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Posted by on May 10, 2011 in Maintenance, Outboard Engines, UK, US | 4 comments

Outboard Motor Corrosion Control

WIres to nowhere on your outboard? Don't just cut them off—replace them.

Question: As I prep my boat for the upcoming season I’ve noticed some small gauge wires on my outboard engine that are broken. The wires I’m talking about are like the one shown in the picture and they seem to connect some of the parts on the bracket with the lower unit of my outboard engine. Several of these on my engine are broken and just dangling there. Is this a big deal, or should I just cut them off and forget about it? They don’t seem to make anything electrical work.


Linking wires like this one play a vital role in reducing corrosion on an outboard's lower unit.

Answer: The wires you are referring to are extremely important in helping to control corrosion on the lower unit area of your engine. Don’t just cut them and forget them, replace them! These little wires are actually bonding wires that help to electrically connect articulating components on your engine for the purpose of making sure there is a solid electrical connection between these moving parts and any sacrificial anodes located on your engine bracket and lower unit housing. These wires are available all pre-made at your engine dealer and are not too expensive. Get new ones and replace the broken ones immediately. Don’t forget to replace any depleted anodes on your engine while you’re at it.

—Ed Sherman


  1. Don’t just leave it there like it was nothing. That’s a very important wire and it should be replace immediately.

  2. Good tip Ed. Making sure you sacrificial anode is properly connected will ensure you outboard lasts a lot longer.

  3. Use some heavy grease on bolts and nuts while connecting new wires – it’ll help prolong time between maintenance.

  4. Yes, it’s important to replace the wire immediately. Corrosion contributes to the failure of any metal that it starts to consume. Therefore, proper and enough protection of metals from corrosion help the equipment and structures to last longer and look better.