January 29, 2013
In the boat and yachting electrical world, it is not enough to merely strip the insulation off the end of a wire and wrap it around a screw that gets tightened. Wire terminals are the approved method of connecting wire ends to the source of electricity and to electrical devices that require it.
Marine wire has specific qualities that make it superior for use on boats and yachts. Marine wire should be finely stranded copper, for flexibility, as marine wiring must be able to survive long periods of vibration without failure. The individual strands making up the wire should to be tin plated to resist corrosion. The wire insulation must be able to withstand the heat, moisture, salt, fuel, oil, acid, and abrasion which are usually present in this harsh environment.
Marine wire terminals also should be made of copper, and have tin plating for corrosion resistance. Marine wire terminals should be insulated and of the crimp-on type electrical connection.
The wire terminal must be selected to match the size (gauge) of wire being used. In the smaller wire terminal sizes, the terminals are often color coded, RED for 22-18 ga., BLUE for 16-14 ga., and YELLOW for 10-12 ga. Always use the correct sized terminal for the wire gauge being used.
When using ring terminals, always select the correct ring terminal for the size of the fastener used to attach the terminal. It is important to maximize the surface area between the terminal fastener and the wire terminal itself to improve the current carrying capacity of the wire and terminal connection. A 3/8” ring terminal attached to a #10 screw doesn’t allow much surface area for the current to flow and has little resistance to bending or vibration. It is possible to modify the size of the ring terminal on some of the larger sizes. A 2/0 x ¼” ring terminal can be drilled out with a step drill to a 5/16”, 3/8”, or larger. However, drilling out the terminal will remove the tin plating on the inside of the hole, which compromises the anti-corrosion properties of the plating.
There are actually two connections that need to be made for each wire terminal. The first is the ELECTRICAL connection, which is made by crimping the middle part of the terminal sleeve to the bared wire strands with the appropriate section of the crimping tool. This section is usually labeled or color coded for the specific terminal size being used. The second is the MECHANICAL connection, made by either crimping the end of the terminal sleeve to the insulation at the end of the wire before the bared strands with the appropriate section of the crimping tool, or by heating the adhesive lined heat shrink tubing around the terminal and wire end insulation.
It is essential to make the electrical crimp connection with enough force to tightly bond the terminal to the wire strands of the bared wire end. There should not be any play or wiggle between the terminal and the wire it is crimped to. It should be very difficult or impossible to pull the wire out of the terminal after it has been crimped to the wire end.
The mechanical connection is important because it moves the strain of flexing and vibration between the copper wire strands and the terminal to the connection of the terminal to the insulation, preventing the copper strands from work hardening and breaking when subjected to vibration and/or flexing.
The mechanical connection may be a second crimp to a crimping sleeve built into the terminal designed to crimp against the wire insulation. This connection uses a different section of the wire crimp tool than the electrical connection section. This section has a larger “hole” when closed, and allows the mechanical sleeve in the terminal to be crimped to the wire insulation without crushing the terminal as much as with the electrical connection crimp.
Another method of making the mechanical connection is with crimp-on terminals supplied with adhesive lined heat shrink tubing. The electrical crimp connection is the same, but the mechanical connection is made by shrinking the terminal heat shrink insulation around the terminal electrical connection using a heat source such as a heat gun or small flame. Be careful not to over heat the tubing if using a flame. Hold the flame about an inch or so below the terminal connection and roll the terminal over the flame to evenly warm the heat shrink tubing. Smoking and blackening is a sign of overheating or heating too quickly. The heat will shrink the tubing to form a tight seal, and when enough heat has been applied the adhesive can usually be seen oozing out from the ends of the insulation. The heat shrink process adds the benefit of very good water protection at the wire termination.
If the terminal being used is of the type without heat shrink and without a mechanical crimp connection, a short length of the appropriate sized adhesive lined heat shrink tubing should be placed over the end of the wire before the terminal is crimped, and heated to shrink around the terminal electrical connection and the wire insulation after crimp has been made. This will provide the necessary mechanical connection to the wire insulation as well as add water protection to the wire end and terminal.
Mark McBride – January 29, 2013
February 14, 2012
The number one reason that drive systems go out of alignment is that the engine mounts are worn or have sagged. The engine sits lower and lower and moves around more so there is increased wear and vibration on the entire drive of the vessel.
Marine engine mounts can make the difference between a low vibration engine, mounted stable in your boat or an iron monster that shakes the hull, produces noise and may lead to damage. Broken, damaged or worn engine mounts are not always obvious when 100′s of pounds of static motor are sitting on the mounts. Excess vibration can be caused by many things, including; mounts that are too soft or hard, worn engine mounts or how the mounts are attached to the bed. Of course, there are other things that can cause vibration, including; misalignment of transmission to shaft, worn components (cutlass bearing, transmission) or damaged components (propeller, shaft, transmission).
The forces of a high revving, high horsepower modern marine engine are passed directly onto the engine mounts. Even small one cylinder diesels really pound the engine mounts. For all their apparent simplicity, engine mounts are subject to a number of forces:
- Longitudinal – The forward / aft motion of the engine
- Lateral – The side to side motion of the engine
- Vertical – the up and down motion of the engine
Most of these forces on a motor mount act in a form of chaotic unison. Not only must the engine hold its own position based on motor and transmission weight, but it also must resist the shearing force of the propeller under thrust. What looks like a simple job for an engine mount gets complex, quickly when throttling up; the engine mounts on one side are ‘stretched’, one the other side they are compressed, they are also subjected to shear by the thrust of the prop. Now add to the equation of a boat throttling up in rolling seas, or depending on the vessel, being subjected to storm conditions or high-speed pounding. The simple combination of metal and rubber that makes up an engine mount sees real abuse in a harsh environment.
Figuring out what engine mount you need:
- Number of mounts. Most marine engine/transmission units use 4 engine mounts, some smaller/older units use 3
- Matching up the weight and horsepower to an engine mount
- Match the Make Model of your engine
Once you know how many mounts you need and a data about the engine/transmission then nearly every modern marine engine can be found with The Engine Mount Cross-Reference Guide. In summary, should you feel that your system has gotten out of alignment, check your engine mounts first. It is the sagging engine that puts pressure on the cutlass and shaft seal and wears them to the point of needing replacement.
January 31, 2012
Marine controls are an essential part of any boat (including auxiliary powered sailboats). After the wheel or tiller, there is nothing else that you touch as much. Your marine controls connect you to the thrust and direction of movement of the vessel whether docking or out on the open water at full throttle. A control may operate the throttle or shift or both; several choices and options are available. Reliability, smoothness, accuracy and response are all features to look for in a marine control.
Shift / Throttle Functions of Marine controls:
Single Function / Single Lever (Controls Only One; Throttle or Shifter) – This is the simple lever that controls just the throttle or just the shifter. Some typical applications are with a Berkley Jet, this lever is the shifter and a foot pedal is used for throttle.
Dual Function / Dual Lever (Controls Throttle and Shift for Two Engines) – This control sees typical use with a twin-engine vessel and offers the simplest to use setup. Like all dual function controls, the lever controls both the shift and the throttle. As you push forward on the lever, the transmission engages and the engine throttles up.
Dual Function / Single Lever (Controls the Throttle and Shift) – By far the most common controller available for virtually every inboard, sterndrive and outboard application. This control is suitable for only one engine. The mounting options for this style control can range from helm stations to the side box controls on an outboard to sailboat cockpit controls. Like all dual function controls, the lever controls both the shift and the throttle. As you push forward on the lever, the transmission engages and the engine throttles up.
Single Function / Dual Lever (One lever controls throttle, the other lever controls shift) – A more traditional approach to controlling the throttle and shift. Some manufacturers do not recommend this type of control because you could throttle up (first) then slam the transmission into forward while the throttle is high! For twin engines, you simple mount two of these. Not for novices and can be dangerous when operated in a panic situation.
Runabout, Outboard or Sterndrive Controls – Smaller boats typically use a side box mount controller, fitted to the right of the helm. With the exception of some jet boats, most of these controls are dual function, single lever. There are specific controllers made for Mercury / Mariner / Force as well as OMC / Johnson / Evinrude. You may be able to use a more generic controller by choosing cables that have end options that work with your system.
Sailboat Controls - Most sailboats use a flush side mount marine control. Older sailboats typically operated with Morse single function / dual lever controls. Most sailboat auxiliaries setup since the 1980′s use the dual function / single lever control to manage the throttle / shift in a smooth fashion.
Inboard and Larger Vessels – These controls are most often binnacle mounted controls that may have two stations (upper helm and lower cabinhouse) and twin-engine setups. The common traditional setup is a single function / dual lever control at the helm station. Owners often want more response and a ‘make sense system’ to help when maneuvering larger vessels with twin engines.
With the right controls, nearly anyone can take the helm* – note that the boat below is not under power!
January 20, 2012
There are four main manufacturers offering replacement throttle, shift and control cables for the boat owner. The choices between these are often small construction details.
Teleflex - Teleflex bought up the original Morse division of control cables. Most boats over 20 years old will have Morse controls and cables. Teleflex has upgraded the original CC series cable to the new design CCX TFXTREME. Teleflex’s unique TFXTREME technology incorporates a patented splined core. Ridges on the core allow a close fit with the cable’s inner liner, but with minimum contact, so the core glides back and forth smoothly like a skater on ice.
The Teleflex TFXTREME control cable was designed because of the original ‘issues’ with traditional marine cables. Traditional cables vary by the stiffness of the core wire and how tightly it fits in the casing. More flexible core/looser fit has an easier feel, but allows more lost motion. This approach leads to an overall sloppy feel, RPM loss or difficult gear engagement. Stiffer core/tighter fit offers less lost motion, but is harder to move. With longer and more complex runs, cable movement becomes progressively more difficult. Thus the classic trade-offs that have existed in control cable design have been resolved with the Teleflex TFXTREME.
Uflex - Uflex control cables are relatively new on the scene, offering some of the most popular OEM control cables in their own high performance design. To reduce the friction the MACH series control cable, Uflex use’s a multi layered core to shield design that allows for high efficiency and smooth operation. The maintenance free cables are wrapped in a long life, high resistance blue outer jacket to offer protection against abrasion, UV and chemicals.
Glendinning - Glendinning has also come on strong in the world of replacement control cables. Glendinning Pro-X cables offer a core which is very stiff while very having a great deal of flexibility is the heart of the Pro-X cable, providing minimal lost motion with high-efficiency. Glendinning builds a maintenance free control cable with a high density polyethylene liner around the central armored core. The entire multi-layer cable is in a corrosion resistant case with protective end seals for long life.
Felstead - Felstead control cables are used in commercial vehicles, agriculture, construction and, of course, marine. Chances are, you handled something using a Felstead cable recently. They are reliable enough for parking brake systems that last the life of an automobile, truck and bus and are rugged enough for use in commercial vessels. Although not tailored for the smaller outboard industry, the 33C, 40 Series and 60 Series mirror the original Morse control cables and are found in vessels everywhere. Long life and smooth operation are assured with such features as rod bearing (the only in the industry) and a sealed, multi-layer cable design.
Ready to buy a throttle, shift, control cable? Check out the Go2marine’s guide to Making Sense of Marine Control Cables.
December 15, 2011
Lasdrop dripless shaft seals are the answer for an easily installed replacement to the original stuffing box on nearly any boat. Once installed, there is virtually no maintenance required. The “Original” Bellows and Generation II models will last as long as eight to ten years before servicing, while the DrySeal model will last three to five years before the inner lip seal must be changed. At the service interval, both the Original and Generation II models would most likely require refurbishing of the seal surfaces. In addition, the bellows on the Original model should also be inspected and replaced, if necessary.
Green Solution - Lasdrop shaft seals are the green solution to preventing contaminated bilge water from entering the ocean you are in. Whether you are running a research vessel in Antarctica, a fishing boat in Norway, a world cruising sailboat or a workboat in Maine, keeping the water you run in clean is a good practice. Remember, keeping water out also means keeping engine and drive train bilge water in.
Lasdrop Shaft Seals are manufactured and engineered entirely in the USA. All Lasdrop products are backed by a three year warranty. Each model is easy to install, requires little or no maintenance, and is sold as a complete kit. Installation is easy and straight forward as long as you can access the area where the seal is installed. It will be necessary to disassemble the shaft from the coupling and the shaft will need to be slid back far enough to remove the original stuffing box.
Lasdrop incorporates injection ports for water lubrication in vessel applications where speeds are over 10 knots. Lasdrop builds single injection port shaft seals from 3/4″ to 1-1/8″ and offers 2 (dual) injection ports installed for shaft sizes from 1-1/8″. Built for any budget and boat, Lasdrop supplies 3 different levels of dripless shaft seals.
Good - the Lasdrop DrySeal is a compact, economical lip seal designed for quick and easy installation. This option offers a lip seal that is in constant low friction contact with the propeller shaft, preventing water from entering your vessel. The simple, affordable solution to a leaking tired stuffing box.
Better - the Lasdrop Original “Bellows” seal is a face seal that features a vibration absorbing bellows, ideal for use on sailboats and workboats. Specially balanced for smooth rotation, this model utilizes a 316 stainless steel and carbon graphite for its sealing surfaces. These modifications and materials result in a dripless shaft seal that lasts twice as long as the Lasdrop DrySeal.
Best - the Lasdrop Gen II is a culmination of more than a quarter century of experience in shaft seal design. An exclusive feature that makes it the premier shaft seal are a unique ball-bearing drive system that allows the seal ring to “float” and remain in constant contact with the carbon graphite seal surface, resulting in a seal that’s impenetrable to water.