Colecraft stern gland

[Peter-Bullfinch]

I have had my boat for nine years now and at the end of each day one turn of the greaser has stopped any drips.

Lately it has dripped more and so the time has come to tighten the gland. I maybe should have been doing this regularly but I didn't want to disturb what seemed to be working well.

It seems the fitting size needs a spanner of around 70mm or about 2 and three quarter inches. I have a sturdy plumbers pliers and a Stilson which should fit.

What in your experience is the best way to tackle this?

Edited September 2, 2015 by Peter-Bullfinch

[MtB]

Hmmm. I've never seen a stern gland like that.

 

I'd imagine one just tightens the big nut as you say (after loosening that locknut). It won't, or shouldn't be tight or difficult to move. A pair of pipe grips I'd expect to be fine.

 

But I doubt this has ever been done in the boat's history, given the location of that greaser tube, bang in the way. That will, I suspect, have to come off first.

Edited September 2, 2015 by Mike the Boilerman

[dor]

It might be my crooked eyesight, but does the shaft coming out of the plummer block on the left look out of alignment with the stern gland?

 

Tightening the gland might help, but it sounds as though it could do with repacking.

[Scholar Gypsy]

Wd it be a good idea to ask the mods to move this to the maintenance etc forum? I can't quite work how many separate bits there are, and which ones are meant to come undone. eg is the one on the right meant to be moved or not??

[FadeToScarlet]

Moved

[MtB]

It might be my crooked eyesight, but does the shaft coming out of the plummer block on the left look out of alignment with the stern gland?

 

 

It looks too crooked to be real, I thought. So prolly just something odd about the photography.

 

 

Tightening the gland might help, but it sounds as though it could do with repacking.

 

 

Why?

 

I'd have though if it's never been tightened in nine years, tightening it was all that was needed!

Moved

 

 

Just for the record, moving it while I was typing a reply caused my reply to vanish into the ether!

[dor]

Why?

 

I'd have though if it's never been tightened in nine years, tightening it was all that was needed!

Fair comment, but in my albeit limited experience of packed stern glands, when they are not tightened occasionally the packing goes very hard and tightening is not as effective as replacing with new packing.

[bigste]

That shaft does look way out but it must be a quirk of the camera because it could not work like that. I think tightening it will only be a temporary solution if it's not been done before. Probably end up repacking it.

[system 4-50]

I have had my boat for nine years now and at the end of each day one turn of the greaser has stopped any drips.

Lately it has dripped more and so the time has come to tighten the gland. I maybe should have been doing this regularly but I didn't want to disturb what seemed to be working well.

It seems the fitting size needs a spanner of around 70mm or about 2 and three quarter inches. I have a sturdy plumbers pliers and a Stilson which should fit.

What in your experience is the best way to tackle this?

Is it that the boat is 9 years old or that you have had it for 9 years?

[Peter-Bullfinch]

Thanks for all your help. The boat is almost 30 years old and spent the first 20 moored in Audlem. We are effectively it's second owners. I think it's a photographic quirk concerning the shaft alignment. There is a large lorry type shaft running from the engine room via two universal joints. The shaft at the stern gland doesn't run warm.

So..Take off the stern greaser tube..hold the big nut...slacken off the lock nut..tighten the large nut...Lock up...cross fingers?

[Tony Brooks]

While turning the shaft by hand until you feel the packing start to grip the shaft. Lock up lock nut, Then run and keep feeling the gland. It may get warm but should not get hot. If it does slacken the gland slightly.

[Bee]

Funny looking thing, looks like something out of a plumbers box of bits. Seriously though, I would be a bit careful with it, not too sure where the packing is held but it must work ok as its been there for so long. Careful not to tighten it too much as it might just get hot enough for the `nut` to pick up on the shaft and spin with it for a second or two till it unwinds or winds up tight, unlikely but things do happen.

[Tony Brooks]

Funny looking thing, looks like something out of a plumbers box of bits. Seriously though, I would be a bit careful with it, not too sure where the packing is held but it must work ok as its been there for so long. Careful not to tighten it too much as it might just get hot enough for the `nut` to pick up on the shaft and spin with it for a second or two till it unwinds or winds up tight, unlikely but things do happen.

 

That type of gland was very common on wooden and GRP cruisers and probably still is. The packing may be back up inside the large nut or there may be a pusher under the nut with the packing inside the tube like the two stud glands found on many narrowboats. There are also similar types that need a C spanner to adjust. I can not recall a nut ever coming undone once it had been properly locked up with the locknut.

[bizzard]

 

That type of gland was very common on wooden and GRP cruisers and probably still is. The packing may be back up inside the large nut or there may be a pusher under the nut with the packing inside the tube like the two stud glands found on many narrowboats. There are also similar types that need a C spanner to adjust. I can not recall a nut ever coming undone once it had been properly locked up with the locknut.

Stuart Turner was a maker of that type of stern tube and gland, they also made alignment adjustable stern tube shaft logs.

[MtB]

Funny looking thing, looks like something out of a plumbers box of bits. Seriously though, I would be a bit careful with it, not too sure where the packing is held but it must work ok as its been there for so long. Careful not to tighten it too much as it might just get hot enough for the `nut` to pick up on the shaft and spin with it for a second or two till it unwinds or winds up tight, unlikely but things do happen.

 

 

With a clockwise engine (as most are), if the locking nut comes undone, propshaft rotation it will tend to loosen the big nut rather than tighten it.

 

Except in astern obviously!

[Cavalier Jon]

I have the same setup in my Eggbridge boat. I'd be really keen to find out how you got on with it. Is the locknut the one nearest the gearbox?

[Tony Brooks]

I have the same setup in my Eggbridge boat. I'd be really keen to find out how you got on with it. Is the locknut the one nearest the gearbox?

 

No, its the thin hexagon nearest the propeller. The hexagon nearest the gearbox is part of a sleevenut. The packing might be inside the sleeve part or the sleevenut might bear on a pusher with the packing down inside the tube like with the two stud type.

[Cavalier Jon]

I think it's the other way round. The propeller-side nut, the thinner one, won't budge without loosening the thicker one. The thinner one is attached to the sleeve. I've given it a few clockwise turns now, so I'll see if the grease holds better when I cruise it this morning.

Edited September 17, 2015 by Cavalier Jon

[Tony Brooks]

OK, have it your way but consider this.

 

The body of the gland has thread all the way up. the threaded portion of both nuts must fit OVER the threaded body of the gland but to push on the packing there has to be a flange with a hole in it the same size as the shaft diameter. That portion of the nut will not fit onto the thread so it has to be located at the engine end of the threaded gland body. Any lock nut will then have to be to the propeller side of the main nut.

 

The only way the thin nut could act on the gland packing is if the gland body were slotted with a pusher extending through the slots. This design that I have never seen would leak through the slots.

[Cavalier Jon]

Ah yes, right I think I get it now. Thanks for helping me understand.

[Peter-Bullfinch]

Finally did the job. The packing had almost disappeared but talking to the previous owner it hasn't been touched since 1986. Presumably the plummer block kept everything steady with little flex. The packing used, three turns each sliced at an angle, was quarter inch.

Many thank Tony and others. We followed all your advice. The job was done with the boat in the water and nothing seeped in while we worked.

We are now back to the occasional drip so I'm pleased. This forum working at its very best!

[ditchcrawler]

Finally did the job. The packing had almost disappeared but talking to the previous owner it hasn't been touched since 1986. Presumably the plummer block kept everything steady with little flex. The packing used, three turns each sliced at an angle, was quarter inch.

Many thank Tony and others. We followed all your advice. The job was done with the boat in the water and nothing seeped in while we worked.

We are now back to the occasional drip so I'm pleased. This forum working at its very best!

Thanks for coming back and the photo