Nothing lasts forever – including boat lift cables

Boat Lift cable problems require a thorough explanation.

There are two types of normal cable wear:

  1. Internal cable abrasion- This occurs whenever strands work against each other under load.
  2. External abrasion – This will occur when the cable bends around the winch drum and rubs against the adjoining cable wrap.  It also occurs when the cable rubs against the side of the winch drum
image of frayed lift cable

Frayed Boat Lift Cable

Types of Steel used as a Boat Lift Cable

Galvanized Steel: Galvanized steel is carbon steel made corrosion resistant by the application of a thin layer of zinc oxide.  A “hot dip” in a molten zinc bath results in galvanizing the cable. 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 stronger than stainless steel. 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 forms a chromium oxide layer that promotes resistance to corrosion.  When exposed to oxygen the protective coating WILL regenerate.  The anti-corrosion of the chromium merely needs oxygen to maintain this property of resistance.

All Lift Cables Will Require some Maintenance 

The winch and lift cables require periodic attention. Remember, these (2) items do all the “work” on your lift.  They do the lifting of the rack assembly with the weight of the entire boat and motor on it.

Boat lift cables are manufactured out of either stainless or galvanized steel.

Galvanized cable is used as the winch cable on heavy boats.  Stainless steel cables are used for the remaining cables on top brands like ShoreMaster.

Both types of steel offer the benefit of corrosion resistance and strength.  However, watch for the noteworthy differences mentioned above that require your attention.

Corrosion

Galvanized cables that break usually show signs of corrosion or rust in advance. Typically, the failure is located near the winch when the rack is in a lowered position.  Another common site for corrosion is at the bottom of the cable where it secures to the frame on some brands.

image of Rusted Boat Lift Cables

Rusted Boat Lift Cable

A slight discoloration indicates that the protective galvanizing coating may have worn away. Heavy concentrations of rust indicate that the steel cable is losing strength and requires replacement immediately.

How long should a cable last?

Experts claim galvanized cables require replacement every two years.   All things being equal, a stainless cable will last up to twice as long.

A point often overlooked – internal abrasion or rust is hidden and may not show external damage on the cable during a visual inspection.   A boat lift cable like this may sometimes fail without prior warning.

Other causes of cable failure

An improperly positioned boat puts extra strain on any boat lift cable. Wave action pounding against the boat hull or jamming the rack against the frame may send your boat into the water with a corroded or damaged cable.  Even a new cable may “snap” if you jam the rack against the frame.

When in doubt, replace the cable; trying to squeeze another year out of a $95 cable that you know s damaged or rusting isn’t worth the risk.

In Conclusion… What Can You Do For Your Boat Lift Cable?

  1. In spring and fall put a short blast or two of PENETRATING OIL on the cables.  Spray the cables wrapped around the winch drum from the top of the winch.  Do not soak the cable; you’ll only contaminate the water.  Use only penetrating oil.  A quick spray during the summer is very helpful.
  2. NEVER USE GREASE to lubricate the cables. (grease traps the moisture inside the cable accelerating its deterioration).
  3. 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.
  4. Check all cables to assure correct alignment on the rack pulleys.
  5. With your boat correctly positioned on the lift, check for any slack in the cables.  All cables should be equal in tension.  Contact PWS for adjustment, if needed.
  6. Look for cable corrosion near the winch with the rack all the way down.  Maintain weight on the rack to assure proper tension on the cables.

We hope that this article will make your life easier and lend more confidence to your selections. Your boat lift is an investment, and as such we want to help you make wise decisions.

Reminder

PWS is located in the center of Door County at 7325 St Hwy 57.  It is located 1 mile North of County MM (Hwy 42) and South of Sturgeon Bay.  Look for the intersection of Idlewild Road.  

Want us to address a dock or boat lift topic for you?  Feel free to give us a call.  

Call Jerry at 920-493-4404 or Email Jerry@wisconsinpws.com for more information.