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Repacking stern gland in water


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when I changed a vetus gland afloat I tied a bin bag around the shaft in the water which kept a lot of water back. I imagine a traditional stern gland would behave similarly. My friend repacked his afloat without any problems.

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Prepare packing

Pump gland full of grease

Switch on bilge pump

Remove plate and packing

Repack

Replace plate

Regrease

Turn off pump.

 

You will get some water in but not a lot.

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If there's still a tiny little bit of tightening (or a bit more if you didn't leave it until the very end) pump the greaser, then tighten the last bit to make a perfect sealing of the gland-packing, then you undo the nuts and/or bolts and remove the plate don't bother removing what still in the shaft and that's stopping the water from coming in, put in 1 or more rings of packing but leace enough space free to put the plate/packing pushing bush in and don't tighten too tight, job done.

 

For safety you can put someting underneath the shaft, but normally after the grease and the tightening of the last bit of old packing it shouldn't leak more than a drop.

 

Peter.

Edited by bargemast
  • Greenie 1
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When I did mine I packed as much grease onto the shaft via the greaser turning the shaft by hand. Loosened nuts etc, removed the old packing and inserted the pre cut new pieces. Having re fitted and tightened the nuts {finger tight] I Tightened the nuts two flats at a time alternately until the shaft was just free and not binding.......I found that the grease was enough to hold back the water, just make sure you squeeze in as much as you can whilst turning the shaft...............not one drop of water spilt.

  • Greenie 1
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When I did mine I packed as much grease onto the shaft via the greaser turning the shaft by hand. Loosened nuts etc, removed the old packing and inserted the pre cut new pieces. Having re fitted and tightened the nuts {finger tight] I Tightened the nuts two flats at a time alternately until the shaft was just free and not binding.......I found that the grease was enough to hold back the water, just make sure you squeeze in as much as you can whilst turning the shaft...............not one drop of water spilt.

 

My experience also, having done it a couple of times.

 

I anticipated lots of water would probably come in, but none did, even when last ring of old packing removed.

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As others have said, just don't take all (or even any) of the old stuff out, just add a few more rings, don't overtighten it, you risk wearing a groove in the shaft.

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If you have packed a stern gland before and are absolutely certain that you have all the bits needed then it's a simple job which you can do quite quickly and easily and let the bilge pump catch any drips.. Probably not a good plan for the first time you open up a stern gland for repacking.

 

You should have a bilge pump ready and working and enough grease to fill the stern tube to seal the water out and some of the right size of packing and the means of cutting it to length before you get spanners out.

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As others have said, just don't take all (or even any) of the old stuff out, just add a few more rings, don't overtighten it, you risk wearing a groove in the shaft.

 

Is a groove in the shaft a bad thing? I imagine it would be a highly polished surface, easily filled by the compressed sealing fibres, and only really reducing the effective diameter of the shaft by a gnat's cock!

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Hmmm! There's all kinds of practices out there.

 

Our shared boat has now done 20,000 hours. We have just had a new stern tube and propeller shaft. The shaft has a polished groove in it around 5mm deep. I'll try and get a photo of it. According to the guy who did the work the groove is caused by a combination of the packing being overtightened and the old packing not being removed before the new was inserted.He suggested that the packing goes hard over time and inevitably picks up grit which then grinds away the propshaft.

 

What is a suitable tool to get all of the old packing out?

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Hmmm! There's all kinds of practices out there.

 

Our shared boat has now done 20,000 hours. We have just had a new stern tube and propeller shaft. The shaft has a polished groove in it around 5mm deep. I'll try and get a photo of it. According to the guy who did the work the groove is caused by a combination of the packing being overtightened and the old packing not being removed before the new was inserted.He suggested that the packing goes hard over time and inevitably picks up grit which then grinds away the propshaft.

 

What is a suitable tool to get all of the old packing out?

One of those old fashioned bradawls (or was it a gimlett?) that joiners once used with a small screw thread on the end.

https://www.amazon.co.uk/Gimlet-4-5mm-Pack-1-U-G0475/dp/B001L5PF7G?ie=UTF8&*Version*=1&*entries*=0

Edited by Guest
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Hmmm! There's all kinds of practices out there.

 

Our shared boat has now done 20,000 hours. We have just had a new stern tube and propeller shaft. The shaft has a polished groove in it around 5mm deep. I'll try and get a photo of it. According to the guy who did the work the groove is caused by a combination of the packing being overtightened and the old packing not being removed before the new was inserted.He suggested that the packing goes hard over time and inevitably picks up grit which then grinds away the propshaft.

 

What is a suitable tool to get all of the old packing out?

 

Some folks advocate using a screw but I prefer one of these:

 

https://www.cromwell.co.uk/shop/adhesives-and-sealants/gland-packing/packing-extractors/f/8387

  • vct7264141v.jpg
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Is a groove in the shaft a bad thing? I imagine it would be a highly polished surface, easily filled by the compressed sealing fibres, and only really reducing the effective diameter of the shaft by a gnat's cock!

Surprising how much of a groove / step it can make, I think it probably makes it difficult to get a decent watertight seal on that area, never had that problem myself but the shaft on my boat is a scrap shaft (one of a pair) I picked up at Beaulieu boat jumble, it was about 2 metres long and had a couple of steps in it. I needed a longer shaft than normal, I managed to fit it so the unworn parts ran in the packing gland and the cutless bearing, it would have put a mighty dent in someones wallet to replace them so there must have been a good reason to take them out. Not a strength issue so I can only imagine it was the grooves.

Edited by Bee
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Surprising how much of a groove / step it can make, I think it probably makes it difficult to get a decent watertight seal on that area, never had that problem myself but the shaft on my boat is a scrap shaft (one of a pair) I picked up at Beaulieu boat jumble, it was about 2 metres long and had a couple of steps in it. I needed a longer shaft than normal, I managed to fit it so the unworn parts ran in the packing gland and the cutless bearing, it would have put a mighty dent in someones wallet to replace them so there must have been a good reason to take them out. Not a strength issue so I can only imagine it was the grooves.

 

Kick around boat yards long enough and you'll come across very, very worn propshafts. I have seen ones nearly half the original diameter

 

 

when I changed a vetus gland afloat I tied a bin bag around the shaft in the water which kept a lot of water back. I imagine a traditional stern gland would behave similarly. My friend repacked his afloat without any problems.

 

I did a Vetus seal recently, it was very undramatic. A bit more of a leak than from a conventional sterngland but far less than the deluge I was expecting. With the seal off I draped a bit of rag around the shaft so that the tiny flow of water dropped into the bilge rather than under the engine

 

Richard

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Kick around boat yards long enough and you'll come across very, very worn propshafts. I have seen ones nearly half the original diameter

 

 

 

I did a Vetus seal recently, it was very undramatic. A bit more of a leak than from a conventional sterngland but far less than the deluge I was expecting. With the seal off I draped a bit of rag around the shaft so that the tiny flow of water dropped into the bilge rather than under the engine

 

Richard

That was my finding too. I had read tales of gushing water and certain sinking should this type of seal fail, but TBH even without anything around the outer shaft, I believe the bilge pump would easily cope (mine did anyway!)

As an aside, I am not as keen on the new style Vetus seal and am trying a Radice seal this time.

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That was my finding too. I had read tales of gushing water and certain sinking should this type of seal fail, but TBH even without anything around the outer shaft, I believe the bilge pump would easily cope (mine did anyway!)

As an aside, I am not as keen on the new style Vetus seal and am trying a Radice seal this time.

 

The seal I fitted was supplied by the owner. From Simply Bearings

 

It looked like an ordinary double lip seal with a garter spring - very much what I would expect

 

Only at a fraction of the price of the Vetus item

 

Richard

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The seal I fitted was supplied by the owner. From Simply Bearings

 

It looked like an ordinary double lip seal with a garter spring - very much what I would expect

 

Only at a fraction of the price of the Vetus item

 

Richard

The one I fitted from Vetus was like that, but I found a nasty groove in the shaft in a very short time. It is a long story more here if you can be bothered http://destinynarrowboat.weebly.com/vetus.html. The old one had been in for a good few years and was the older style bonded in seal which looked more like a tiny gokart tyre.

Edited by Guest
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We managed to position the shaft in a different place in the gearbox coupling (a bit further forward), so the seal is working on a different part of the shaft. There was a groove, like you usually get with a lip seal on a soft shaft

 

That Radice seal looks interesting

 

Richard

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Hmmm! There's all kinds of practices out there.

 

Our shared boat has now done 20,000 hours. We have just had a new stern tube and propeller shaft. The shaft has a polished groove in it around 5mm deep. I'll try and get a photo of it. According to the guy who did the work the groove is caused by a combination of the packing being overtightened and the old packing not being removed before the new was inserted.He suggested that the packing goes hard over time and inevitably picks up grit which then grinds away the propshaft.

 

What is a suitable tool to get all of the old packing out?

 

That the packing goes hard over time, is surely due to having it much to much tightened, then it will overheat and burns the grease, becomes hard, and then it can create a groove.

 

I have added packing many times on my barges, lost count because of a lack of fingers as I've only got 2 hands laugh.png

 

Peter.

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We managed to position the shaft in a different place in the gearbox coupling (a bit further forward), so the seal is working on a different part of the shaft. There was a groove, like you usually get with a lip seal on a soft shaft

 

That Radice seal looks interesting

 

Richard

I was able to move the clamp coupling a little, enoguh to run on "new" shaft. Still it grooved in record time :(

The Radice is shorter so is running on fresh shaft again. Time will tell. I think it is just a modified Volvo type and they seem well liked.

I really like the look of the PSS seal which doesn't seal on the shaft, hence there should be no shaft wear. Maybe next time we drydock...

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I find it difficult to believe that our packing was tightened too much because rather than the typical two bolt pusher arrangement we had one where the pusher was tightened up using a C spanner.

 

post-4914-0-29208600-1463350921_thumb.jpg

 

The reason why we had the work done was because no matter how much packing we put in it still dripped every five seconds or so despite using lots of grease.

 

I like the bendy spring corkscrews. I think I'll have to get one. They must be easier to use than a woodscrew.

 

 

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