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Maintenance

Maintenance

The Devil Is In The Details

Knowing what kind of corrosion can be present aboard will help save your boat from disaster.

By Capt. Ken Kreisler

Great floods have flown from simple sources.” So said William Shakespeare and is a fitting opening for our conversation on the potential negative effects of corrosion aboard your boat and the possibility of big troubles because of it. How big? Great floods indeed.

Let’s jump right into this by getting a few facts straight. Steering clear of any chemistry

This kind of damage, and much more, can occur when your underwater metal is not protected.

lesson, electrolysis involves only one metal and a major change occurring in an electrolyte with chemical properties that make it capable of conducting an electric current. A good example would be when a lead-acid battery discharges and produces a significant alteration in the concentration of the battery acid.

So when, years ago, one of my dock mates called me on the VHF asking for a tow, he was wrong when he stated, “Electrolysis caused that blade on my prop to weaken and finally break off.” No shipmates, his problem was most likely brought about by galvanic corrosion or, in part and sometimes in collusion with, its equally evil relative, stray current.

With galvanic corrosion the deterioration occurs between the dissimilar metals as they react while immersed in salt water. This is caused by the current—the movement of an electric charge—that flows between the two, each acting as anode or cathode, depending on its place on the galvanic chart of metals in sea water, and as a result of either being physically or electrically connected.

The easy-to-read galvanic chart.

The easy-to-read galvanic chart.

The long and short of it here is not so much with the why of the process but more of preventing the result. For example, my buddy’s bronze propeller blade gave up more of itself, corroded as it were, then let’s say the stainless steel shaft it was attached to because it is a less noble, or more reactive metal than that of the shaft’s material.

While the effects of galvanic corrosion will more than likely occur over a protracted period of time, the serious effects of stray current can be seen in as little as several days. Should you have, for example, some faulty wiring lying in the bilge or a damaged float switch sending current into the water, or the same condition existing on another vessel in your marina, and even with issues from the dockside shore power, regardless if you have a galvanic isolator in use, your boat is in serious danger. A shaft, rudders, props, outdrives, lower units, and bronze through hull fittings are all at risk.

If you even suspect this may be the case, and unless you are an ABYC certified marine electrician, the best advice is to take a big step back and get the experts in post-haste. (www.abycinc.org/educationprograms/certificationDirSearch.cfm)

The all too familiar bolt-on zinc anode is necessary for protection against galvanic corrosion.

The all too familiar bolt-on zinc anode is necessary for protection against galvanic corrosion.

Protection against galvanic corrosion is a bit simpler and yet comes with its own set of rules. “With fiberglass boats, Mil Spec A-18001K Zinc alloy sacrificial anodes are most suitable for the saltwater environment if the underwater metal you are trying to protect is bronze, stainless, and Nibral,” said Bob Olsen, President of BoatZincs.com. “With brackish water, aluminum anodes (Mil Spec A-24779), which also provide saltwater protection as well, work best. “If you use your boat only in freshwater, magnesium anodes (Mil Spec A-21412) is what you will need.” If you run a stern drive or outboard boat, use aluminum protection. It’s best to check with your manufacturer for any special needs. In addition, with inboard engines, always make sure to check your pencil zincs twice a year.

The size of the anode is a function of how many square feet of metal is being protectedmil-spec and if you are re-zincing, make sure you confer with your yard or marina service manager. “And but for a few situations, you cannot over protect your boat,” Olson added so feel free to collar your shafts as well as long as your boat is properly bonded. Any questions on this, call in the right technician to have a look.

Making sure your boat’s metal fittings are properly protected against both galvanic and stray current corrosion is one of the most important preventive maintenance regimens aboard your boat and one you should always be aware of.

For more information, please contact http://www.boatzincs.com

 
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Posted by on May 1, 2014 in Maintenance

 

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Maintenance

Maintenance

Like Running On Empty

Taking precautions to get your fuel system and engine room squared away, whether on a day trip or spending time away in foreign waters, can help prevent breakdowns, costly repairs, and a ruined vacation.

By Capt. Ken Kreisler

On the subject of our country’s energy problems, investigative reporter and Pulitzer Prize winning journalist Russell Baker was quoted as saying: “Is fuel efficiency really what we need most desperately? I say that what we really need is a car that can be shot when it breaks down.”

That’s a sentiment those of us who have had problems with fuel-related breakdowns can relate to. It is an all too familiar feeling as we stare, with deck hatches akimbo, at that inanimate hunk of metal and hoses and wires and begin spouting, justifiably so, the proper salty and appropriate epithets.

Cap'n Ken at the helm

Yours truly at the helm on a day where everything went according to plan. Regardless of your time away from the dock, taking the proper precautions with some basic preventive maintenance measures can and will ensure a splendid time is had by all.

During one of my many extended forays away from the dock and outside of U.S. waters, I was at the helm, tanks just topped, and enjoying the mild conditions of the sunny passage back home. Totally content and in harmony with the familiar and slightly hypnotic rhythm of the twin diesel rig under my command, I had just checked the info on the GPS unit—43 miles to Palm Beach inlet—when I heard the timbre of the port engine change. And then the resonance of the starboard dropped as well. Quickly sitting up, and no longer enjoying the aforementioned feeling of nautical bliss, I clocked both gauges and immediately noticed a drop from 1900 to 1500 to 1000 to a quivering 600 rpm to a dead stop. It was all hands on deck for my two crew members and me.

Using an external funnel such as this one from Shurhold right from the pump, can often trap dirt, water, and other contaminants from getting into your fuel tank.

Using an external funnel such as this one from Shurhold right from the pump, can often trap dirt, water, and other contaminants from getting into your fuel tank.

That well-known three-hour cruise had turned into an all day constant travail of draining the Racors and changing both gunked up secondary and primary filters until finally limping back into the inlet and our dock at the Sailfish Marina. A day later, I was still at the filters, trying to get all the water out of the tanks. Not fun.

Taking on a load of dirty and water-laden fuel can all but ruin your well-planned travels. But just like downing a Prilosec as a preemptive strike before that night of gastronomical fireworks with your favorite uber spicy foods and drink, so can taking the right steps with your fuel and fuel system make sure you cut the odds against experiencing a mid-travel breakdown in your favor.

Before setting out, always remember that no matter where you fuel up, there is going to be some sediment, water, and mystery stuff present. It’s the nature of the beast. From refining to either gasoline or fuel oil, until it’s stored, shipped, stored again upon delivery, and finally pumped into your tanks, it has had plenty of time to play host to a veritable cabal of evil doers.

If you have the space in your engine room, you may want to research some of the offerings from Algae X.

If you have the space in your engine room, you may want to research some of the offerings from Algae X.

High on the list is water. While life as we know it could not exist without it, once inside your fuel tank, it can wreak havoc with both diesel and gasoline engines. How does it get there? Carefully check your fill cap for leaks or a compromised deck seal. Condensation can also exacerbate the problem as regular heating and cooling can cause moisture to form in the tank’s air void. Best to keep fuel tanks topped off on a regular basis.

Algae and fungi growth are the other culprits. Feeding on both fuel and air, these malicious microorganisms can easily gunk up your filter elements and stop you dead in the water. While there are many biocides on the market, avoid those with alcohol as this can cause damage to many rubber parts in the system. And remember, if you use a biocide, the resulting ‘body count’ can add to the already soupy mix on the bottom of your tank and those churned up while underway or in rough conditions. Take extra caution when monitoring your filters.

Having a primary fuel water filter is often your first line of defense against allowing water to get into your engine.

Having a primary fuel water filter is often your first line of defense against allowing water to get into your engine.

On that note, your first line of defense is to carefully check the ubiquitous primary fuel/water separator filter. Racor is most popular but there are also units manufactured by Dahl, Separ, Fram, Groco, and a host of others. Drain any water and sediment out of the bowl and check and replace the filter element as per your engine manual. Or, as most seasoned travelers say: When in doubt, swap it out. Don’t forget to check your secondary filters as well and always carry several spares. If you are a regular cruiser, you might want to check out Algae-X’s offering of fuel conditioning units or a more advanced fuel polishing system.

If you want to take an extra ounce of prevention, try using an exterior filter during fill ups such as Shurhold’s Mr. Funnel. This portable unit is used to catch impurities right from the pump as the fuel is going into your tank. While it will slow your fill time, if you are away from a reputable marina, it can help.

Finally, on the fuel system topic that is, and again, depending on how you use your boat, you may also want to give your fuel tanks a cleaning every once and a while, especially if you are changing those filters a bit too often. Get a reliable mobile company to come dockside to take the appropriate sediment samples and properly polish your fuel.

Using oil absorbent pads, such as these from 3M, can help keep your bilges oil free.

Using oil absorbent pads, such as these from 3M, can help keep your bilges oil free.

Now, let’s discuss your engine room. What could be worse than setting out for a day away from your home dock or on that extended and long-planned voyage to the Bahamas, and having problems with something gone terribly wrong down there? Compounding the dilemma is the afterthought that, with a bit of preventive maintenance, it could have been avoided. Here are a couple of engine room tips and thoughts to help cut down the chances of something stopping you dead in the water.

To begin with, clean your bilges and dispose of any oil-laden material with your marina manager. Once done, and if you already do not do this, position a couple of oil absorbent pads under your engine(s) so as to not only catch any oil drips, but to see if there is a problem with any suspect oil leak. And as any leaking water from the raw water system or expansion tank will also show up, this will help in identifying where the problem is. It’s also a good idea, especially when setting out on a long trip, to and make sure you carry enough oil and filters to do one complete oil change. In fact, make that two. As one old salt used to remind me: “Y’can’t get out and change a flat kid,”

Keeping both bilge pumps and float switches free of debris is an important part of your preventive maintenance regimen.

Keeping both bilge pumps and float switches free of debris is an important part of your preventive maintenance regimen.

Check your sea strainers for any fouling as well as any possible blockages to thru-hull connections, especially those to the air conditioning and raw water intakes; examine the hoses and clamp connections for any signs of degradation; and give all your seacock handles several open-and-close shifts. If you see any signs of wear and tear on any of these, replace them immediately. And make sure all your bilge pumps and float switches are free of debris and that bilge alarms are operating properly in both auto and manual modes.

Examine your internal main engine and genset zinc anodes for wear. If they are even half gone, replace them. Also, give those on your hull and running gear a look-see as well.

Let’s hope that another Baker witticism is not in your future voyaging plans: “The goal of all inanimate objects is to resist man and ultimately defeat him.” Safe travels everybody.

If you have any maintenance tips or a first-hand account of trouble along the way, use the COMMENT link on the bottom right corner below and send it on in.

 
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Posted by on April 12, 2013 in Maintenance

 

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