More stuffing box questions

[BobnLesley]

Hi folks, further to my original query :
http://www.ybw.com/forums/showthread.php?t=316731&highlight=stuffing+box
We’ve now got the boat ashore and the stuffing box removed, stripped down and clean/free-moving, but before re-assembly I’d like to get some advice from those who know more about them than me – so that’ll be just about everybody!

1.The actual stuffing box part has space between the end and the treaded part which screws onto the main body for three wraps of tape/rope. However, when I took it apart there were four coils in there, the rearmost one sitting within the treaded section; I can see that this would give you a greater ‘sealing’ surface, at the expense of less adjustment being available, but is it good practice, bad practice, or doesn’t much matter one way or the other?

2. Grease – Is there a ‘special’ type that should be used? The unit’s main body, connections to and first inch or so of the pipe to the remote greaser were badly choked with a hard, creamy-coloured sludge; is this due to the ‘wrong’ grease being used, or just par for the course? There must’ve been some grease getting through as I’ve been diligently turning the remote greasers handle (it was a bit stiff to operate) at regular intervals.

As always, any and all feedback will be much appreciated.

Bob.

 

[Tranona]

3 rings should be enough. You really don't need grease, particularly if you are using PTFE packing, although the stern tube may have a beraing in the end which does need grease. Waterproof grease such as used in waterpumps is used. The ginge you have is grese with a little bit of seawater in it, nothing unusual.

Good opportunity while you have it apart to consider junking all that stuff and fitting a modern seal!

 

[ex-Gladys]

Dunno about (1), but (2) don't just use any old waterproof grease IMHO... I use Ramonol (thick creamy gunge - to quote you) which pushes into the stuffing box and lasts much better....

 

[Skysail]

+1 for Ramonol, though I am never sure the grease reaches the packing anyway

The 4th ring may have been added later to help seal the box once the first three had been compressed tightly.

 

[cimo]

Ramonol. lovely stuff.

 

[Bilgediver]

Hi folks, further to my original query :
http://www.ybw.com/forums/showthread.php?t=316731&highlight=stuffing+box
We’ve now got the boat ashore and the stuffing box removed, stripped down and clean/free-moving, but before re-assembly I’d like to get some advice from those who know more about them than me – so that’ll be just about everybody!

1.The actual stuffing box part has space between the end and the treaded part which screws onto the main body for three wraps of tape/rope. However, when I took it apart there were four coils in there, the rearmost one sitting within the treaded section; I can see that this would give you a greater ‘sealing’ surface, at the expense of less adjustment being available, but is it good practice, bad practice, or doesn’t much matter one way or the other?

As always, any and all feedback will be much appreciated.

Bob.

There must be an ability to tighten down the threaded sleeve in case of leakage and if this sleeve is threaded to the end this will require there be packing in the threaded part of the gland so the sleeve can continue to be screwed in to compress the packing,

 

[cimo]

on second read........

you didn't make mention of a compression ring Bob?
I'm wondering is it missing? - perhaps the 4th piece of packing was put in to compensate.

 

[pappaecho]

You need to measure the distance drom the edge of the shaft to the edge of the stuffing box cavity. This will be the thickness of the packing.
The fourth packing ring may be put in because the packing was not the right thickness.

 

[rotrax]

While it is in bits, as another poster said, it might be the time to look at a modern seal. If your tube/shaft dimensions are suitable, my favourite is the Volvo seal. Our last two boats were fitted with them-perfect. On our previous boat, to match a metric tube with an imperial shaft I had a s/s sleeve turned up which was epoxied on the tube, so bringing the dimension up.It was also a little overlength so as to move the sealing area away from the slight groove worn onto the shaft by the old style stuffing box packing. It is worth a thought, no more greasing or adjusting,and a dry bilge-at least as far as leaks from the shaft go.