forgot your login?

Prop Strut Zinc Anode

Part #: Z5074
Zinc anode sized specifically for struts used on Catalinas. Although the struts are made from military grade 70 manganese bronze they contain about 25% zinc and should be protected by a zinc anode if in salt or brackish water or if in a marina that is "hot" with stray electrical current.
A zinc anode helps prevent "bleeding" where the iron and zinc in the bronze alloy migrate to the surface making the bronze appear pink. This weakens the bronze and the strut must be replaced.

To offer any protection to the strut, the zinc must have a good electrical connection to the bronze. Most zinc anodes rely only on the bolt for this connection. Our zinc anode includes a special cast in bushing. It’s sharp inboard end creates and maintains excellent electrical contact with the strut. Without this bushing the contact between the bolt and the strut can degrade in as little as three to four weeks.
• Outside diameter: 2-13/16"
• Thickness, each zinc: about 1/2" or total thickness of about 1"
• Through bolt: 5/16-18 x 1-1/2" (included)


Strut Installation Methods & Typical Modes of Failure
Catalina employed different strut designs and mounting methods over the years. This article describes those designs and methods to aid in the understanding and repair of your boat.