Editors Note: The following has been printed courtesy of Pier & Waterfront Solutions (PWS) of Door County, WI.
Boat Lift Cables Require Maintenance
Boat Lift cables, along with the winch on your lift, are the (2) most important components of a boat lift. As a result, they require periodic attention. Remember, these (2) pieces do all the “work” on your lift. They do the lifting by raising the rack assembly with the weight of the watercraft on it. Lift cables allow your boat, pontoon or PWC to be raised and lowered when you need them.
The lift cables are made of either stainless or galvanized steel.
Both types of steel offer the benefit of corrosion resistance and strength. But there are some noteworthy differences that you need to pay attention to if you are deciding on a new or used lift or just plain replacing the cables.
You need to look at the available options and be able to do simple maintenance on either type of cable. With your owner’s manual, the correct part number, weight capacity, and type of cable should be listed. If it is not listed, or you do not have an owner’s manual, you can contact PWS to get assistance in determining what cables your lift requires regardless of the brand.
Types of Steel used as Boat Lift Cables
Galvanized Steel: Galvanized steel is a carbon steel made corrosion resistant by the application of a thin layer of zinc oxide. This is accomplished through a “hot dip” in a zinc bath. The process applies a thin layer or coating of zinc to the steel to increase the metal’s resistance to corrosion.
Galvanized steel is less expensive than stainless steel due to the differences in the processing of each. Galvanized steel is strong and each cable is made to handle the loads created by your boat lift. The downside to galvanized steel is the fact that it has a higher electron-potential than stainless steel, making its’ corrosion resistance less effective because it does NOT regenerate when damaged.
Stainless Steel: Stainless steel is carbon steel which is mixed with about 10% chromium to resist oxidation or corrosion. The chromium in the steel forms a thin layer of chromium oxide that promotes resistance to corrosion. When exposes to oxygen the protective coating WILL regenerate. The anti-corrosion of the chromium simply oxygen to maintain this property of resistance.
Getting technical now
Galvanized steel boat lift cables, although corrosion resistant, are more prone to wear. The zinc layer can be scratched or cracked through expansion and contraction. This can lead to spot rusting and a decreased life of the steel cable. The scratching occurs when a cable rubs against itself as it winds around the winch drum. Each layer is going at a slightly different speed than the layer below it – thus scratching the zinc coating on the cable.
Even internally the strands in the cable are rotating at a different speed and the zinc will be damaged. This can be frequently seen on the upper areas of a galvanized cable where it enters the winch. It also frequently occurs on the bottom layer of a cable where it is wrapped around the drum on the winch.
Stainless steel boat lift cables, on the other hand, are blended with chromium oxide during manufacturing. This makes its corrosion resistance regenerative in freshwater.
Rusted Boat Lift Cables
You will see lift cable corrosion most commonly in the form of rust.
Galvanized steel cables will corrode over larger areas of its surface while stainless steel cables seldom rust. The addition of chromium to the steel during the production process creates a product that is regenerative and uniform in resistance throughout.
Whereas galvanized steel, with its zinc coating, does not regenerate and when damaged exposes the steel beneath to the elements. The rusted areas are more prone to fraying and breakage too.
In Conclusion …
Follow these Maintenance Suggestions for your Boat Lift:
- In spring and fall (and at least once during the summer months), put a short blast or two of PENETRATING OIL on the cables wrapped around the winch drum from the top of the winch. Do not soak the cable, you’ll contaminate the water below. DO NOT use any oil except penetrating oil. NEVER USE GREASE (it traps the moisture inside the cable accelerating it’s deterioration).
- Inspect cables for frays and rust – Caution – wear leather gloves to prevent injury to your hands. Check near the top of the winch cable as this is the most common area for frays. Replace as needed, if corrosion is present.
- Check all cables to make sure they’re aligned properly on the pulleys
- With your watercraft on the rack – check for any slack in the cables. All cables should be equal in tension.
- Look for cable corrosion near the winch with the rack fully down (but without slack in the lifting cables.)
- If the canopy cover is on, are all the springs or bungee cords secured? Broken hardware should be immediately replaced.
- Check bunks and guides to make sure the hardware is secure.
- If carpeted, replace torn bunk and guide fabrics to protect your boat hull. Consider replacing carpet with vinyl bunks.
- Exterior wheel driven winch? Check the bungee cord to see if it needs replacement. Cracked cords can break at any time so be sure to use the correct cord.
- Don’t ignore your dock – check the bolts.