How To Repair Floating Dock Leaks

Dealing With Leaks

At that place is no bespeak in doing anything on a gunkhole unless you take the time to do it right. -- Anonymous

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It's a fact of life that boats leak. Information technology's also true that as boats age, leaks tend to increase for the simple reason that sailing yachts are under a lot of stress. And in these times when builders emphasize speed and lightweight, the issues with leaks worsen since laminates are not as thick nor are hulls as rigid every bit they used to be.

Leaks are not merely inconvenient and aggravating, but also cause damage to personal gear and the gunkhole itself. The source of leaks are unremarkably hard to find and even harder to stop. The typical case is where the water enters at point A, but shows up at point B, which is six feet away from point A. The owner spends weeks attempting to search out the source so that he tin can repair it. These are usually instances where inner liners work to distribute the leaks to points far from the source of entry, and are often the subject of many wry jokes.

As an aside here, I want to mention something that I see very frequently that is just a waste of time and makes a mess of things. That is the way some people endeavour to take the easy manner out past just smearing some caulking on the outside of an open up seam. On boats, to make an effective seal, the caulk has to go between the two parts that are mated, and this is called bedding. Achieving this is not easy, but it is the merely way to effectively stop leaks. Moreover, with the way many boats are hurriedly congenital today, parts are often never bedded properly from the get-go. If that is the case, and then you take to go back and do what the builder did not practise correctly.

Of course, the granddaddy of all leaks is the leaky hull-to-deck join, which is usually the most difficult of all to repair. I've seen numerous boats where the deck joint leaks so bad that either the boat is uninhabitable, or the boat has become severely damaged as a effect of rotting internal plywood structures, moisture bedding and the like. Vee berths in both power and sail boats are often a victim of this problem, where you end upward with both rotting mattresses and structures. Ouch! This gets expensive.

In many instances, the manner in which the deck is joined is such that effecting an economic repair is most impossible, or that the leakage is so pervasive -- significant that the deck join is leaking everywhere -- that the deck needs to be removed and reinstalled anew, which as well means that it's probable to be more economical to get rid of the boat and buy another i, than it is to attempt to repair it.

For these reasons, when considering the purchase of whatsoever used boat, it is of paramount importance to cheque the gunkhole over for leaking deck joints; this is not a problem that anyone should buy into. Leaking deck joins are about intractable when associated with working hull structures. Not all boats are as rigid equally they should exist, and if the rigging is causing compression loading, both fore and aft, too equally transversely, and so attempting to repair leaking deck joins may be an practise in futility.

Checking a boat for leaks is fairly easy. Just beginning opening things upwards and looking. The usual indicators are, aside from the evidently obvious, are numerous rust stains where canned goods were stored, rusty tools and mattresses wet on the undersides. If not wet, look for stains on the difficult booth surface. Check out any place on the interior of the hull sides where you may be able to see water trails or heavy amounts of mildew. Water stains on headliners, discolored cabin soles, damaged paneling, water puddles or water lines under berths or other places that trap water. The number of indicators is near endless.

It's a fault to think that repairing leaks is a relatively modest problem that can be done at depression price. Aye, repairing a leak is ordinarily a uncomplicated matter, but the fact is that in that location is often no access to the area that needs repair, so that to make the repair requires violent out a part of the interior. Such is often the example with chain plates and other deck hardware.

Concatenation Plates

As any experienced sailor knows, the virtually common source of leakage is at the shroud chainplates where they pass through the deck. Considering of the frequent loading/unloading that occurs at these points, information technology is very difficult to go on them sealed, and on some boats it is a constant boxing. However, if the shroud chain plates are attached to plywood bulkheads, it is disquisitional that the leaks be stopped and the woods protected. Due to poor blueprint, for many boats information technology is impossible to keep the chain plates sealed completely, only there are things one can do to reduce the leakage and keep the plywood from rotting.

I of the nearly common mistakes that boat owners make is to caulk these points with the wrong material, most frequently polysulphides or silicone based caulks. These materials will non do the job considering they accept poor adhesive qualities. To create a strong, long lasting seal at a chain plate that is subject field to working, 1 needs a strong, resilient adhesive. Such as the dreaded 3M 5200. Gunkhole owners frequently tell me that they hate using the stuff because it'southward messy, and because once applied, it'south very difficult to remove or detach parts bedded with it. Merely that is precisely why it should be used; 5200 is one of the strongest adhesives available and adheres very well to metals and nigh all other materials other than some vinyls and polypropylenes. Polysulphide "sealers" are not expert adhesives and silicone is not an adhesive at all. It'southward primary ways of adhesion is suction. That's why you can glue glass together with it, but nil else, for only glass volition yield a perfect suction surface. If you ever wondered how they can glue aquariums together with silicone, that'due south the reason why.

If your bedding or caulking material does not adhere to a part, though it may appear to cling closely, what we stop up with is a minute crevice betwixt caulk and the mating surface. In turn, this crack becomes a capillary that is capable of transporting water in amazing quantities through a scissure so pocket-sized that it may not even be visible.

Therefore, one of the best means of sealing up leaky chain plates at the indicate where they pass through the deck is to thoroughly clean the fiberglass surfaces, preferably with something like a Dremmel tool with grinder bit to get a expert bonding surface. Don't waste y'all time trying to caulk over a clay laden surface, you efforts to seal will fail. Plus you must exist sure that in that location is no waxy or oily residue. Thus, it'due south best to sand or grind all surfaces to exist bonded.

Oftentimes times the width or length of the rectangular hole is also large to be able to fill information technology in fairly. If that'south the case, you can glue in appropriately sized filler strips with 5200 so as to reduce the gap between the concatenation plate and deck. Once the 5200 has cured, then you can come up back and utilize the final bead of caulk, and bed down the rectangular flange plate if in that location is 1. Considering of the forcefulness and durability of 5200, this method should last for many years assuming that there is non excessive structural motility involved.

If the chainplate is attached to a plywood bulkhead, information technology's a proficient idea to treat the area to prevent deterioration. A successful method I have used is to unbolt the plate, grind down the surface to go it proficient and rough, and so coat the area and commodities holes with epoxy. This volition help shed water and profoundly reduce the potential for rot if the attempts at sealing the leaks are not successful.

Stanchion Bases and Other Hardware

The adjacent nearly mutual source of leakage are those pesky lifeline stanchions. These stanchions are subject to an incredible amount of stress, and so that over time even the best installations will begin to leak. Nevertheless, I see far too many boats where the bones pattern of the base of operations is poor. The foot print of the base is often so small-scale that information technology has niggling or no adventure of providing a stable attachment. If that's the case, the merely option is to alter them out, if possible.

Properly repairing leaking stanchions often becomes a nightmare job considering the gunkhole builder has provided no access from the underside. If you can reach the under side, the task is adequately easy. First, the bases should be removed entirely. Check to run into that the bolt holes are properly sized to the bolts. If the holes are oversized, a rigid attachment cannot be obtained. Correct this by completely filling the holes with epoxy and milled fibers; and then redrill the holes (using a drill guide) to their proper size. Lightly sand the outer surface to remove dirt and mold release compound that may still be nowadays. If the base did non take a dorsum upwards plate, y'all should add together one, infinite permitting. Aluminum or a blank of scrap laminate will piece of work fine. Use the stanchion base every bit a design to drill the holes. Don't apply plywood with nuts and washers as these volition trounce the plywood and allow loosening.

Again, the material to use for bedding stanchion bases is 5200. Both the stanchion base and the support plate on the underside should be thoroughly bedded as this will create a double seal. When pushing the bolts down through the holes, and while the head is standing proud about 1/4", make sure that there is bedding under the caput. If not, add some.

Deck Drainage

I don't know what it is about sail gunkhole designers, but they seem to have a superb knack of overlooking deck drainage. As I make my rounds through marinas and gunkhole yards, information technology's amazing the number of boats I see with water standing on the decks. When hardware is nowadays, leaks are sure to follow, which are also a serious hazard to cored decks. Ane way or another, you have to find a way to provide adequate drainage, whether by notching the rail or installing a scupper.

Ports, Windows and Hatches

These tend to develop leaks because the structures to which they are attached are not completely rigid and are bailiwick to motion, thus breaking the bedding seals. This is often the case with port holes in the sides of cabin trunks. Jumping on the deck well-nigh them results in flexing that breaks the seal. Many boat owners just smear some caulking effectually the exterior seam. All this will exercise is create an unsightly mess, but volition non stop leaks.

The bedding seals in port holes intermission loose because a non adhesive bedding compound was used to set them, commonly because the ports are plastic. The common reasoning for this runs, "Well, these parts are plastic and if I employ 5200 they will never come off without breaking. Therefore, I volition use polysulphide or silicone." That is true, but what you've at present got is leaks, so it'southward your pick betwixt leaks and costly interior harm, and parts that come off hands. It'southward truthful that if you bed a plastic port with 5200, you may end upwards destroying the port trying to get it off. On the other hand, if you utilise 5200 and bed it properly, you shouldn't e'er accept to deal with leaks again.

If the flexing is excessive, at that place will exist essentially no way to terminate the leaks short of reinforcing the flexing area. This is a fairly mutual problem with side decks side by side to trunk cabins, and around hatches set in a wide expanse of deck; if the deck flexes at all, the hatch or port won't stay sealed.

Alternative Methods

Whenever you lot suspect that slightly flexing structures are the primary cause of leaks, such equally hatches on deck or passenger vehicle roof, or port holes in a cabin trunk or even hull side, attempt jumping on the deck or stressing the surface by some method to run across how much information technology flexes. If flexing is just moderate, an culling method of leak stoppage may be appropriate. Instead of bedding and bolting the part down hard with moisture bedding, in which case you squeeze well-nigh of the bedding out, leaving merely a thin flick of bedding that will seal less well, endeavor using this method of creating a gasketed joint, which commonly takes two persons to accomplish. For this method, you can utilise whatever loftier quality flexible caulk rather than 5200.

Cut a number of shims of equal thickness, say 1/8". Employ the bedding thickly and evenly around the mating surface using a putty knife to smooth it out to slightly more than than that thickness. Utilise a new putty knife and wax it so the caulk doesn't stick to it. While you brainstorm to fix the hatch or port frame in identify, have the other person shim it all around. The objective here is to create a layer of bedding of compatible thickness past using the shims and excess of caulk that will serve as a flexible gasket. The thought is that if at that place is structural movement, rather than creating a rigid joint that is going to break loose, we create a more flexible bring together past this method.

Obviously, great care has to be taken that at that place are no big bubbles or voids between the hatch frame and caulking layer. Fix the hatch frame in identify, and press down until the shims stop it. A lot of caulk should exist squeezing out the sides. Next, run all the screws or bolts in, simply practise not draw them tight. Leave enough infinite under the heads that more caulk can be added. Now, allow the bedding to fully cure, at which bespeak you come back , recaulk under the bolt heads, and and then describe them tight. What you accept washed is to create a gasket. If leaks redevelop due to a flexing construction, you tin come up back and retighten the fasteners.

Notation: When retorquing the fasteners, be especially careful with cast aluminum or plastic flange plates; if torqued besides much or unevenly, they are likely to crack or break. Extruded aluminum will not break, but you do run the risk of distorting the flange if torqued too much or unevenly.

Windlasses

These are another common leakage problem. Considering the leakage occurs within the rope locker where leaks ordinarily exercise not cause interior h2o impairment, the leaks often cause astringent damage to the windlass drive motor and housing. Windlasses usually develop leaks because they are highly stressed, breaking the seal around the deck and bolts. If yous don't already have leaks, you tin can usually avert them by being conscientious not to place very heavy loads on the windlass. Don't use it to force out stuck anchors.

There is only one solution for curing leaks around the windlass base, and that is to pull it and rebed it. Not a pleasant task, only keep in mind that only smearing some caulk effectually the base won't aid. Very often, I find that the real crusade is that the builder failed to provide an adequate foundation for information technology during construction. In other cases, the architect cored the foundation area with plywood, but the windlass installer failed to thoroughly caulk the bolts with 5200 and water got into the plywood and rotted it. Whatever the cause, yous need to evaluate the source of the problem and right it.

Leaking Packing Glands

Information technology is oftentimes a bully mystery to boat owners why they suffer from chronic packing gland leakage subsequently repeated repackings and tightenings. Some attempt converting to the "dripless" type of glands and still that doesn't solve the problem.

Chronic packing gland leakage is usually the issue of excessively flexible engine mounts on diesel fuel engines. Considering pocket-sized diesels crusade a lot more vibration than larger diesels, sail boat builders prefer to use softer mounts which let for more than engine motion. Engine movement, of class, causes shaft misalignment which, in plow, causes packing glands to leak because the shaft is spinning eccentrically and wears the packing out more apace on one side. This, in turn, unremarkably results in rapid cutless bearing vesture which results in even more than shaft motion, at which signal even freshly repacked glands won't end the leakage.

Plain, there is no particularly good solution because yous will have to merchandise off higher vibration levels with stiffer mounts to accomplish less leakage. Any you do, don't switch to an expensive dripless blazon of gland because the shaft misalignment caused by flexible engine mounts will damage information technology and it will be a wasted effort. If the engine mounts are very old, say ten years or more, it'southward a good idea to supercede them. Replace cutless bearings at the point where you can move the shaft in the bearing.

Shaft concentricity can exist easily checked without the utilise of a dial indicator. If the shaft is dirty, clean information technology off with sandpaper while it is rotating until y'all get a overnice, shiny surface. A shaft that is running out of true every bit little as 0.010' is plainly visible. At 0.020" out of concentricity is unmistakable and at 800RPM you will notice the wobble. If so, you need look no further equally to why you accept leakage problems. But why is it wobbling? Is information technology a aptitude shaft, or the result of engine move?

A skilful way to find out is to directly observe how much engine move or vibration is occurring. This, besides, is commonly plainly obvious. Cheque this at various engine speeds. Usually the largest amount of movement volition occur within the lower half of the RPM range, and tend to go away at higher speeds. If the shaft is bent, the eccentricity will become a mistiness just not go away. The potent vibration will increase. If y'all put your hand on the stuffing box, or the transmission, you lot will feel it. If the wobble smoothes out and the vibration tends to lessen, and then the shaft is not aptitude and the mounts are the probable culprit.

If the engine mounts testify to be also flexible, it's a adept idea to alter them out to a more rigid type.

Thru-hull Fittings

With today'due south modernistic materials and cored hulls, leaking thru-hull fittings is not a problem in and of itself. But it is a problem that threatens water intrusion into cored structures of all types, including decks.

To eliminate this danger, it is merely necessary to adhere to a very uncomplicated dominion: Never, but NEVER install a through hull fitting or fastener directly into or through a cored structure. Too, never install a through hull on a surface with a pronounced curve. Otherwise, it will no seal properly, or, if you draw it likewise tight, information technology will cause a dimple in the hull skin. The proper method of ensuring that water never gets into a core is to never alienation the core. When information technology comes to through hull fittings, peculiarly if you have to add ane, this is non as difficult proposition every bit it may seem, though it's a bit more time consuming than for a non-cored structure where yous just drill a hole and popular it in. The unabridged chore takes almost four hours over ii days, not including time to obtain materials.

The first affair is to remove the core from the immediate area where the sea cock or whatever will be installed. This is done from the interior. Let'south say, for example, that y'all are going to install a sea cock that has a 2" diameter foot impress. You'll need to remove about a 6" square of inner laminate and core. In that location are a variety of means to practise this, depending on working space available. Commonly a dice or bending grinder with abrasive cutting disc will piece of work fine in tight spaces. Cut through the inner laminate only and remove the square of inner skin only. Next, cut out the core with a knife in a round shape. The reason for this is that is necessary to relaminate and completely seal up the exposed areas of the core. It's a lot easier laminating the rounded corners than it is a square one.

Next, using an lxxx dust grinding pad on a very modest grinder, you smooth out all surfaces in preparation for closing up the exposed edges, keeping in mind that the laminating surfaces must be admittedly clean, and the bottom of the hole must be flat.

There are several ways to finish upwards here. The method I prefer is to use a high quality marine epoxy paste and two or 4 oz. Material. Don't employ mat because you'll end upward with a big mess. Trowel the paste heavily onto the edges of the core, working it into the cells and rounding out the corners at the bottom. Utilize more rather than less epoxy. Information technology will help to round over the acme corner of the expose cream. So I cut the cloth to the appropriate size -- meaning about a 1" overlap each onto the inner pare and outer pare, so press these strips into the wet epoxy completely effectually the circumference of the cutting out. Following this, you then trowel the remainder of the epoxy paste onto the outer side of the fabric, making sure that there are no holes or gaps, and then smooth information technology out. I employ latex gloves and smear the epoxy around with my fingers. Notation here that you must use fresh two part epoxy for this job, not sometime stuff that has become thick and strong.

This method will ensure that there is no chance that h2o volition leak into the core, because you take completely sealed information technology off. One time information technology's cured, come back with the grinder and smooth out irregularities. At present you're near prepare to drill your hole for the new body of water cock and install it in the usual mode, but there is another important particular to attend to. That is providing a doubler block under the sea cock so every bit to relieve strain on the outer peel.

What to use for the doubler? Well, the ideal material would be a piece of fiberglass laminate scrounged from a boat m or trash tin can. Or any other blazon of reinforced plastic that is one/four" to 1/2" thick. The doubler should be most 1" larger than the foot print of the sea erect and be completely flat. It'southward best to bed this in place with epoxy, let information technology cure, and and then drill the hole through both parts at once to get the best fit. At present you're ready to install the sea cock and never have to worry well-nigh it leaking.

Posted Dec 23, 2000

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