.

K

That sounds like a neat solution. Wonder if a cable tie would work around the tube?

[valrene9600]

I had this reply back from Vetus...

 

It is possible – but not advisable. You would need to separate the shaft from the gearbox coupling and have enough room behind the prop to give you a 2” gap. If you are quick – then you can slide the old cartridge off and get the new one on. Not a job for the faint hearted.

 

I'm inclined to think that they're just covering their backs really. From the replies here, the amount of water coming in with the seal removed isn't that alarming. I'm inclined to just be prepared with an extra pump and just get on with it. It can't take more than a couple of minutes to swap the seal over. Is that the conclusion that anyone else comes to?

Kings Lock change the Vetus seal in the water.

 

I have changed one by having the new one ready. Did not use rag around prop or any other trick but agree any help this way is good. Not much water came in or at least nothing to worry about.

 

WARNING; In the new seal kit there is an assembly piece. It is like a piece of split plastic tube. It goes inside the new seal and as you pass the assembly along the shaft it prevents any sharp nicks on the shaft cutting the seal. This assembly piece adjusts for different size shafts.

 

The tape idea is good but some of the nicks in shaft could cut through the tape. The bad nicks are usually where the shaft connects into the gearbox.

 

If you get nervous about water coming in and sinking the boat, it won`t, just find a shallow piece of canal and grond the stern. A little bit of reassurance for you.

Also use a little plastic syringe like you get from vets to give a pet medicine to push the grease in the alan key hole.

[Guest]

Kings Lock change the Vetus seal in the water.

 

I have changed one by having the new one ready. Did not use rag around prop or any other trick but agree any help this way is good. Not much water came in or at least nothing to worry about.

 

WARNING; In the new seal kit there is an assembly piece. It is like a piece of split plastic tube. It goes inside the new seal and as you pass the assembly along the shaft it prevents any sharp nicks on the shaft cutting the seal. This assembly piece adjusts for different size shafts.

 

The tape idea is good but some of the nicks in shaft could cut through the tape. The bad nicks are usually where the shaft connects into the gearbox.

 

If you get nervous about water coming in and sinking the boat, it won`t, just find a shallow piece of canal and grond the stern. A little bit of reassurance for you.

Also use a little plastic syringe like you get from vets to give a pet medicine to push the grease in the alan key hole.

I too use a syringe for the greasing. Works a treat.

[ditchcrawler]

I've seen this done and it does work, open the weedhatch and put heavy duty plastic bag over the prop and tie it tight on the prop shaft, slip knot in a piece of rope, it doesn't stop all the water but it certainly cuts it down a lot. It'll be the only time you'll be glad to have a cement sack round you prop so make the most of it.

K

Surly you need to tie it round the gland, not the shaft ?

[JohnDean]

Kings Lock change the Vetus seal in the water.

 

I have changed one by having the new one ready. Did not use rag around prop or any other trick but agree any help this way is good. Not much water came in or at least nothing to worry about.

 

WARNING; In the new seal kit there is an assembly piece. It is like a piece of split plastic tube. It goes inside the new seal and as you pass the assembly along the shaft it prevents any sharp nicks on the shaft cutting the seal. This assembly piece adjusts for different size shafts.

 

The tape idea is good but some of the nicks in shaft could cut through the tape. The bad nicks are usually where the shaft connects into the gearbox.

 

If you get nervous about water coming in and sinking the boat, it won`t, just find a shallow piece of canal and grond the stern. A little bit of reassurance for you.

Also use a little plastic syringe like you get from vets to give a pet medicine to push the grease in the alan key hole.

Many thanks, that's most reassuring.

[JohnDean]

Ok, after much thought and all your good advice I can now report that the job has been done and it was very easy indeed and not at all alarming.

The 'Cassette' with the two seals in it was bought from Vetus for just over £100 delivered which wasn't too expensive. It's the 35mm size for this boat, that's the size they normally fit to wide boats by all accounts. It was out of stock but took less than a week to arrive.

The flexible engine coupling is of a type that doesn't use a key, it relies on friction alone on the plain shaft.

The four bolts were slackened and I managed to twist the propeller shaft out of it with a bit of effort. I was expecting that to be much more difficult. With hindsight, I should have slackened the four bolts that go to the flexible cross element of the coupling too, it would have made life easier. I only discovered this when I couldn't easily re-insert the shaft. It started easily enough, but there's obviously a slight misalignment else it would have gone on as easily as it did with those up tight.

The propeller shaft have clearly been cut to length with some kind of disc grinder, and the edges were razor sharp. I rounded them off with a file and emery paper until they were nice and smooth. A trial of the new seal on the shaft showed how easy it was to get on so there was nothing for it but to have a go.

The instructions mentioned an assembly sleeve, but that hasn't been included in the kits of this size at least for some time. I've fed this back to Vetus. Since there's no key on this installation, it wouldn't have been needed anyway.

After taking off the three Allen Cap screws on the old seal and breaking the seal, there was very little water indeed escaping. You could have left if for an hour and it wouldn't have been a problem. A cup full every minute at the most.

I'd already greased the shaft with the grease supplied and put the bulk of the tube in between the two seals. They say fill it to about 50%, and that's about all the grease you get anyway, it's not a big tube. I kept a little back to add later but I need to get another tube really.

Slipping the old one off and putting the new one on was very quick and easy. There's an 'O' ring instead of a gasket on this size, but the 'O' rings is about the same diameter as half way down the taper of the mating face. It wasn't clear how to line that up really. I greased it and inserted it into the fixed part of the stern tube and it seemed to stay in the middle. Whether there's a proper register for it is hard to tell, I couldn't get close enough to get a look. Anyway, offering up the cartridge with just a gentle pressure was enough to completely stop the water so I presumed the 'O' ring was located correctly.

That all tightened up with the three Allen Cap screws and now there's no sign of a leak.

Now I've got the old one home, I can see that it hasn't got the slightest hint of grease on it, so I can only assume that it was installed without any. It's no wonder it failed!

Anyway, all's well that ends well, and I thought it only fair to report back and to pass on what I learned. This isn't a scary job at all, and you shouldn't be spooked by any of the doom and gloom merchants who think there's going to be a Tsunami when you remove the seal. (other stern tube designs may differ!)