prop shaft seal
- Thread starter Jon
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dialtone
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I'm not an expert in this area: but yes. They do drip. However it should be just a drop every once in a while. Someone knowledgable in this area will chime in. Sometimes you can tighten but I've been told you DO WANT them to drip very slowly. I would say a drip every few seconds is too often but maybe a drip every 5-10 minutes is fine. Something to do with keeping the seal wet or something like that.
The Masons
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Yes, it is important that the dripping is not stopped completely as the water which comes up the stern tube lubricates the packing material in the stuffing box and reduces the inherent drag and wear on the prop shaft. A simple snugging of the locking nut should suffice. Here are generic instructions:
SHAFT PACKING GLAND (STUFFINGBOX):
A properly adjusted shaft packing gland should drip slightly (from 1 to 2 drops per minute) with the engine off. Too loose an adjustment will allow too much water in the bilge and engine operation will spray water from the shaft. Too tight an adjustment will rob the engine of power, and the lack of water lubrication in the packing gland can generate enough heat to damage the gland and/or score the propeller shaft.
ADJUSTMENT:
1. Hold the packing nut with one wrench, use a second wrench to loosen the lock nut. Turn the lock nut far enough to keep it from interfering with the next adjustment (2 or 3 turns.).
2. Tighten the packing nut to obtain 4 to 15 drops per minute. Hand tightening of the packing nut is often sufficient to obtain this adjustment. If this is not the case, an additional 1/4 to 1/2 turn with the wrench should produce the desired results.
3. Hold the packing nut in place with one wrench, and use the second wrench to bring the locking nut securely against the packing nut. Make certain that the locking nut is tight. Failure to do this could allow the packing nut to back off when the engine is operating.
4. Operate the engine at slow speeds in forward and reverse and use a light to check for excessive water at the packing nut. Shut off the engine and recheck packing for proper drip.
SHAFT PACKING GLAND (STUFFINGBOX):
A properly adjusted shaft packing gland should drip slightly (from 1 to 2 drops per minute) with the engine off. Too loose an adjustment will allow too much water in the bilge and engine operation will spray water from the shaft. Too tight an adjustment will rob the engine of power, and the lack of water lubrication in the packing gland can generate enough heat to damage the gland and/or score the propeller shaft.
ADJUSTMENT:
1. Hold the packing nut with one wrench, use a second wrench to loosen the lock nut. Turn the lock nut far enough to keep it from interfering with the next adjustment (2 or 3 turns.).
2. Tighten the packing nut to obtain 4 to 15 drops per minute. Hand tightening of the packing nut is often sufficient to obtain this adjustment. If this is not the case, an additional 1/4 to 1/2 turn with the wrench should produce the desired results.
3. Hold the packing nut in place with one wrench, and use the second wrench to bring the locking nut securely against the packing nut. Make certain that the locking nut is tight. Failure to do this could allow the packing nut to back off when the engine is operating.
4. Operate the engine at slow speeds in forward and reverse and use a light to check for excessive water at the packing nut. Shut off the engine and recheck packing for proper drip.
SGIDAVE
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Hello Jon,
The Masons have given a very good description of adjusting the packing gland or stuffing box.
To answer your question regarding "adjust" vs "replace," if you've not adjusted it yet then definitely try tightening it. If you've already tightened it as much as possible and it still leaks too much, then replacement of packing material is indicated.
This is ANOTHER application where an Infrared thermometer will help a lot. Its OK to tighten the packing gland but alas, how much? What if it's dripping 1-2/minute after you've tightened it? Should you go back and loosen it slightly to get 4 drops/min? If you can monitor the stuffing box temp and confirm that WITH USE (i.e., with the shaft running for a while) the temp is no more than 10º above sea temp then it's OK. Your stuffing box may be too tight if it gets warmer than that.
My point is that following the temp of the stuffing box is another objective measure of it's condition along with counting drops of water leaking past the packing.
So, get one of these and keep it handy.
Plus, they make GREAT cat toys...heck, our dogs chase the red dot too :lol:
Fair Winds and Cool Stuffing Boxes,
/dave
The Masons have given a very good description of adjusting the packing gland or stuffing box.
To answer your question regarding "adjust" vs "replace," if you've not adjusted it yet then definitely try tightening it. If you've already tightened it as much as possible and it still leaks too much, then replacement of packing material is indicated.
This is ANOTHER application where an Infrared thermometer will help a lot. Its OK to tighten the packing gland but alas, how much? What if it's dripping 1-2/minute after you've tightened it? Should you go back and loosen it slightly to get 4 drops/min? If you can monitor the stuffing box temp and confirm that WITH USE (i.e., with the shaft running for a while) the temp is no more than 10º above sea temp then it's OK. Your stuffing box may be too tight if it gets warmer than that.
My point is that following the temp of the stuffing box is another objective measure of it's condition along with counting drops of water leaking past the packing.
So, get one of these and keep it handy.
Plus, they make GREAT cat toys...heck, our dogs chase the red dot too :lol:
Fair Winds and Cool Stuffing Boxes,
/dave
So if there are no drips at all when engine at rest, this is a problem, right ?
I assume the outside water travels along the prop shaft under a small amount of pressure, or is it somehow drawn up along the shaft to provide lubrication. If it's pressure then it cannot be too high as the prop is not that far down below the stuffing box position.
I thought the stuffing box was fed with water via a hose as shown below...
I assume the outside water travels along the prop shaft under a small amount of pressure, or is it somehow drawn up along the shaft to provide lubrication. If it's pressure then it cannot be too high as the prop is not that far down below the stuffing box position.
I thought the stuffing box was fed with water via a hose as shown below...
knotflying
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Here is what I was told:
When the shaft is not turning you should not get a drip.
When it is turning you should get one drip about every 20 seconds
To check temperature while running get outside water temperature and then point laser on nut and temperature should be no hotter than 20 degrees
My experience has been a very slight turn ( like only 1/4 inch)reduces the drip substantially.
Additionally, remember that there is water being forced into the shaft by the hose off the exhaust elbow. At least that is the way the BY engine is.
When the shaft is not turning you should not get a drip.
When it is turning you should get one drip about every 20 seconds
To check temperature while running get outside water temperature and then point laser on nut and temperature should be no hotter than 20 degrees
My experience has been a very slight turn ( like only 1/4 inch)reduces the drip substantially.
Additionally, remember that there is water being forced into the shaft by the hose off the exhaust elbow. At least that is the way the BY engine is.
knotflying":1nvagu46 said:
So Mike.... how do we explain this 😱 I believe this is with the hose line disconnected and was posted some time ago by a fella who's brass barb for the hose got broken by an errant foot.... :roll:
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Closing the boat after a weekend cruise, I noticed our packing nut/stuffing box was dripping more than normal. The next day, I counted a drip rate of over 65 drips/minute - obviously WAY too much when the engine is off.
I asked Peter at WIYY to take a look at it. His assessment was that the packing was dry and should be replaced. However, he suggested that there is not enough room on the shaft to replace the packing, thereby necessitating removing the entire shaft. Obviously, this is a kick to the gut and potentially the end of our season.
Anyone else repack the flax in the packing nut on a R25 Classic? Is it possible to do without removing the shaft? Any advice would be greatly appreciated. Help!
I asked Peter at WIYY to take a look at it. His assessment was that the packing was dry and should be replaced. However, he suggested that there is not enough room on the shaft to replace the packing, thereby necessitating removing the entire shaft. Obviously, this is a kick to the gut and potentially the end of our season.
Anyone else repack the flax in the packing nut on a R25 Classic? Is it possible to do without removing the shaft? Any advice would be greatly appreciated. Help!
SGIDAVE
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swillmerchant":22eul3vh said:
Hello Doug and Jess,
HOW did Peter know the packing was "dry."
I would attempt TIGHTENING the stuffing box nut unless this has already been tried. Certainly, the packing material is a wear item and will eventually need replacing, HOWEVER, unless the stuffing box has been adjusted (properly tightened), jumping to replacement is premature.
I'm not the sharpest knife in the drawer, but I've never heard of removing the shaft to repack a stuffing box. Is Peter suggesting the gland be repacked then the shaft placed through? I must not understand his process. Normally the gland is repacked IN PLACE that is with the shaft through the gland. Putting the shaft through the gland AFTER you've repacked it...won't work (it would displace the new packing material).
Again, I probably don't understand what Peter meant about removing the shaft to facilitate repacking the gland.
Yikes!
/dave
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Not having seen the situation it is hard to second guess someone who has seen it and is experienced. My first thought would be to tighten down the packing nut. Then to also check the temperature as I stated in this thread. If that does not work then packing replacement would be required. Replacing the packing while the shaft is assembled is difficult. I can't recall how much space you have from the back of the nut to the transmission coupling, but you need room to get into the interior of the nut and clear out all the old packing. Quite frankly removing the shaft may be an easier and quicker method. I don't see why this should ruin the remainder of your season. Removal of the shaft is very easy and should take no longer than 45 minutes once the boat is out of the water. Actually you really only have to move it out enough to take off the shaft coupling and then you can slide the stuffing nut off. The new packing goes back in three pieces with the joints for each piece staggered as well as cut on a bias. You should be back in business in less than a day.
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baz":3so13ilr said:knotflying":3so13ilr said:
So Mike.... how do we explain this 😱 I believe this is with the hose line disconnected and was posted some time ago by a fella who's brass barb for the hose got broken by an errant foot.... :roll:
Baz,
The water is rushing out because at that point you are below the waterline. If the hose was connected and above the waterline it would not be gushing out like that.
swillmerchant
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Peter indicated there's no more room to tighten the nut. That's kinda what I thought looking at it, and partially why I didn't attempt it myself. Having helped repack a stuffing box on a 115' schooner at the dock, I know how much of a deluge it can be to replace the packing in the water. So, hauling it makes sense. Seeing that there's only 6" or so between the packing nut and the engine, I can imagine that it'd be a PITA to do so while the shaft is in position. So, I trust removing the prop is the right move too. I just had no idea how involved it would be. It just sounds extensive...and expensive.
If it's possible to do in less than a day, that certainly relieves some anxiety. I just don't know enough about it all to evaluate it without overreacting. I'll hopefully be able to talk to Peter some more today to evaluate our options. After putting only 25 hours on the engine during a busy summer for us, it was not what we were hoping to hear. Thanks for your input!
If it's possible to do in less than a day, that certainly relieves some anxiety. I just don't know enough about it all to evaluate it without overreacting. I'll hopefully be able to talk to Peter some more today to evaluate our options. After putting only 25 hours on the engine during a busy summer for us, it was not what we were hoping to hear. Thanks for your input!
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What year is the boat? Depending on how old it is I am surprised that it would be dried out so quickly. In any event, based on what you said in the last post, Peter is on the right track by removing the shaft. I have been involved with the packing being changed while on the shaft for an R-29 and there is even less room to slide the nut back and it was a PITA. Removing the shaft or slipping it back will probably save time in the long run. You may get enough room if you can pull the shaft back without removing the prop, but I don't recall how much space is between the rudder and the prop. You need enough room to put a socket and ratchet behind the shaft coupling to remove the bolt and then be able to slide the coupling off. You can then slide the nut off and clean out the old packing like a gentleman.
Good luck and let us know how it works out. I am sure if Peter can get to it you will be back on the water quickly.
Good luck and let us know how it works out. I am sure if Peter can get to it you will be back on the water quickly.
Levitation
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In your situation I would consider talking to the factory before spending money. The packing should be capable of being changed without pulling the shaft. I would suggest for the faint of heart that you do it in the slings. The rest of you can replace the packing and get your daily shower over with simultaneously :lol: Very efficient.
No propeller shaft should drip at rest - IMO.
Batteries are not infinite, stuff does happen, and a dripping stuffing box is an invitation to finding your boat sunk at the dock.
By the same token there should be some drip when turning to provide lubrication. It usually is a matter of turning the packing nut about an eighth of a turn to go between the two extremes. It is not rocket science as generations of sailors have managed to deal with it.
We went through this a year or so ago at the Florida gathering when someone read that part about 2 drips a minute, etc. and became concerned and fellas started fondling their nuts. We found that packing nuts that are years old and never touched can be a bear to break loose.
Roam has/had a ton of hours on her stuffing box without being tinkered with. Perhaps Rich will chime in with his perspective.
No propeller shaft should drip at rest - IMO.
Batteries are not infinite, stuff does happen, and a dripping stuffing box is an invitation to finding your boat sunk at the dock.
By the same token there should be some drip when turning to provide lubrication. It usually is a matter of turning the packing nut about an eighth of a turn to go between the two extremes. It is not rocket science as generations of sailors have managed to deal with it.
We went through this a year or so ago at the Florida gathering when someone read that part about 2 drips a minute, etc. and became concerned and fellas started fondling their nuts. We found that packing nuts that are years old and never touched can be a bear to break loose.
Roam has/had a ton of hours on her stuffing box without being tinkered with. Perhaps Rich will chime in with his perspective.
pugtug613
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I have replaced packing on a shaft. Not on my Ranger, but another boat. Remove the shaft? That sounds like way too much work. The hardest thing is finding the proper wrenches. You need 2 open end wrenches of the proper size. Then one turns and one stays still. Once you open up and move the nut, now you "dig" out the old stuffing with a pick or a hook type of tool. Have the new stuffing already cut to size. I use 3 wraps (3 separate pieces) and make sure the seem does not line up. You push each one in one at a time. Then reverse the nut thing. Water will come out when you dig out the stuffing (if your in the water). But, it's manageable. I can't think it's too much different on a Ranger.
Chester
Chester
gerlots
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If you are using a mechanical seal, then you need to remove the shaft. Or if for some reason you are using an unsplit seal then you need to remove the shaft. However if you use the packing described by the manufacturer, you do not need or would you want to remove the shaft.
R J Markus
S/C/E Engineer ( Retired)
R J Markus
S/C/E Engineer ( Retired)
knotflying
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Speaking from experience, I bet you I could replace the shaft seal faster by moving the shaft back and removing the nut then trying to do it while it is still on the shaft.
Posting in an old thread but had found the information in here quite helpful a few months back when dealing with our leaking propshaft.
We've had an issue with excessive water coming from the propshaft for some time now and the solution was always to tighten the adjustment/lock nuts until the dripping ceased at stop (with a sporadic drop when underway).
Late last year, got to the point where I was adjusting the nuts on every outing and in my frustration, ended up overtightening the lock nut and stripping the threads on the brass bolts (stainless steel nuts are stronger than brass bolt!)
Learned another lesson in the cost of boating and got replacement parts installed.
Went on the boat this morning and found that the prop shaft was leaking (more than just dripping) into the bilge and the bilge pump running (not sure how long it's been going).
We keep a piece of plastic (cut up 2L soda bottle) wrapped up around the prop shaft to prevent it from slinging salt water all over the engine compartment (little trick taught to us by our dealer LBYS).
Anyway, I noticed black stuff all over it and wondering if anyone has seen or knows what this might be... I'm thinking it might be burned up packing material?
After adjusting the nuts so that the prop shaft stopped gushing water into the bilge, we went on an hour cruise.
Got back to the slip and the prop shaft is gushing water again.
What am I doing wrong? Do I need to haul the boat out and replace the packing/stuffing?
Also, I've read different things both here and on the rest of the internet about how warm the parts around the prop are supposed to get with proper cooling with drips occuring sporadically... How hot would these parts need to get to burn up the packing material?
I didn't take a new picture but here's a photo I had shared with the factory when trying to find replacement hardware for the bolts/nuts. What temperature range would be "normal" for the parts in the photo (spinning brass part on left, silver prop shaft, greenish copper stuffing box)?:
Thanks in advance for any insights!
We've had an issue with excessive water coming from the propshaft for some time now and the solution was always to tighten the adjustment/lock nuts until the dripping ceased at stop (with a sporadic drop when underway).
Late last year, got to the point where I was adjusting the nuts on every outing and in my frustration, ended up overtightening the lock nut and stripping the threads on the brass bolts (stainless steel nuts are stronger than brass bolt!)
Learned another lesson in the cost of boating and got replacement parts installed.
Went on the boat this morning and found that the prop shaft was leaking (more than just dripping) into the bilge and the bilge pump running (not sure how long it's been going).
We keep a piece of plastic (cut up 2L soda bottle) wrapped up around the prop shaft to prevent it from slinging salt water all over the engine compartment (little trick taught to us by our dealer LBYS).
Anyway, I noticed black stuff all over it and wondering if anyone has seen or knows what this might be... I'm thinking it might be burned up packing material?
After adjusting the nuts so that the prop shaft stopped gushing water into the bilge, we went on an hour cruise.
Got back to the slip and the prop shaft is gushing water again.
What am I doing wrong? Do I need to haul the boat out and replace the packing/stuffing?
Also, I've read different things both here and on the rest of the internet about how warm the parts around the prop are supposed to get with proper cooling with drips occuring sporadically... How hot would these parts need to get to burn up the packing material?
I didn't take a new picture but here's a photo I had shared with the factory when trying to find replacement hardware for the bolts/nuts. What temperature range would be "normal" for the parts in the photo (spinning brass part on left, silver prop shaft, greenish copper stuffing box)?:
Thanks in advance for any insights!