what tool do you use to tighten the packing glan on a sailboat shaft
Stuffing Boxes, Shaft Seals, Bearings and Couplings
By Brian Gordon, Concluding updated 6/30/2020
Boats face the challenge of remaining leak-free while spinning one or more propellers outside the hull. Inboard boats use stuffing boxes or shaft seals to prevent h2o from entering the hull. Shaft bearings back up the propeller shaft and help ensure it turns smoothly.
How a Stuffing Box Works
Illustration of traditional stuffing box. (Stuffing box lock nut non shown.)
A stuffing box—also called a stuffing gland, packing gland or packing box—forms a seal between the prop shaft and the hole in the hull through which the shaft passes while allowing the shaft to turn freely. Information technology consists of a threaded sleeve and a hollow nut, through which the prop shaft passes. The nut is filled with rings of wax-impregnated material, called flax packing, and screwed into the sleeve. The packing is compressed around the smooth shaft as the nut is tightened and a little water is allowed to leak into the boat past the packing. The slight water leak serves to cool and lubricate the bearing, while the packing aligning nut allows the flax to be tightened to accommodate for wear. Over time, the seal breaks down and the flax packing must be replaced. Replacement flax is cutting into small rings of textile and inserted into the stuffing box.
Flax Packing
If your gunkhole has a traditional stuffing box (described above) that is leaking excessively in spite of repeated tightening of the nut, you most probable need to supplant the packing. West Marine offers 3 types of packing:
Drip-Less Moldable Packing Kit
Regular flax: Properly installed flax consists of cut lengths of flax, bent into rings, which have their splits staggered around the shaft to minimize leakage. Properly packed flax is compressed and watertight, but decomposes into blackened fluff over time. Note: A properly adjust stuffing box volition permit two or 3 drops of water per minute to enter the gunkhole when the engine is running and the shaft is turning. This small corporeality of water serves to lubricate the shaft. Sealing the shaft completely will cause a buildup of rut and eventually impairment the shaft.
Tallow, Paraffin or Teflon-impregnated flax: Impregnated flax packing is stronger and with Teflon added, creates even less friction against the turning shaft than standard wax impregnated flax.
Constructed packing: An alternative to traditional rope-like flax packing tin can be found in the Drip-Less Moldable Packing Kit offered by West Marine. This is a clay-like substance designed to mold to the inside of the stuffing box to seal without water lubrication. Installation requires that the moldable packing textile be sandwiched between two rings of conventional or impregnated flax. Although referred to as "dripless", some installations may require that a very small-scale amount of water exist allowed to drip into the boat to human action as lubrication and reduce rut buildup.
What size packing does your boat's stuffing box require?
Flax packing comes in many different cross sections, depending on the distance between the shaft and the inside of the packing nut. Here are some guidelines:
| Shaft Size | Suggested Packing Size |
|---|---|
| 3/4" | i/eight" |
| 7/eight" or i" | iii/16" |
| one 1/8" or 1 1/four" | one/4" |
| i 3/viii" or 1 3/4" | v/sixteen" |
| 2" or 2 1/8" | 3/8" |
How to Install Flax Packing
Tools: To supercede flax packing, you need two wrenches: one to release the lock nut that holds the packing aligning nut in place and one to unscrew the packing nut itself. Use a corkscrew shaped packing extractor to dig out the onetime packing being certain to salve some and then it can be measured for replacement.
How much packing material is needed?
Traditional flax packing
In full general, multiplying the shaft diameter by 14 will yield the approximate number of inches of new flax packing necessary for four layers of new packing.
How to pack: Curve the new flax into rings around the shaft and printing them into the stuffing box, staggering the joints between layers. Retighten the packing nut to shrink the flax effectually the shaft and slow the water drip rate. Proper compression allows about two drops per minute. Run the engine in gear and then readjust the nut to achieve this rate.
Shaft Seals
The large advantage of shaft seals is that they eliminate the need for flax packing and the knuckle-busting experience (for some) of periodic tighening of a stuffing box nut. Shaft seals replace traditional stuffing boxes by using two polished surfaces, 1 stationary and 1 rotating, which grade a seal around the prop shaft and don't leak a drop. These seals take the reward of existence impervious to temperature, vibration and corrosion. They practice not need any maintenance.
Packless Sealing System. Annotation the Flexible shaft coupling between the transmission output flange and the shaft coupling.
The Packless Sealing Arrangement
Westward Marine offers the Packless Sealing Organization (P.South.S.) shaft seal past P.Y.I. The system uses a high-density carbon/graphite flange that is attached to the gunkhole's stern tube (too chosen a shaft log) by a nitrile bellows that uses water force per unit area to create a 100% watertight seal. The seal is non affected by temperatures, saltwater, corrosion, chemical or UV exposure. These seals are offered in a variety of sizes and the controlling dimensions are the shaft diameter and the bore of the stern tube. Sizes are bachelor for all engines, regardless of rpm.
Important tip for dripless shaft seals!
Drip-proof shaft seals such as the P.Southward.Due south. seals described in a higher place must be "burped" earlier the boat is operated after a haul-out. This is done by pulling the prophylactic bellows slightly to let h2o push the air inside the seal out. If this is not done, the shaft seal will get hot chop-chop (without water contact) and destroy itself.
R&D Marine's Flexible Shaft Coupling
Flexible Couplings by R&D Marine
If you are planning to install a P.S.S. sealing organization, consider also installing a flexible coupling by R & D Marine. This flexible coupling installs between the transmission output flange and the shaft flange to absorb shock loads resulting from gear changes or from the propeller striking a submerged object. It's fabricated with a polyester elastomer and the metal compression strap that keeps the coupling intact if the disc is destroyed, ensuring that the bulldoze system still functions. R & D Marine flexible couplings come with the required installation hardware and are bachelor for engines from 5 to 1,500hp.
Do you demand a new shaft bearing?
If you experience excessive vibration or hear the sound of a dinner bell when you put your boat in gear, yous might need a new shaft begetting. As mentioned, traditional shaft bearings are rubber-lined brass sleeves that mount inside the support strut or stern tube that supports the propeller shaft. In addition to traditional rubber/contumely bearings, Trellex-Morse also offers shaft bearings with a non-metallic sleeve. Shaft bearings are designed to slide tightly into the stern tube housing or strut and the prop shaft passes through the center of the bearing. The nitrile safe lining of the bearing prevents vibration, permits the shaft to turn freely and allows water to lubricate and cleanse the shaft as it turns.
Trellex-Morse Shaft Begetting
Shaft bearings come in many sizes because of the tight tolerances necessary to achieve a proper fit. They are specified past shaft diameter, outside diameter and length. West Marine stocks a large option from Trellex-Morse. The bearings apply fish names that bespeak inner tube diameters: Albacore, Barracuda, Cod, etc. The first letter of the alphabet of the name denotes the I.D. of the bearing (A=three/4", B=1", C=1 1/4", etc.) Other important dimensions are the outer tube diameter and length.
Shaft Begetting Installation
Shaft bearings are really much easier to install so they are to remove. When attempting begetting maintenance, the prop shaft must first exist removed to prevent whatsoever impairment to it. The begetting tin be installed by gently tapping it into the strut with a safe mallet. Information technology is usually held in identify by a setscrew or flange. Once the begetting fails (as information technology will eventually) information technology is nearly impossible to excerpt them from the strut or stern tube unless the boat has been hauled. If light tapping with a dowel or pivot dial doesn't piece of work, try using a hacksaw or Sawzall to remove information technology, taking care not to saw into the stern tube or strut. Although the old bearing is destroyed this manner, it doesn't really matter because information technology'south useless in one case it'southward worn out.
Available Shaft Bearings
Below are links to four types of Trellex-Morse shaft bearings. As mentioned, West Marine carries many, but not all of the bearings that Trellex-Morse makes. If your boat requires a bearing that West Marine does not stock, delight speak with a shop acquaintance or call ane-800-262-8464 to place a special guild.
Standard Non-Metal Series
Standard Brass Sleeve Series
Brass Flanged Series
Metric Series
Source: https://www.westmarine.com/WestAdvisor/Stuffing-Boxes-Shaft-Seals-and-Shaft-Bearings
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