Nothing lasts forever—even boat lift cables
There are two types of cable wear:
- Internal cable abrasion—This occurs whenever strands work against each other under load.
- External abrasion—This also occurs when the cable bends around the winch drum and rubs against the adjoining cable or drum.
How long a lift cable lasts depends on:
- How often it’s used;
- What type of cable it is; and
- The care it receives.
Every time a boat is raised or lowered over a winch drum there is internal wear on the cable. Each strand of wire in the winding is moving at a slightly different speed. Abrasion of the cable strands is the result. When you loose too many strands you lose a lot of strength.
What should be done?
Steel lift cables require a squirt or two of penetrating oil occasionally to reduce the internal friction on the strands and individual wires in the cable. This is particularly important on galvanized cables. Lubrication helps to preserve the galvanized coating and minimizes abrasion between strands. Grease should NEVER be used, as it traps moisture inside the strands. Do not saturate the cable and only use penetrating oil for best results. Stainless steel lift cable will also benefit from a few squirts of penetrating oil. This should be done in spring and again in fall.
Strong indicators that a boat lift cable needs to be replaced:
- Excessive broken strands
- Deformities and
- Areas of heavy corrosion.
Galvanized cables that break tend to show signs of corrosion or rust. Usually this is located near the winch when the rack is in the lowered position. It also can be at the bottom of the cable where it is secured to the frame. Note: do not allow the main cable to go “slack” when lowering the rack.
A slight discoloration indicates that the protective galvanizing coating has been worn away. Concentrations of heavy rust indicate that the steel cable itself has lost considerable strength and should be replaced immediately.
Assuming the cable is well cared for, how long should it last?
Experts say that to be safe, galvanized cables should be replaced every two years. All things being equal, stainless cables will last longer—up to twice as long.
A point often overlooked—internal abrasion or rust can be hidden and may not show visible damage on the cable. A boat lift cable like this may sometimes fail without prior warning. An improperly positioned boat shocks from wave action (when bouncing on the lift rack or jamming the rack against the frame) may send your boat into the water.
When in doubt, replace the cable. Trying to squeeze another year out of a $75 cable isn’t worth the risk of dropping your boat or personal injury.
How to Inspect Your Boat Lift Cables for Signs of Wear or Fraying
Anyone can identify a frayed rope. Remember the splitting twine attached precariously to a swing on your ancient childhood play set? With use, rope slowly unravels, and individual strands stand out. The process of wear is natural. However normal, it shouldn’t be ignored. When wear of any kind is noticed on boat lift cables, the issue becomes potentially catastrophic, and usage should immediately cease.
Boat lifting cables—and all wire rope cables in general—wear in two ways: internally and externally (i.e. from the inside and the outside). Below, we examine both kinds of wear, three practical tips to extend lift cable life, and a trustworthy cable replacement resource.
In general, here are a few major signs of damage indicating boat lift cables should be replaced:
- Heavy corrosion
- Rust spots
- Broken strands (especially in excess)
Internal cable wear is less severe than external and is sometimes overlooked. Internal wear occurs when strands work against each other, often under heavy loads, such as when cables are hauled across pulleys or sheaves. Internal wear is caused by nicking and appears almost scalloped on internal strands.
External wear is abrasive and more apparent than internal. Abrasive wear results from metal being slowly worn away over time. What does this look like? The crowns of each wire will flatten, resulting in loss of material. As this occurs, the strength of the cable gradually decreases.
Practical Prevention Tips
- If you own a boat lift, or any equipment employing wire rope cables, you should examine the cables monthly at a minimum. To avoid injury to your hands during inspection, use leather gloves or another form of protection before feeling the cables.
- Using fresh water, lightly rinse your boat lift after each use. Saltwater corrodes cables, reducing lifespan dramatically. A light fresh water rinsing will prevent corrosion and rusting. The rinse will also remove any contaminants and dirt on the outside of the cables.
- Abrasion between individual strands occurs when cables rub against each other. Lubricating your lift cables with penetrating oil, such as Cable Fluid Penetrating Oil, lessens corrosion and reduces internal friction. Avoid using grease, because this substance does a poor job lubricating cables.
Trustworthy Cable Replacement Resource
Keep in mind, you should consider cable replacement every couple of years. Even if only slight wear or fraying is noticed, attempting to extend the life of your cables beyond two years could be dangerous. Do you have a quality source on-hand for purchasing cables regularly?