ghostlymoron
Well-Known Member
How tight should you do up your stern gland? Can this only be done on the water by number of drips.
Stern gland
- Thread starter ghostlymoron
- Start date
S
Skyva_2
Guest
Try turning it a half turn at a time and seeing the effect. You can run the engine in gear on the mooring if you are well tied up!
One or two drips per minute worked for us. The gland must not run hot.
see here also:
http://www.diybob.com/diyPackingGland.htm
But if you can, fit a Volvo seal! Happiness is a dry bilge....
One or two drips per minute worked for us. The gland must not run hot.
see here also:
http://www.diybob.com/diyPackingGland.htm
But if you can, fit a Volvo seal! Happiness is a dry bilge....
Caer Urfa
Well-Known Member
Why not fit a grease nipple and greaser?
I run all the time with my stuffing box/shaft tube full of grease, after a trip of say 5 hrs engine running I just give one turn on the greaser and thats it.
One tip! fit clear greaseing tube so you can see grease going down (not black tube)
When you first fill, pump grease till it comes out the stern gland/tube, then you know your shaft is full, and before you ask no it does not come out the other end where the stuffing box is.
Usualy after fitting new stuffing rings if it runs hot I need to adjust by turning locking screw back about 10min of a clock.
'No leaks at all'. stuffing box runs warm, done it for years.
I change stuffing rings every 4 years (approx 300 hrs)
Regards
Mike
I run all the time with my stuffing box/shaft tube full of grease, after a trip of say 5 hrs engine running I just give one turn on the greaser and thats it.
One tip! fit clear greaseing tube so you can see grease going down (not black tube)
When you first fill, pump grease till it comes out the stern gland/tube, then you know your shaft is full, and before you ask no it does not come out the other end where the stuffing box is.
Usualy after fitting new stuffing rings if it runs hot I need to adjust by turning locking screw back about 10min of a clock.
'No leaks at all'. stuffing box runs warm, done it for years.
I change stuffing rings every 4 years (approx 300 hrs)
Regards
Mike
Refueler
Well-Known Member
Most gland type are fitted with greasers - otherwise packing will scorch.
The drip is advised so that water actually cools the packing as well. With most glands and yours is same as mine - running it so no drips at all is not advised. It is too easy to over-tighten.
I use grease to seal it when moored, accepting drips when in use. That way packing lasts, shaft / gland doesn't run hot etc.
The drip is advised so that water actually cools the packing as well. With most glands and yours is same as mine - running it so no drips at all is not advised. It is too easy to over-tighten.
I use grease to seal it when moored, accepting drips when in use. That way packing lasts, shaft / gland doesn't run hot etc.
Richard10002
Well-Known Member
[ QUOTE ]
How tight should you do up your stern gland? Can this only be done on the water by number of drips.
[/ QUOTE ]
You can only tell it is right in the water.
I usually run my engine in gear whilst tied to the quay and check the drips. With a couple of breasts and springs, you wont go anywhere. Also make sure it is dripping every so often during a trip of more than a few hours.
You cant be precise, but 3 or 4 drips a minute seems to work for me. The gland is warm to the touch when running, but not hot.
How tight should you do up your stern gland? Can this only be done on the water by number of drips.
[/ QUOTE ]
You can only tell it is right in the water.
I usually run my engine in gear whilst tied to the quay and check the drips. With a couple of breasts and springs, you wont go anywhere. Also make sure it is dripping every so often during a trip of more than a few hours.
You cant be precise, but 3 or 4 drips a minute seems to work for me. The gland is warm to the touch when running, but not hot.
dovekie
Well-Known Member
Interesting and informative - for me at least. I ran mine (in ignorance) with no drips for 15 years. Perhaps 1000 to 2000 hours motoring all told. And when the shaft was replaced after that, there was wear on the shaft at the gland of a mm or so. I never repacked it either. It never leaked. I must confess I dont know if it was running hot. It has a grease line which was used regularly.
smeaks
Well-Known Member
hi have bilge envy, Jorvic's aint quite as clean
TigaWave
Well-Known Member
Many run with no grease (but not so many on UK boats) the water is a good lubricant and coolant, grease does not conduct heat very effectively.
Be aware that excessive use of grease can work its way aft to the stern tube bearing, this can block the water channels and cause it to run hot, wearing the bearing quite rapidly.
Be aware that excessive use of grease can work its way aft to the stern tube bearing, this can block the water channels and cause it to run hot, wearing the bearing quite rapidly.
cliffordpope
Well-Known Member
The drips can't be for cooling - 2-3 drips per minute wouldn't cool anything. Surely the point is that that rate of dripping is a useful tell-tale that the gland is not too tight, which would otherwise overheat and wear excessively?
To see how much water is needed for cooling, look at the other end. It runs surrounded by water, yet still there are often slots to guide a flow of water through the bearing. More than 3 drops per minute, I think!
To see how much water is needed for cooling, look at the other end. It runs surrounded by water, yet still there are often slots to guide a flow of water through the bearing. More than 3 drops per minute, I think!
Refueler
Well-Known Member
[ QUOTE ]
The drips can't be for cooling - 2-3 drips per minute wouldn't cool anything. Surely the point is that that rate of dripping is a useful tell-tale that the gland is not too tight, which would otherwise overheat and wear excessively?
To see how much water is needed for cooling, look at the other end. It runs surrounded by water, yet still there are often slots to guide a flow of water through the bearing. More than 3 drops per minute, I think!
[/ QUOTE ]
I was told many years ago by a yard engineer that the water being a reasonble amount entering the shaft tube, then small amount passing through as drips gives a "film" of water round the shaft with the grease ... the two combined prevent overheating and scoring of the shaft / gland.
All I know is when the removed my old shaft to replace bearers / shaft / coupling etc. when coupling was seized etc. The shaft was without groove indicating that above was true. I've seen many shafts grooved by overenthusiastic use of gland nut.... with apperance of scorching as well.
The drips can't be for cooling - 2-3 drips per minute wouldn't cool anything. Surely the point is that that rate of dripping is a useful tell-tale that the gland is not too tight, which would otherwise overheat and wear excessively?
To see how much water is needed for cooling, look at the other end. It runs surrounded by water, yet still there are often slots to guide a flow of water through the bearing. More than 3 drops per minute, I think!
[/ QUOTE ]
I was told many years ago by a yard engineer that the water being a reasonble amount entering the shaft tube, then small amount passing through as drips gives a "film" of water round the shaft with the grease ... the two combined prevent overheating and scoring of the shaft / gland.
All I know is when the removed my old shaft to replace bearers / shaft / coupling etc. when coupling was seized etc. The shaft was without groove indicating that above was true. I've seen many shafts grooved by overenthusiastic use of gland nut.... with apperance of scorching as well.
cliffordpope
Well-Known Member
I'm not arguing that over-tightening the nut can't cause over-heating - that's obvious. I'm querying whether 2-3 drops per minute can actually be the agent for carrying the heat away, and that its existence is merely confirmation that the nut is NOT overtightened, therefore not overheating in the first place.
It's a sign that there is no heating, not the reason for it.
It's a sign that there is no heating, not the reason for it.
Refueler
Well-Known Member
[ QUOTE ]
I'm not arguing that over-tightening the nut can't cause over-heating - that's obvious. I'm querying whether 2-3 drops per minute can actually be the agent for carrying the heat away, and that its existence is merely confirmation that the nut is NOT overtightened, therefore not overheating in the first place.
It's a sign that there is no heating, not the reason for it.
[/ QUOTE ]
Can't argue with that ... /forums/images/graemlins/grin.gif
I think the eng'r was highlighting that a 'film' of water allied with the grease was the agent ... and the drips showed that all was functioning correctly.
I'm not arguing that over-tightening the nut can't cause over-heating - that's obvious. I'm querying whether 2-3 drops per minute can actually be the agent for carrying the heat away, and that its existence is merely confirmation that the nut is NOT overtightened, therefore not overheating in the first place.
It's a sign that there is no heating, not the reason for it.
[/ QUOTE ]
Can't argue with that ... /forums/images/graemlins/grin.gif
I think the eng'r was highlighting that a 'film' of water allied with the grease was the agent ... and the drips showed that all was functioning correctly.
