Stern gland
Posted: Wed Jan 21, 2009 8:33 pmFrom: nswsailor (Original Message) Sent: 08/12/2007 01:24
Dear All; HELP!
I am in the throws of removing my inboard engine so that I can get to the bilge, my fresh water line and to do a realinement of the engine to shaft.. I noticed that the nut (48mm) on my stern gland was loose.
The question is, how tight should this nut be done up. If my thinking is right this nut regulates how tight the stern gland should be.
I am still in the water so cannot afford to make any mistakes!! I have inserted a photo to show the stern gland.
Phillip
SEAKA
---------------------------------------
Reply
Recommend Delete Message 2 of 6 in Discussion
From: fullandby Sent: 29/03/2008 04:30
Hello Phillip,
You have probably found the answer by now, or sunk. But in case you haven't, I had a stern gland like this on a previous boat. The nut closest to the engine needs to be tight enough so that you get a drop every 30 seconds or so when the shaft is turning, the gland relies on this water flow to keep it cool. When the shaft is still, a drop every few minutes is tolerable. This nut compresses the packing making it tighter to the shaft. If it is too tight no water can get through and the gland over heats. It can also score the shaft. If you tighten it and it still leaks too much, you need to repack it - best done out of the water. On my stern gland there was a second narrow nut further from the engine which was a locking nut to stop the nut closest to the engine unwinding ( not a desirable thing). In the picture you posted it looks as though this locking nut is well away from the packing nut, instead of locking it. I also tried to keep the whole assembly greased to stop it corroding, so I could tighten it easily when needed - it was in a hard to reach spot
Bart
--------------------------------------
Reply
Recommend Delete Message 3 of 6 in Discussion
From: nswsailor Sent: 30/03/2008 03:51
Bart,
Yes thats about the same conclusion I came to also, seems as though there is a tube over the packing which is locked by that nut at the rear. Will not know what's really going on until I next come out. As you say best done out of water! The small tube on top of my gland is the grease supply and I do keep that well supplied. Have not yet got the drip rate right, but will achieve that over next couple of weeks. Thanks for the post.
Phillip
SEAKA
------------------------------
Reply
Recommend Delete Message 4 of 6 in Discussion
From: Rob Sent: 30/03/2008 14:17
Hi Philip
If you are going to be out of the water to do the work with the engine out, it might be worth your while to have the stern gland re-packed if you find that the packing nut needs to be tightened too much. This job could be much easier to do without the engine in the way! I've put off doing it myself for a few years, but have to keep tightening the nut every now and then when it begins to drip too fast.
Cheers
Rob
Isabella II Pittwater
----------------------------
Reply
Recommend Delete Message 5 of 6 in Discussion
From: nswsailor Sent: 30/03/2008 21:02
Rob,
You are too late, I have just returned the engine and realigned the b***** thing.
I have two jobs, including the gland, requiring a small child, and both will be done when I next haul out.
Phillip
SEAKA
--------------------------------
Reply
Recommend Delete Message 6 of 6 in Discussion
From: shaun_--_ Sent: 06/11/2008 19:14
Alan Lucas did an article on gland packing in Cruising Helmsman Nov 2008
Dear All; HELP!
I am in the throws of removing my inboard engine so that I can get to the bilge, my fresh water line and to do a realinement of the engine to shaft.. I noticed that the nut (48mm) on my stern gland was loose.
The question is, how tight should this nut be done up. If my thinking is right this nut regulates how tight the stern gland should be.
I am still in the water so cannot afford to make any mistakes!! I have inserted a photo to show the stern gland.
Phillip
SEAKA
---------------------------------------
Reply
Recommend Delete Message 2 of 6 in Discussion
From: fullandby Sent: 29/03/2008 04:30
Hello Phillip,
You have probably found the answer by now, or sunk. But in case you haven't, I had a stern gland like this on a previous boat. The nut closest to the engine needs to be tight enough so that you get a drop every 30 seconds or so when the shaft is turning, the gland relies on this water flow to keep it cool. When the shaft is still, a drop every few minutes is tolerable. This nut compresses the packing making it tighter to the shaft. If it is too tight no water can get through and the gland over heats. It can also score the shaft. If you tighten it and it still leaks too much, you need to repack it - best done out of the water. On my stern gland there was a second narrow nut further from the engine which was a locking nut to stop the nut closest to the engine unwinding ( not a desirable thing). In the picture you posted it looks as though this locking nut is well away from the packing nut, instead of locking it. I also tried to keep the whole assembly greased to stop it corroding, so I could tighten it easily when needed - it was in a hard to reach spot
Bart
--------------------------------------
Reply
Recommend Delete Message 3 of 6 in Discussion
From: nswsailor Sent: 30/03/2008 03:51
Bart,
Yes thats about the same conclusion I came to also, seems as though there is a tube over the packing which is locked by that nut at the rear. Will not know what's really going on until I next come out. As you say best done out of water! The small tube on top of my gland is the grease supply and I do keep that well supplied. Have not yet got the drip rate right, but will achieve that over next couple of weeks. Thanks for the post.
Phillip
SEAKA
------------------------------
Reply
Recommend Delete Message 4 of 6 in Discussion
From: Rob Sent: 30/03/2008 14:17
Hi Philip
If you are going to be out of the water to do the work with the engine out, it might be worth your while to have the stern gland re-packed if you find that the packing nut needs to be tightened too much. This job could be much easier to do without the engine in the way! I've put off doing it myself for a few years, but have to keep tightening the nut every now and then when it begins to drip too fast.
Cheers
Rob
Isabella II Pittwater
----------------------------
Reply
Recommend Delete Message 5 of 6 in Discussion
From: nswsailor Sent: 30/03/2008 21:02
Rob,
You are too late, I have just returned the engine and realigned the b***** thing.
I have two jobs, including the gland, requiring a small child, and both will be done when I next haul out.
Phillip
SEAKA
--------------------------------
Reply
Recommend Delete Message 6 of 6 in Discussion
From: shaun_--_ Sent: 06/11/2008 19:14
Alan Lucas did an article on gland packing in Cruising Helmsman Nov 2008