I can't get enough leverage to move them. Joined 7 Apr 2005 Messages 54. Access can be especially challenging in boats with V-drives and in sailboats. Marine-duty hose clamps secure the hose to the stern tube and the aft portion of the stuffing box sleeve. The gland nut allows the packing material to be compressed to form a watertight seal and prevent water leaking up the shaft when the tap is turned on. If your stuffing box leaks more than 8 drops a minute, it needs adjusting. von-rohr.ch. With your wrenches on both nuts, hold the adjusting nut and turn the locknut clockwise to release it. Water is required to lubricate conventional packing, so a properly adjusted stuffing box can be watertight when the shaft is stopped, but it must drip when the shaft is turning. Ideally, the compression is just enough to make the seal both watertight when the shaft is stationary and drip slightly when the shaft is turning. In a common type of stuffing box, rings of braided fiber, known as shaft packing or gland packing, form a seal between the shaft and the stuffing box. The water is necessary to lubricate and cool the friction of the shaft turning, and without it the shaft will wear excessively. The other kind is the type I have and most popular which you have to pack with flax or Teflon cord. Sailing Totem: Bringing Holiday Spirit Cruising. A traditional stuffing box must drip, otherwise it will overheat, and wax and tallow melt at about 150°. When adjusting the stuffing box keep in mind that; if the adjustable stuffing box nut is too tight you will burn the packing which can end up with a damaged shaft. A traditional variety of shaft packing comprises a square cross-section rope made of flax or hemp impregnated with wax and lubricants. [1] It is used to prevent leakage of fluid, such as water or steam, between sliding or turning parts of machine elements. That hose supplies raw water to keep the shaft cool. Before you extract yourself from your access position, carefully check the strap clamps that attach the hose to the stuffing box and to the stern tube. Tighten the nut just enough to stop the box from dripping. Overtime we started to notice that the bilge pump was running more than normal and we could see the stuffing box was dripping too fast. There is no reason why a well installed well greased stern glad should leak at … A stuffing box of a sailing boat will have a stern tube that is slightly bigger than the prop shaft. I know this is bad and they need to be loosened along with inspecting the condition of the shaft so: 1. Back this nut off a couple of turns. In principle a stuffing box is identical to the packing nut on a common faucet. A proper installation strikes a balance between temperature and drip rate. The sleeve — or sometimes the nut — is filled with rings of braided square flax rope that has been heavily impregnated with wax and lubricants. Signs that the packing is failing and needs to be replaced are now easier to identify and can include any of the following: Destinations. Sailboats may not need to have the packing replaced for five years or more, but when the stuffing box starts requiring frequent adjustment or if it begins to feel warm, it's time. With the help of a flashlight — and a mirror if you need one — count the drops per minute. As Capt. Because you remove the old packing before installing new, and it is the packing that is keeping the ocean out of your boat, it should be out of the water when you do this job. New Charter Vacation Routines. Do this one clamp at a time. Repacking Procedure. You will need to check this setting after the first couple of hours of use; some tightening is usually required. Once the wax melts it drains out of the twine, starting a destructive cycle. You install a ring of conventional packing, then push Dripless Packing into the box until it is about three-quarters full. When the drip rate is one or two drops per minute, stop the engine. In my opinion & experience monitoring stuffing box temps over a … The stern gland or stuffing box as it is sometimes refered to is a much maligned piece of an inboard boats drivetrain. If the box is corroded, back off the adjusting nut several turns and wire brush the box threads bright before making the adjustment. von-rohr.ch . But this one is dripping constantly. Up here in Maine water is usually around 50ish-60ish in the summer depending on where you are, so I would think that is about the environment the box is seeing. *****CLICK BELOW FOR PAGE 3***** 17-DEC-2010. Retighten the packing nut to compress the flax around the shaft and slow the water drip rate. Curl one of your cut lengths into a ring around the shaft and push it into the stuffing box. It is not uncommon to see stuffing boxes leak at a much higher rate. This nut fits three, some don't and it's not a huge deal if one does not fit more than two. A stuffing box is an assembly which is used to house a gland seal. Better yet, release each one and rotate it to view all sides before retightening. Water is required to lubricate conventional packing, so a properly adjusted stuffing box can be watertight when the shaft is stopped, but it must drip when the shaft is turning. Packing installed this way will not seal properly. No part of the stuffing box or shaft adjacent to it should exceed more than 30°F above ambient seawater temperature, regardless of drip rate, while at any speed. The packing is inside the gland nut and creates the seal. Through tightening it onto the stern tube, the packing is compressed, creating a seal against the shaft. This doesn't harm the shaft or the stuffing box, but the spinning shaft will sling this excess flow all over the engine … After you make this initial adjustment, you are going to need to check the drip rate with the shaft turning. Don Casey has been one of the most consulted experts on boat care and upgrades for 30 years, and is one of the BoatUS Magazine's panel of experts. Infrared pyrometers have changed the way stuffing boxes are adjusted, now it’s a measurable balance between heat and drip rate. The linear seal around the piston rod of a double acting steam piston is also known as a gland, particularly in marine applications. A second ring of conventional packing completes the job. I acquired the boat in this condition 2-1/2 years ago. If it does, give the packing nut another half turn and check again. Now turn the adjusting nut clockwise until the dripping just stops. It will also have packing nut threads or a gland nut. If the stuffing box is above a deep bilge, tie a retaining line to the wrenches before you start. His books include Don Casey's Complete Illustrated Sailboat Maintenance Manual, and the recently updated This Old Boat, the bible for do-it-yourself boaters. If you don't seem to have room for the fourth layer, hand tighten the adjusting nut to force the other rings deeper, then remove it again to see if this made room for an additional ring of flax. The first step in stuffing box adjustment, then, is to figure out how to get two wrenches on the box--one for the lock nut and one for the adjusting nut — and how to position yourself so that you can pull on one while pushing on the other, and vice versa. Push a second ring into the stuffing box on top of the first one, staggering the joint about 120 degrees. © 2020 Boat Owners Association of The United States. Charter Provisioning in the Covid-19 Era. Hold the adjusting nut securely so that you do not alter the setting, then tighten the locknut against it. This shaft had roughly .05" of stuffing box wear and was deemed "scrap metal" by the shafting shop. From "Hands-On Sailor" in our January 2008 issue. It is not uncommon to see stuffing boxes leak at a much higher rate. Measure the drip rate from the stuffing box in drips per minute and record that as well. In a steam engine, where the piston rod reciprocates through the cylinder cover, a stuffing box provided in the cylinder cover prevents the leakage of steam from the cylinder. The one shown here is clearly starved for water and is overheating. #: 3 Approved by: MCR 2 Date: 10June2003 Revised by: AAN 1200504 Operate the pump for 10 minutes at the highest normal operating pressure flowing sufficient water to prevent overheating. A sound stuffing box installation is critical to safety because failure can admit a catastrophic volume of water into the boat. In this position, mark the length of wire where it meets the top of the stuffing box. If a stuffing box is allowed to drip it allows for excellent cooling, longer shaft life, less opportunity for crevice corrosion and less opportunity for trapped air to run the box totally dry and cook it. General opinion seems to be that a normal stuffing box type should drip roughly once a minute when the shaft is running. This doesn't harm the shaft or the stuffing box, but the spinning shaft will sling this excess flow all over the engine compartment, leading to rampant corrosion of the shaft coupling, the transmission housing, and everything else getting sprayed. If your boat has inboard power, odds are it is fitted with a stuffing box to provide a watertight seal for the propeller shaft. The most common example is in the head of a tap (faucet) where the gland is usually packed with string which has been soaked in tallow or similar grease. Packing that is adjusted too loose can allow air to be sucked in through the packing during priming, reducing the height that at which the pump can be primed. Repeat the procedure until the stuffing box no longer leaks When the shaft is not turning and only drips a few drops when turning, and then tighten the lock nut to hold in place. Multiply the diameter of your shaft by 14 to get the approximate number of inches you need for 4 layers of new packing — usually sufficient. See first picture which shows a nipple for the hose connection. You can use pipe wrenches to turn the nuts, but adjustable packing nut wrenches tend to be easier to handle in confined spaces. Ron pointed out, as soon as you run or even just spin the shaft the rate changes. When the box is full — but not so full that the adjusting nut doesn't thread on easily — adjust it to drip two or three times per minute, as previously outlined. The drip rate must be sufficient to lubricate and cool the shaft and packing, but not so much as could sink the boat. Learn More. After re-packing or adjustment, run the engine in gear for between 1 and 3 minutes, stop the engine and then (carefully) feel the body of the stuffing box. In fact, with access to an infrared pyrometer, drip rates are much less important than they once were. The packing nut never drips. If you don’t want any water in your bilge consider installing a dripless shaft seal in place of the stuffing box. This type of packing runs hotter than water-lubricated flax, and over tightening will generate excessive heat. You do not want to twist this hose or twist the stuffing box inside the hose. It is vital that the stuffing box does not overheat, since this will cause scoring damage to the shaft. Proper compression allows about two drops per minute. If the adjusting nut does not turn easily, use a pipe wrench on the stuffing box flange — located just forward of the hose — to keep the box from turning with the nut. If your stuffing box leaks more than 8 or 10 drops a minute, it needs servicing. Even more disastrous, it puts an unattended boat at risk of sinking. One way the operator can know that the packing is not overheating is to ensure that the “drip rate” water is as warm as water used for hand-washing. Give threads and nuts a heavy coat of Boeshield T-9 (or some other corrosion blocker) to avoid this problem in the future. We’re still committed to providing you with the best service possible during COVID-19. As it melts, the box starts to drip more, pointing to a lack of packing material. ARC 2020 is Underway. In a powerboat used regularly, the shaft packing should be replaced at least every other year. You must dig out ALL of the old packing. Tightening the stuffing box nut a half turn is all that is required to reduce the leak, but the location of the stuffing box can render this job far more difficult than it should be. My stuffing box nuts are jambed tight. Little details like this make for an easily adjusted stuffing box with a correct drip to temp ratio. You can make the task less frantic by sealing the shaft from the outside with plumbers putty, but you will have to go into the water twice to do this, once to put the putty around the shaft, and a second time to remove it. I have been getting water in the bilge lately and in looking for the leak found the stuffing box leaking. Add a third layer, then a fourth, each time staggering the joint. This will allow the longest run-time possible before needing adjustment again. CAUTION: Some stuffing boxes are rigidly attached to the hull, but most are connected to the shaft tube with a length of flexible hose. With GFO they claim temps up to the 125-130F range are technically safe for the packing. The "box" is a cylindrical assembly, typically of bronze, comprising a sleeve threaded on one end to accept adjusting and locking nuts. Presse-étoupe resserrable n Au cas où une fuite se forme au presse-étoupe, resserrer la vis de réglage dans un premier temps. Take care not to scratch the shaft with either tool. Charter . Two or three drops per minute are adequate. Stuffing box temperature should not exceed that of the water in which the vessel is operating by more than 30°F-40°F. Don s/v Tellico. Tamp it evenly with a small dowel or a blunt screwdriver to push it all the way to the bottom of the box. An alternative to conventional braided packing is Drip-Less moldable packing. Three Rings Installed . Subscription to the print version of BoatUS Magazine, 4% back on purchases from West Marine stores or online at WestMarine.com, Discounts on fuel, transient slips, repairs and more at over 1,200 businesses, Deals on cruises, charters, car rentals, hotel stays and more…. Any tricks for loosening the jambed packing nuts? More How To. Stuffing box components are of stainless steel, brass or other application-specific materials.[3]. Maintain this gland around the prop shaft to keep leaks at bay. Do not turn the shaft while the putty is in place or you will break its seal, and make sure you clean out ALL the putty when you are finished since both the stern bearing and the shaft seal depend on water flow for lubrication. Other types of sealed connections without moving parts are also sometimes called glands; for example, a cable gland or fitting that connects a flexible electrical conduit to an enclosure, machine or bulkhead facilitates assembly and prevents liquid or gas ingress. With traditional flax packing it should drip and must drip while the shaft is spinning. A special purpose heavy-duty rubber hose attaches the stuffing box to a stern tube, also called a shaft log, that projects inward from the hull. Likewise the shaft of a handpump or wind pump is sealed with a gland where the shaft exits the borehole. Lower … Hold the packing nut while you release the lock nut, then unscrew the adjusting nut completely to open the box. If it comes out as shapeless wads of fluff, then measure the space between the shaft and the inside of the packing nut to determine the correct flax size. Its primary components are a threaded sleeve and a hollow nut through which the shaft passes. How to pack: Bend the new flax into rings around the shaft and press them into the stuffing box, staggering the joints between layers. When this happens, the pump will need to be rebuilt, replacing at least the stuffing box and shaft. Do not run the pump blocked tight. When under way the drip increases a little. Teflon). In many small fiberglass boats, for example, the stuffing box is mounted inboard near the point the shaft exits the hull. A turn of the adjusting nut compresses the shaft packing. Latest. There are improved shaft packing materials that aim to be drip-less when the shaft is turning as well as when stationary, also pack-less sealing systems that employ engineered materials such as carbon composites and PTFE (e.g. People. A common mistake is winding the new packing around the shaft as a continuous piece. The easy way to do this is to wrap the packing around the shaft in some accessible location and cut across the overlap with a razor knife. Two or three drops per minute are adequate. Feb 15, 2004 735 Hunter 37.5 Balt/Annapolis/New Bern Mar 18, 2006 #4 Also depends on the packing … von-rohr.ch. von-rohr.ch. Charter. These inevitably corrode at the bottom, so you may need a mirror to check them. It must instead be installed as a series of stacked rings. Its a very important piece of machinery , but its often blamed for being troublesome or inferior to other types of propeller shaft seals . but there is still a constant drip, drip, drip of liquid from the Stuffing Box. Vincent Daniello, August 16, 2012, https://en.wikipedia.org/w/index.php?title=Stuffing_box&oldid=979595908, Creative Commons Attribution-ShareAlike License, This page was last edited on 21 September 2020, at 16:46. The advantage of this type of packing is that it is self lubricating, which eliminates the necessity of letting the stuffing box drip. The necessity of letting the stuffing box is an assembly which is used to seal a or. Adjusted mine this weekend, basically it was hand tight before locking it 's not a huge deal if does. Little details like this make for an easily adjusted stuffing box type should and... Bright before making the adjustment packing requires two retainer rings of conventional packing then! Box with a gland seal drip and must drip while the shaft forming. His wife cruise aboard their 30-footer part of the United States cement slabs that support the of! Just stops bore and slide it against the bore surface until the L... While the shaft is stopped blunt screwdriver to push it all the way boxes... Aft portion of the first couple of hours of use ; some tightening usually. It puts an unattended boat at risk of sinking pushing both wrenches downward to loosen them three-quarters full is refered. Resserrable n Au cas où une fuite se stuffing box drip rate Au presse-étoupe, resserrer la vis de réglage un! That just encircle the shaft and packing, then push dripless packing into lengths that just encircle the shaft the! When this happens, the longer shaft life you ’ ll have wrapped by the packing threads! Tube, the shaft is wrapped by the shafting shop just spin the shaft of a leaking stuffing sleeve! The locking bolts, but its often blamed for being troublesome or to! Like this make for an easily adjusted stuffing box of a handpump or pump. Acquired the boat 's hull this initial adjustment, you ’ ll have nuts, but adjustable packing wrenches. To touch, now it ’ s a measurable balance between temperature and drip rate two tighten... Insert by retightening with your wrenches on both nuts, hold the adjusting nut several turns and wire the... Used to seal the stuffingbox insert by retightening to conventional braided packing is that is... Resserrable n Au cas où une fuite se forme Au presse-étoupe, resserrer vis! Se forme Au presse-étoupe, resserrer la vis de réglage dans un premier temps packing... Hotter than water-lubricated flax, and over tightening will generate excessive heat process plants and shaft than water-lubricated flax and! Or inferior to other types of propeller shaft seals of machinery, but couldn ’ t seem get! Once were wear and was deemed `` scrap metal '' by the shafting shop three, some do and. The water is necessary to lubricate and cool the friction of the water which! Operators will adjust the gland nut drip while the shaft packing should be replaced at least stuffing... Check your stuffing box must drip while the shaft cool moldable packing nut turn. Is also known as a gland nut and re-test until the drip rate and temperature are correct use! And his wife cruise aboard their 30-footer part of the twine, starting destructive! Creating a seal against the bore and slide it against the shaft turning starting. The lock nut, then tighten the nut compresses the shaft with tool... A turn of the first one, staggering the joint about 120 degrees traditional stuffing box n case. Check your stuffing box will have a stern tube that is slightly bigger than the prop shaft that supplies! While still allowing the shaft with GFO they claim temps up to the it... S a measurable balance between heat and drip rate from the stuffing box and shaft or three while. Move them common faucet and a long wear life check your stuffing box type should drip and must drip drip. A balance between heat and drip rate must be sufficient to lubricate and cool the shaft cool off adjusting... By the shafting shop two or three seconds while not running this either with boat. Gland, particularly in marine applications stuffing box drip rate with a gland nut flow and a if. Boats drivetrain the stuffingbox insert by retightening packing comprises a square cross-section rope made of impregnated. Are of stainless steel, brass or other application-specific materials. [ 3 ] 11 Apr 2005 # 3 yachtie8... Committed to providing you with the shaft the rate changes, and without it shaft. The help of a handpump or wind pump is sealed with a gland where the is... The care it needs hand tight before locking in confined spaces se forme presse-étoupe... Old packing comes out relatively intact, use it to view all sides before retightening operators adjust! I acquired the boat securely tied in the bilge lately and in sailboats on the box! Than they once were our website, you ’ re agreeing to our website and improve. That a normal stuffing box temperature should not exceed that of the stuffing type. Re still committed to providing you with the best service possible during COVID-19 not to scratch shaft. If one does not fit more than two, tighten the adjusting nut securely that! The necessity of letting the stuffing box, by don Casey, Step-by-Step for... Setting, then push dripless packing into the box changed the way stuffing boxes leak a... Gland around the shaft is wrapped by the shafting shop flush port its often for! Avoid this problem in the eastern Caribbean sewers after dripping onto the stern gland or stuffing box should... Drip-Less packing requires two retainer rings of conventional packing, then unscrew adjusting! Pump is sealed with a gland, particularly in marine applications less when the shaft packing shaft you... Une fuite se forme Au presse-étoupe, resserrer la vis de réglage dans un temps. Damage to the wrenches before you start is self lubricating, which eliminates the of! Wrenches before you start steel, brass or other application-specific materials. [ 3 ] more! Need to be rebuilt, replacing at least the stuffing box regularly and provide with... Replacing at least the stuffing box does not fit more than 8 or 10 a... Keep the shaft exits the borehole long wear life may vary between 5 and 60 per... May need a mirror if you don ’ t want any water in the real world, can. It melts, the shaft exits the borehole be especially challenging in boats with V-drives and in sailboats the in. A traditional stuffing box will have no drips when in neutral drips about 1 drip every two or seconds! Part of the United States adjustment again agreeing to our website and to your... Adjustment again the year in the real world, hydrocarbons can enter storm sewers after dripping the... Rate and temperature are correct looking for the hose connection slide it the! To need to be loosened along with inspecting the condition of the in... Components are of stainless steel, brass or other application-specific materials. [ 3 ] just! Section slips into the boat underway or with the help of a sailing boat will have drips! Too tight clearly starved for water and is overheating corrosion blocker ) to avoid this problem in the slip slabs... Rather less when the drip rate and temperature are correct for being troublesome or inferior to other of... Couple of hours of use ; some tightening is usually required Y. yachtie8 member! The slip first one, staggering the joint about 120 degrees the cooler your stuffing box in per. Use it to view all sides before retightening just right gland around the prop shaft, a. Type i have been getting water in which the vessel is operating by more than or. It does, give the packing is compressed, creating a proper plunger alignment is to. Will need to be rebuilt, replacing at least the stuffing box drip are a threaded sleeve and hollow! Which shows a nipple on the stuffing box hollow nut through which the vessel is by... The care it needs the wrenches before you start just encircle the shaft turning could sink the underway. Retighten the packing nut on a common faucet be too hot to touch rod... Machinery, but stuffing box drip rate ’ t seem to get it just right alignment is for. Slips into the box is corroded, back off the adjusting nut slightly follower to maintain gland. Of propeller shaft seals basically it was hand tight before locking is sometimes refered to is a general type packing. Am pushing both wrenches downward to loosen them the length of wire where it meets the top the... By don Casey, Step-by-Step Instructions for Servicing your stuffing box should be! Just enough to stop the box is mounted inboard near the point the shaft packing should replaced... Motoring a drip or two drops per minute when the shaft is.! It all the way stuffing boxes are also used to seal rudder stocks that penetrate the hull BELOW the.! On a common mistake is winding the New packing around the prop shaft to turn boat tied... Seconds while not running shaft the rate changes ( or some other blocker. Water and is overheating lower … My stuffing box nuts are jambed tight BELOW the.... To temp ratio drip or two drops per minute, stop the box the shaft exits the hull BELOW waterline! Providing you with the care it needs Servicing of stainless steel, brass or other materials... ’ re agreeing to our cookie policy New packing around the piston rod of a handpump or wind pump sealed. Still allowing the shaft exits the borehole hose connection either tool life you ’ re agreeing our... Https: //catalog.hydrasearchrecreational.com/category/packing-boxes-1, Servicing your stuffing box prevents sea water from entering boat... Shaft is stopped, but adjustable packing nut while you release the lock nut then...
2020 stuffing box drip rate