Ten Problems That Can Stop You Cold 7) 8) 9) 10)

[Electronics Guru]

ADVERTISE HERE

7. Hose Clamps, Connections, and Hoses
If you have faulty or improper hose clamps, water can work its way into or out of your pumps and engines. Keep in mind that not all hose clamps are created equal, and the stainless steel that the clamps are made of comes in a range of grades. For maximum protection, use 300-series stainless steel hose clamps and make sure the screw inside the clamp is also made of 300-plus-series stainless steel or plated carbon steel to prevent rust and corrosion. But be careful. If the clamp band is of proper-grade stainless steel, but the screw inside is not, the screw will rust and the clamp will loosen over time, allowing leakage. Marine-grade clamps are usually designed with 316 stainless steel


8. Electrical Connections
Using the incorrect type and gauge of electrical wire or improperly sealed connections can lead to potentially catastrophic problems onboard. The marine environment is extremely harsh on wiring, and moisture will penetrate any unsealed connection. Furthermore, corrosion is the number one cause of electrical failure and can lead to an onboard fire, so choosing the appropriate wiring and sealing all connections is essential.

To begin, never use solid wire, as it will eventually crack or fray. Many boaters use copper wire, but even that is a no-no; copper will corrode over time, resulting in a heat buildup that can cause a fire. Instead, opt for marine-grade “Type 3” strand, tin-lined copper wiring for maximum protection against corrosion and electrolysis. According to Paul Esterle, who writes and lectures about marine maintenance and has his own maintenance column in Voyaging, Ancor’s primary boat cable is a good choice, as it’s made to American Wire Gauge standards and reportedly has up to 12 percent more tinned copper conductors than SAE wire. In addition, the company’s boat cable exceeds all Underwriter’s Laboratories and American Boat and Yacht Council (ABYC) standards and is available at most marine stores nationwide. Also remember to use the proper gage wire.

Nearly all wiring problems occur at the connection, so never twist wires together to make a connection, don’t wrap a bare wire around a terminal screw, and avoid using wire nuts to secure connections or make splices. Although wire nuts are quick and easy to install, they eventually loosen, can admit moisture and therefore cause corrosion, and are not acceptable under the standards set by the ABYC.



9. Bedding Compounds
During spring commissioning, when you’re normally adding new equipment to your boat, you often need to seal any mounting holes with bedding compound or caulk. It’s imperative to apply them correctly the first time. If you do, you can almost forget about them. That’s because modern bedding compounds require no maintenance after they properly cure. Poor surface preparation and improper application may result in leaks. We spoke with technicians at 3M and Boatlife, both manufacturers of marine sealants, and found that while it’s difficult to generalize about the properties of all bedding compounds, most share some universal dos and don’ts.

Preparation should always begin with roughing or scoring the surface, then ensuring it’s clean and dry by wiping it thoroughly with a nonalcohol-based solvent. Alcohol contains many of the same elements as water and will therefore disrupt the natural curing process of a moisture-cured system.

Apply bedding compounds sparingly and never in globs. Cover just a little more than the area you intend to bed; after curing, the sealant will shrink. A proper bead of caulking should not be less than 18 inch wide and not more than 12 inch wide. After applying the compound, loosely secure the pieces to be bonded with bolts or screws until the sealant becomes dry to the touch, then mechanically tighten the pieces.

Marine sealants are usually moisture-cured, which means they not only need moisture but also time to properly harden. Cure time can take anywhere from 24 hours to 20 days depending on the sealant used and relative humidity in the air, so it’s important to read the directions. And don’t rush to launch. Never launch your boat until all sealant has completely cured.

Once the compound has cured, there are a few things you can do to extend the life of the sealant. Exposure to strong solvents, oxalic acid (i.e., two-part teak cleaner), and industrial cleaners may break down the sealant over time. More likely, ultraviolet light will break down bedding compounds; signs of this are yellowing or a chalky residue. To remove damaged material, vigorously rub the affected area with the proper solvent or a mild abrasive until the discolored layer disappears. Reapply with the same-type sealant as before if necessary.



10. Shaft Alignment
The effects of a bent propeller shaft are not always as apparent as one might think. Only a few thousandths of a degree will wear struts, couplings, and bearings and put stress on your vessel’s transmission and mounts. Intense vibration throughout the hull can occur well after these components have been damaged, and therefore checks should be done before this occurs. We called Bradford Marine in Fort Lauderdale, Florida, and spoke with Ken Spaulding, the assistant foreman in the machine shop, to find out how he checks for a bent shaft.

Once the prop is removed, a dial indicator is used to give measurements at the transmission coupling and three places on the tapered end towards the prop. With each measurement, the shaft is rotated 360 degrees. A measurement of more than five thousandths of an inch constitutes an unacceptable amount of wobble in the shaft, and the shaft will either have to be trued or replaced.

Fortunately, you can check your boat for a bent shaft without such precision equipment. Clamp an ice pick or sharp screwdriver into a stand-alone vice. Position the tip against the underside of the shaft, just behind the strut. Rotate the shaft by using the prop for leverage, and look for gaps or gouges. It’s no dial indicator, but it will help you zero in on a bent shaft when troubleshooting the source of your boat’s vibration.
In addition, double up on clamps everywhere below the waterline and at other critical connections (but don’t make room for two if there is not enough barb!). Check all clamps periodically, and tighten them as necessary—but be careful not to overtighten them, as they can break or damage the hose when components expand due to heat.

All hosing—especially that for mechanical gear, fuel, and hull penetrations—should be inspected for cracks, softening, hardening, or other signs of service wear. If they show any of these signs, replace them.