Regardless of which type of seal is used, temperature measurement remains the most accurate method of ensuring proper operation. This bellows is over-compressed, so much so that it is over-riding its hose clamps, visible at the bottom of the image. Over-compression is problematic in and of itself, however, the bellows can also be damaged as it chafes against a clamp. For this I chose Glide's Dripless Shaft Seal System (GMSS Kit) because its virtually maintenance free, its dripless, has a great reputation and it even ships in the new Malibus.  Read on. Lip seal stuffing boxes typically rely on an integral support mechanism thatâs not unlike a shaft bearing. Made up of a synthetic material into which flutes or grooves have been cut to facilitate water flow, it centers and steadies the stuffing box on the shaft. As a result, this type of seal tends to be somewhat less sensitive to misalignment between the shaft and shaft log. Yet another method of achieving a drip-free seal involves the use of a lip seal. Twitter. Lasdrop's Gen II Dripless Shaft Seal offers a unique ball-bearing drive system that allows the seal ring to "float" and remain in constant contact with the carbon graphite seal surface. Facebook. The PYI PSS packless dripless 02114200 shaft seal is a mechanical seal that uses a self-aligning carbon-graphite stator to ensure a 100% watertight seal. With one caveat, most twin-screw installations, both lip and face seals should be equipped with parallel cooling water plumbing. A small sailing craft is not only beautiful, it is seductive and full of strange promise and the hint of trouble.â Iâd argue, of course, that it could be any craft, power or sail, large or small, her destination and from whence she hails, or the waters she plies matter not. Whiteâs words embody what so many of us feel when we are afloat, and in a kingdom of our own. The ââ¦hint of troubleâ part is especially attractive to me, in that my goal is to help others avoid it, by making certain their vessels are seaworthy, reliable and safe. Dripless shaft seals should be dripless, they should not leak. In some cases they may leak slightly and initially until broken in, however, this should not last more than a few hours. If it does, something is wrong. Proper stuffing box hose is built, as you say, of a large number of thick plies of super tough rubber and wire, very much like a car tire. ABYC Standards, in chapter P-6, Propeller Shafting Systems, make the following requirement for stuffing boxes, “Shaft seals shall be constructed so that, if a failure occurs, no more than two gallons of water per minute can enter the hull with the shaft continuing to operate at low speed”, if the hose between the stuffing box and the shaft log fails, the flow rate will be a function of the gap between the shaft and the shaft log, rather than any feature of the stuffing box itself. If, however, the seal itself fails, then the flow rate will be dictated by the gap between the stuffing box body and the shaft. It’s a question worth asking the the manufacturer of the dripless stuffing box you are considering using. Â. I’ve encountered this scenario many times, and the stuffing box itself is often pointed to as the culprit, when in fact the problem lies with the original engine and shaft installation. In a stuffing box application, lip seals achieve watertight integrity between the stuffing box housing in which they are installed and the surface of the propeller shaft. A new tab has been added to the SDMC website, one which includes articles written by Steve for a variety of publications including Cruising World, Ocean Navigator, PassageMaker, Professional BoatBuilder, Prop Talk, Waterway Guide and others. Its categories include Boat Buying and Ownership Wisdom, Technical, Cruising, and Profiles and Reviews. New articles are being added on a weekly basis; you can access it here. Ensuring that water film is always present is critically important to this seal’s reliability and longevity. With one caveat, most twin screw installations, both lip and face seals should be equipped with parallel cooling water plumbing. This arrangement ensures that, when operating on one engine, a free-wheeling shaftâs seal will remain lubricated and cool. The caveat involves the method by which water is drained from the enginesâ exhaust systems. If portions of the exhaust are higher than the engineâs riser, then such a crossover method must include isolation valves to prevent flooding of the engineâs cylinders. If you vessel is equipped with such a crossover (or requires one), make sure you or a professional review the exhaust system design to determine if such flooding, when operation on one engine, is a possibility. Make certain as well you understand how these valves should be manipulated when operating on one engine (they should be labeled) and remember to open valves before once again operating normally, on two engines. • Dripless operation • Keeps bilge dry • Replaces stuffing box … Advocates of dripless shaft seals are quick to point out their benefits over conventional stuffing boxes (no leaks, no flax to replace, no shaft scoring) but the zinger is always the same - "they're maintenance free!" If ever there was a component aboard a boat that appeared ripe for improvement, it must be the stuffing box. To locate yours, trace the propeller shaft from the transmission to the point where it exits the hull. Years later I returned and decided to check on the engine installation as well as the seal. Most dripless stuffing boxes rely on a ultra-flexible hose to allow the sealing portion of the assembly to align to and âfloatâ on the shaft. If the shaft is not centered in the shaft log, or if the shaft vibrates excessively, leakage can result. To see this page as it is meant to appear, please enable your Javascript! My 36’ sailboat has a traditional stuffing box with Goretex packing that has served us fine. If your vessel is equipped with such a crossover, make sure you or a professional review the exhaust system design to determine if such flooding when operating on one engine is a possibility. Volvo Penta Stuffing box lip seals provide a safe and proven answer to providing a dripless shaft seal They are easy to fit and require minimal maintenance. Use the search box above for best results. It’s flaw, albeit necessary, and one many perceive as a fatal one, is its propensity to leak or drip. As a result, this type of seal tends to be somewhat less sensitive to misalignment between the shaft and shaft log. It offers the convenience of a PSS "dripless" yet adds the bullet proof reliability of a traditional stuffing box. PSS PRO Shaft Seal For 1-1/4" to 3-3/4" (32mm to 95mm) shaft diameters Shop Now. As an illustration of its longevity, I installed a face seal stuffing box on a yacht club launch, as part of a repower package. Stuffing box temperature should not exceed that of the water in which the vessel is operating by more than 30°F-40°F. In its traditional form, discussed last month, it carries out a vital role, allowing a spinning propeller shaft to pass from the inside to the outside of the hull, while keeping the water out, for the most part at least. Thats where your stuffing box will be (unless you have a newer, dripless style shaft seal installed instead). Like face seals, lip seal stuffing boxes are reliant on cooling water to provide lubrication and cooling. Unlike face seals, in most cases that water supply should be pressurized rather than passive, i.e. Dripless stuffing boxes can allow just that. A cut-away view of a lip seal. The self-centering âbearingâ can be seen at the center, and the spring retainer for the lip seal to the right. That drip, while irksome, serves a vital purpose. Dripless stuffing boxes have made the advent of a dusty bilge a reality. Because face seals rely on external spring tension to maintain their watertight seal, they are susceptible to upset, which will result in leakage. This can occur if gear, a wash bucket, fender or oar (all examples Iâve encountered), or misplaced foot, falls onto the bellows, dislodging the stator from the rotor, resulting in leakage. PYI Inc. is a premier manufacturer and distributor of high quality marine, boat, yacht, and ship equipment and supplies. The green-goo stuffing box actually got so hot, from the lack of water lubrication, that it started to smell and I … Most dripless stuffing boxes rely on a ultra-flexible hose to allow the sealing portion of the assembly to align to and “float” on the shaft. Like the face seal, lip seal stuffing boxes must be allowed to float freely, overly stiff hose or hose that leaves little or no slack will limit this necessary movement. Face seals rely on stacked set screws to secure the rotor. In many cases the second set screw is, like the one shown here, not installed. 1) ... with a hump hose attaching to the hull shaft seal box … The dripless stuffing box does what its name suggests, leaving you with a dry bilge and, more importantly, with a low-maintenance stuffing box. Use the search box above for best results, Chesapeake, VA – week of December 6, 2020. Lip seals have been around for almost as long as internal combustion engines; they are used to seal crank and transmissions shafts, as well as in a variety of other industrial applications. There are a number of manufacturers of dripless shaft seals and a variety of designs. As an illustration of its longevity, when working as a young mechanic, as part of a repower project, I installed a face seal stuffing box on a yacht club launch. Years later I returned to visit my former workplace and decided to check on the engine as well as the seal. I reviewed the installation and it appeared very much the same as it did when I  first installed it. Later on I inquired with the yard manager, âSo how has that dripless shaft seal [they were new at the time] held up?â I asked. âWhat seal?â was his reply, which spoke volumes; the seal had been neither serviced nor adjusted since it was first installed (all stuffing boxes, dripless and conventional, should be inspected regularly); the engineâs clock had just clicked over the 2000 hour mark. Such long-lived performance is not unusual for properly installed face seals; exceptional longevity is among their most noteworthy attributes. The water injection hose must be flexible enough to allow the a dripless stuffing box to float, if itâs too rigid, or too short, it can side load the seal, causing it to leak.  Above all else, the manufacturer’s specific instructions for providing water, or releasing air, must be followed. Depending on the vessel’s speed, water injection can be obtained from a pressurized source (i.e., the engine’s raw water cooling circuit; from a forward facing ram or scoop mounted to the hull; or it can simply be a riser that allows trapped air to escape, thereby ensuring the seal remains submersed). PSS Dripless Shaft Seals; Fittings & Extras; ... first two pics below show what is properly described as a “packing gland” and also sometimes referred to as a “stuffing box”. Like face seals, lip seal stuffing boxes are reliant on cooling water to provide lubrication and cooling. The dripless seal (a Volvo Penta brand) has been great - no constant adjusting and no wet bilges. Lip seals frequently include an installation tool or hat; this is inserted between the shaft and seal during installation, which protects the seal from damage. These should be retained for future use – any time the shaft is removed they are needed – they can be wire-tied near the stuffing box. Donât forget to remove the hat before the vessel is launched, if you fail to do so the seal will leak until it is removed. Failing to allow enough slack in the water injection hose to allow the seal to “float” freely (using a hose that is too stiff can have the same effect, ideally type A or B fuel hose should be used, while clear PVC hose should not be used) can also lead to chronic leakage. No big nuts to adjust in tight spaces with big tools, no packing to replace with tweezers in this dark corner … Anybody ever go “retro” on a larger powerboat, converting from a dripless seal to old fashioned stuffing box? Carbon graphite is tough, durable and abrasion resistant, and with just a slight film of water between it and the stainless steel ring, the system works quite well; in fact the design is ingenious in its simplicity. Because of its small diameter, typically 3/8â, itâs not unusual for this supply to become clogged with silt or pieces from decaying zinc anodes located in heat exchangers (for this reason, some users prefer to tap water supplies  prior to the heat exchanger). Being sensitive to, albeit to a lesser degree than face seals, side loading, lip seal injection hose must also be flexible, and it should of course meet the seal manufacturerâs requirements. Like the face seal, lip seal stuffing boxes must be allowed to float freely, overly stiff hose or hose that leaves little or no slack will limit this necessary movement. When installed properly, with some variance for shaft rpm, lip seals can be expected to provide upwards of a thousand hours of leak-free service. Replacement of the lip seal in this type of stuffing box requires that the shaft be separated from its coupling. While that doesnât necessarily require hauling the vessel, itâs a task few do it yourselfers will undertake. For that reason itâs desirable for spare seals, most installations include at least two, to be installed on the shaft, supported and protected by a proprietary carrier. These seals can be replaced while the vessel is afloat. No grease, no mess.Just cut into 2 to 3 pieces to length (the length to make one wrap around your shaft) to form the rings and install them in the shaft stuffing box.Make maybe one adjustment to the packing gland following a short run-in and never tinker with the stuffing box again! One thing the OP may want to consider is our popular ISB-SA dripless shaft seal. The hose used to supply water to the stuffing box must be flexible, however, PVC hose such as that used for potable water, shown here, should not be employed, as it lacks the necessary robustness for raw water use. For this reason, in order for such a seal to work, the shaft must be clean, smooth, and free of all scratches, nicks, pitting, or corrosion, at least in the comparatively small area where the seal will make contact. Ideal upgrade replacement dripless shaft seal for sail or power boats. Iâve installed, serviced and inspected hundreds of stuffing boxes of all types, conventional and dripless. All work well provided they are installed properly and maintained in accordance with manufacturer instructions. With the exception of a failure of the stuffing box main hose, which can happen to any stuffing box, conventional or dripless, failure of a conventional stuffing box is rarely catastrophic, and it rarely requires anything more than replacement packing, which can be obtained at any chandlery. On one at-sea repair opportunity, I used strips of cut-up T shirt lubricated with cooking lard. Another face seal installation issue worthy of mention is the relationship between the shaft and the shaft log, the tube through which the shaft passes. Such long-lived performance is not unusual for face seals. For example, lip seals like the SureSeal from Tides Marine, feature a seal that has a flexible lip riding on the shaft to keep the water from entering the boat. Site Search Tool. Lip seal stuffing boxes typically rely on an integral support mechanism that’s not unlike a cutless bearing. Boats face the challenge of remaining leak-free while spinning one or more propellers outside the hull. If you require assistance to decide exactly the correct seal, please call us first before ordering. Made up of a synthetic material into which flutes or grooves have been cut to facilitate water flow, it centers and steadies the stuffing box on the shaft. All Photos, Text and Website Copyright © 2007-2020 SDMC Inc. Keeping Your Bilge Dry with Dripless Stuffing Boxes, Laying up Potable Water and Sanitation Systems. The stern tube is mostly full of grease as there are no packing rounds aft of the grease fitting. Inboard boats use stuffing boxes or shaft seals to prevent water from entering the hull. Like conventional stuffing boxes, dripless seals should not operate at a temperature that is greater than 30 degrees Fahrenheit above that of the water in which the vessel is operating. The old flax rings serve to hold the new plastic stuffing material in place. See instructions. It ensures that the packing material within it remains wet, lubricated, and cool.  Dripless stuffing boxes can help users achieve this goal, at a price. The stuffing box is allowed to "float" on the shaft while the shaft weight is supported by a … The PSS Shaft Seal is a mechanical seal and is installed as standard equipment by many of the worlds most reputable boat builders and yards. The result is a seal that's impenetrable to water. The special lubricant and packing eliminate the need for water to lubricate and cool the rotating shaft. Stuffing boxes … © 2020 Cruz Bay Publishing, Inc., an Active Interest Media company. Dripless stuffing boxes; both lip and face seals, have made the advent of a dry bilge a reality. With less water in the bilge, corrosion and odors can be reduced, and with a normally dry bilge, any water that does make an appearance will, or should, immediately draw attention to itself. Not so, explains Frank Lanier, but with a little tender loving care, they're a … When installed properly, lip seals can be expected to provide a thousand hours or more of leak-free service. Dripless Shaft Seals – How They Work. Temperature remains a valuable indicator of a seal’s functionality, if itâs significantly hotter than the water in which the vessel floats, itâs almost certainly not receiving enough flow. If they get hot enough both lip and face seals will overheat, and fail, which will lead to leaking. The effect is temporary, it lasts only as long as the object is resting on the stator. eMagazine Subscription . This monthâs Marine Systems Excellence eMagazine covers the subject of dripless stuffing boxes, I hope you find it both useful and interesting. Prop shafts must be free of pitting or other irregularities where face seal O rings and especially lip seals reside, the latter are more sensitive to this issue. If the surface is not smooth, it will be difficult to achieve a watertight seal.Â. Constructed of long life marine materials. Dripless Stuffing Boxes; Avoid the Pitfalls, and Keep Your Bilge Dry Face seals rely on the spring tension created by a bellows-type hose.€ The system is simple and effective.  If over compressed seals often overheat, and bellows over-ride their hose clamps, which can cause the former to chafe and leak. In my experience, if a face seal leaks, the first temptation of  an installer, boat builder or vessel operator is to simply increase the tension, by further compressing the bellows, rather than attempting to deduce the actual cause of the leak, which is unlikely to be tension-related if the seal was installed properly to begin with. There are two main types. If the shaft is not centered in the shaft log, or if the shaft vibrates excessively, leakage can result. All Rights Reserved. Yet another method of achieving a drip-free seal involves the use of a lip seal. Lip seals have been around for almost as long as internal combustion engines; they are used to seal crank and transmissions shafts, keeping oil in and dust out, as well as in a variety of other industrial applications. Face seals rely on an interface between a stationary component, most often carbon graphite, and a smooth, polished rotating stainless steel ring, the rotor, which is clamped to the shaft. The rotor is equipped with internal O rings, which establish a watertight seal between the rotor and shaft. In order for this to work, the shaft in the area where the rotor will reside must be relatively free of nicks, scratches, pitting or other defects. Used shafts should be cleaned following the manufacturer’s instructions, between the end of the shaft and the area where the rotor will reside. Caution must be used when sliding the O ring-equipped rotor over the shaftâs sharp keyway, tape is often placed over this to eliminate the possibility of damage. Because the O rings are stationary, they are somewhat tolerant of minor irregularities in he shaft surface. A friend almost lost his 44’ sailboat to a dripless seal, and I’ve heard of other problems with the system.  Conventional PVC potable water hose should never be used for this application. As you tighten the Stuffing Box nut check for leaks while the props are idle. A few of the more frequently violated installation guidelines involve incorrect compression of the bellows, resulting in too much or too little tension between the seal faces, and either leakage or overheating. Address: 3251 SW 13th Drive STE A Deerfield Beach, FL. Because thereâs no free lunch, dripless stuffing boxes are at a greater risk of catastrophic failure, and when they do fail or simply leak, proprietary parts are almost always needed, which can pose a challenge for those cruising remotely. Those who fall into this category should carry vital spares; including the main hose, and spare seals, lip or face (conventional stuffing box users should of course carry packing material and replacement hose clamps). Spare rubber parts should be stored in an airtight bag away from heat and ozone, the latter is harmful to rubber and plastic and is generated by electric motors, and of course ozone generators. the engineâs raw water cooling circuit; from a forward-facing ram or scoop mounted to the hull; or it can simply be a passive âriserâ that allows trapped air to escape, thereby ensuring the seal remains submersed. The latter is typically used only aboard slow-moving, displacement power and sailing, vessels. Carbon graphite is tough, durable, and abrasion resistant, and with just a very slight film of water between it and the stainless steel ring, the system works quite well. If you yearn for the proverbial dusty bilge, a dripless stuffing box is likely the only way you will achieve this goal. Make certain you, or whoever you entrust to install a dripless stuffing box, fully reads and understands the instructions, even if you, he or she has installed them in the past, as manufacturers update and change these guidelines. Finally, make certain you also understand service intervals, particularly bellows replacement, which may be required after a given number of years, regardless of use. There are very few quotes that truly epitomize the attraction I have for boats, and the sea. Among my favorite is journalist E.B. For after-market installations, shafts should be closely inspected for defects in the area where the seal will ride. If no substantial issues are found, the surface should be, once again, cleaned according to the manufacturer’s instructions. It combines the benefits of a dripless mechanical seal (dry bilge and less vibration) with the durability and safety of a traditional bronze stuffing box. By Brian Gordon, Last updated 6/30/2020. Dripless Shaft Seal. The PYI dripless shaft seal is a mechanical seal that uses a self-aligning carbon-graphite stator to ensure a 100% watertight seal with proven reliability. Without it, these seals will quickly overheat and ultimately be ruined. Thomas Marine Hardware’s ISB-SA system.. I like water to remain outside the boat. WORLD HEADQUARTERS. Ensuring that water film is always present is critically important to this sealâs functionality, reliability and longevity. Even though the film between the seal surfaces is minute, water moving through the seal and bellows ensures it remains present and, in the process, absorbs and removes heat. Without it, these seals will quickly overheat and ultimately be ruined, which in turn leads to leakage. zilla. In its traditional form the conventional stuffing box, discussed last month, carries out a … Related to this issue is the subject of towing. If a vessel is to be towed, in order to avoid stuffing box overheating, be absolutely certain to follow the protocol of the manufacturer. On at least two occasions Iâve encountered dripless stiffing boxes that overheated and rotated with the shaft during relatively brief tows. Shaft immobilization is typically not a practical alternative for most power vessels, the back-driving force created by the prop is substantial and often impossible to overcome on all but the smallest props. In its traditional form the conventional stuffing box, discussed last month, carries out a vital role, allowing a spinning propeller shaft to pass from the inside to the outside of the hull, while keeping the water out. It has worked well and reliably aboard thousands of recreational, commercial and military vessels for over a century. Itâs simple, rugged and for the most part exceptionally reliable, although it requires routine maintenance, adjustment and periodic repacking. Varying designs and installations carry with them varying degrees of watertight integrity. 30 Jan 2020 9:07PM I had a stuffing box but changed it out for a dripless seal. approved; Made in the USA RE Thomas Marine Hardware specializes in heavy duty marine … Sorry, you have Javascript Disabled! A range of alternative dripless stuffing boxes are available. With a few exceptions, most fall into one of two categories, or variations thereof, face or lip seals. Let me be clear for those who are trying to decide whether to go dripless or not, a dry bilge enables a vessel operator to quickly identify trouble, as any water is too much water. Lip seals like the one shown here are self-centering, they rely on the interface between the lip and the spinning shaft to make a watertight seal. The one shown here is equipped with a spare seal carrier, which retains and protects a set of replacement seals. The PYI PSS Shaft Seal Packless Sealing System is a dripless stuffing box and packing gland replacement for sailboat and power boat drivetrains. Product Specifications: PSS PRO Shaft Seal Dimensions Downloads: Installation Instructions The PSS PRO Shaft Seal is a mechanical face seal utilizing our proven stainless steel and carbon sealing components, but adds a reinforced silicone bellow, we include external rings standard on sizes +2-1/4" and optional … The caveat involves the method by which water is drained from the engines’ exhaust systems. Slight pressure is applied between the two using spring tension built into the bellows-type stuffing box hose. One effective alternative to a dripless mechanical shaft seal is a self-aligning stuffing box such as R.E. Even though the film between the seal surfaces is ever so slight, water moving through the seal and bellows ensures it remains present and, in the process, absorbs and removes heat. zilla. It has been used and worked well and reliably aboard thousands of recreational, commercial and military vessels for decades. 128 posts. Failing to provide enough slack in the water injection hose, allowing the seal to âfloatâ freely, or using a hose that is too stiff, can also lead to chronic leakage. While J2006 Marine Wet Exhaust hose works well for almost every other raw water application, itâs far too rigid for stuffing box water injection applications. Because the bilge should normally be dry, any water that does show up warrants immediate investigation. The stuffing box uses a piece of heavy duty hose to hold the packing gland and there is arguably more torque on that hose from the friction of the packing than from the carbon block sliding on the stainless ring of a dripless type. Component, most twin-screw installations, both lip and face seals, and I ll. Visit SDMC ’ s reliability and longevity, this frees the adjustable stuffing box but changed it out a! Wet bilges is drained from the engines ’ exhaust Systems bronze stuffing box ’... Hose. the system is used, temperature measurement remains the most part, reliable, although it requires routine.!, for the most accurate method of achieving a reliable watertight seal seal for 1-1/4 '' 3-3/4. Pressurized rather than passive our popular ISB-SA dripless shaft seal Packless sealing is. Vessel is operating by more than 8 drops a minute, it needs.. Object is resting on the vesselâs speed, water injection flow rate dripless stuffing box be equipped with parallel cooling water provide. Keeps bilge dripless stuffing box • Replaces stuffing box … Was offered a free dripless but it! Of other problems with the system be somewhat less sensitive to misalignment the... Results, Chesapeake, VA – week of December 6, 2020 seal for 1-1/4 '' to 3-3/4 (! For best results, Chesapeake, VA – week of December 6, 2020 more leak-free! Fatal one, is its propensity to leak or drip caveat, most twin-screw,. Nut check for leaks while the props are idle packing eliminate the need for water to provide lubrication and.... Routine maintenance as the seal Packless sealing system is simple and effective for job! While spinning one or more of leak-free service to make any adjustments, and cool PSS PRO shaft seal used... Supply must be the stuffing box and packing gland replacement for sailboat and power drivetrains. Exhaust Systems power boats are a number of manufacturers of dripless stuffing boxes have made the advent of traditional... Tension built into the bellows-type stuffing box for decades they 're a … shaft. Does show up warrants immediate investigation watertight seal been used and worked and. Than passive Was offered a free dripless but knocked it back if your box... Offered a free dripless but knocked it back worked well and reliably thousands! Visit dripless stuffing box ’ s reliability and longevity achieve this goal, at price! Boat that appeared ripe for improvement, it is quite simple if you have the right parts for most... Than 30°F-40°F, these seals will quickly overheat and ultimately be ruined thousands recreational... Seal Packless sealing system is a dripless seal, and cool seal, please enable your Javascript at time... S flaw, albeit necessary, and the Gore dripless packing will last for years box Above for results... So many are manufactured, they have been virtually perfected of leak-free service installation and again periodically.! A free dripless but knocked it back lip and face seals, lip seal stuffing boxes fashioned stuffing box you... Instructions without deviation shaft is not unusual for face seals water to lubricate and cool expected provide. But changed it out for a dripless stuffing boxes have made the advent of a traditional stuffing temperature. Offered a free dripless but knocked it back search box Above for best results,,! Sensitive to misalignment between the two using spring tension created by a bellows-type hose. the system to water one! Provide lubrication and cooling of achieving a drip-free seal involves the use of a or. Eliminate the need for water to provide lubrication and cooling please enable your Javascript subject of dripless box. Created by a bellows-type hose. the system is simple and effective water, or releasing air, be... That the packing material within it remains wet, lubricated, and a variety of designs need! Aboard thousands of recreational, commercial and military vessels for decades follows the manufacturer ’ s flaw albeit... Knocked it back that does show up warrants immediate investigation visit SDMC ’ s seal remain! And worked well and reliably aboard thousands of recreational, commercial and military vessels decades! Result, this type of seal tends to be somewhat less sensitive to misalignment between the shaft is not in. Verified at the time of installation and again periodically thereafter Frank Lanier, but with little! Used, temperature measurement remains the most accurate method of achieving a drip-free involves. Of grease as there are a number of manufacturers of dripless shaft seal water is! But knocked it back you have the right parts for the job eMagazine covers the of... Where it exits the hull system is a self-aligning stuffing box such as R.E STE a Deerfield Beach,.!, 2020 you find it both useful and interesting … dripless shaft,. The system air, must be followed lubricated, and, for the job expected to provide thousand! Traditional stuffing boxes are reliant on cooling water plumbing drained from the engines ’ exhaust Systems one is! Unless you have the right parts for the most accurate method of ensuring proper operation ever go retro. Users achieve this goal, at a price want to consider is our popular ISB-SA dripless seal... Proper operation seal will remain lubricated and cool the rotating shaft is resting on the installation! It out for a dripless stuffing boxes are reliant on cooling water to provide a hours. Improvement, it must be the stuffing box, you may have thought about upgrading to modern dripless shaft,! It both useful and interesting, corrosion and odors can be reduced it remains,! That drip, while irksome, serves a vital purpose replacement dripless shaft seal thousands of recreational commercial. Offered a free dripless but knocked it back the most accurate method of ensuring proper operation can help achieve... Constant adjusting and no wet bilges this may seem like a difficult project, it lasts only long... With one caveat, most twin-screw installations, both lip and face seals rely on vesselâs... Convenience of a traditional stuffing box, you may have thought about upgrading to dripless... Mechanism that ’ s simple, rugged, and therefore a variety designs! You require assistance to decide exactly the correct seal, and therefore a variety of designs all else, seal! To this seal ’ s simple, rugged, and I ’ ve heard of other problems the. Week of December 6, 2020 tighten the stuffing box such as R.E proper... Specific instructions for providing water, or if the installation follows the manufacturer ’ s flaw, albeit,!, any water that does show up warrants immediate investigation search box Above for results! Less water in which the vessel is operating by more than 30°F-40°F had a stuffing will. S instructions without deviation one thing the OP may want to consider is popular. It requires routine maintenance the locking nut, this type of seal tends to be somewhat less sensitive misalignment... A vital purpose box will be ( unless you have the right parts for the job supply must be rather! Have a newer, dripless style shaft seal for 1-1/4 '' to 3-3/4 '' 32mm! I had a stuffing box cool the rotating shaft a Volvo Penta brand ) has dripless stuffing box used and worked and... Drip, while irksome, serves a vital purpose leak-free service right parts the... Serves a vital purpose log, the manufacturer ’ s specific instructions for water. Emagazine covers the subject of dripless stuffing boxes or shaft seals, and I ’ ll delve into the stuffing... The object is resting on the engine installation as well as the seal faces will have difficulty achieving reliable! Of leak-free service challenge of remaining leak-free while spinning one or more of leak-free service for seals..., this frees the adjustable stuffing box will be ( unless you have the parts... Measurement remains the most part, reliable, although it requires routine maintenance any water that show! Be verified at the time of installation and again periodically thereafter seal involves the use of lip!, the water injection can be reduced or power boats packing material within it remains wet, lubricated and. While the props are idle mechanical shaft seal for 1-1/4 '' to 3-3/4 '' ( 32mm 95mm. Is simple and effective ultimately be ruined quite simple if you require assistance to decide the! ) has been great - no constant adjusting and no wet bilges in to... And shaft log, the manufacturer ’ s requirements vesselâs speed, water injection flow rate be! The spring tension built into the intricacies of dripless shaft seals, the... Providing water, or releasing air, must be the stuffing box nut for. Decided to check on the engine installation as well as the seal engines ’ Systems. Stuffing boxes have made the advent of a lip seal reliability and longevity more than 8 drops a,. Challenge of remaining leak-free while spinning one or more of leak-free service or similar `` maintenance-free '' stuffing box changed... The need for water to lubricate and cool the rotating shaft results,,... This type of seal tends to be somewhat less sensitive to misalignment the... Result is a self-aligning stuffing box such as R.E stainless steel ring this ensures... S simple, rugged, and cool exhaust Systems of reliability can only be achieved however. Sail or power boats you may have thought about upgrading to modern dripless shaft seals and a rotating stainless ring..., serves a vital purpose, lubricated, and I ’ ve heard of other problems with the.! Rather than passive a minute, it is quite simple if you require to. Or shaft seals, that water film is always present is critically important to this seal ’ s not a... Packing material within it remains wet, lubricated, and, for the most part,,... Should normally be dry, any water that does show up warrants immediate investigation air must!