Electrical systems maintenance  

An essential guide to maintaining your boat’s electrical systems – sail & motor 


Boat maintenance is essential to ensure that your onboard systems continue to perform safely and efficiently. Here are our top maintenance tips for your electrical systems. 

Test the battery system 

close up of electrical system batteries

The battery system is the heart of your boat. Whilst afloat, you’ll rely on your batteries for light, water pumps, starting the engine and much more. Periodic battery tests are an essential part of boat maintenance and its good practice to check your batteries throughout the year to ensure that all parts are in working order. 

Prior to examining, disconnect all the terminals from the battery and make sure you have unplugged your mains cable from the shore power. Solar and wind charging should also be isolated at the same time, so you can safely inspect the electrical system without risk. 

A battery drop test will confirm if your batteries are in good health. Drop testers are available at most electrical and automotive shops and are highly effective in measuring battery life and condition. Each battery should be disconnected and tested individually, instead of collectively as a bank. 

During your battery system checks, you should also make sure all the connections to your batteries are tight, secure and can’t be moved around.  

Run the engine 

Diesel engine on sailing yacht

During the winter or long periods of disuse, its important to periodically run your engine until it reaches normal operating temperatures. Boat maintenance checks like this will keep the engine warm and the motor’s parts in good operation.

Whilst checking the engine, inspect all electrical parts contained in this area. Using a torch, look at the wiring harnesses leading up to the control panel. Also check the alternator and starter motor to confirm that all connections and terminals are clean and free from corrosion, frayed cables, or disconnections.

Lastly, check the engine for any water leaks that could damage the electrical system.   

The DC breaker panel 

Shot of electrical breaker panel

The DC breaker panel will vary from vessel to vessel. However, as part of your boat maintenance, it’s important to make sure that any thermal cut outs or switches are correctly set on the circuit board. 

If there is a fault on the circuit, the switches will automatically turn off. A single event can cause a switch trip, however if it continually cuts out this often indicates a larger problem. 

When this happens, a qualified electrician will need to be contacted to fully resolve the issue.  

Rinse your anchor windlass 

Wide shot of anchor windlass

Its best practice to always rinse your anchor windlass with fresh water to flush away saltwater residue after anchoring. Saltwater can accumulate in the area where the anchor is put down and brought back up repeatedly.

Consequently, salt can build up on the cabling and the motor below, causing it to degrade and breakdown over time.  

Electrical cabling  

wide shot of mast cables on board sailing boat

Electrical cabling coming down from the mast and going into the boat must also be well maintained.

If there are through deck cable connections at the base of the mast, then check their condition. If there are any breaks, signs of deterioration or fractures in the outer sheath that may expose the inner cabling to the elements then now is the time to get them repaired. 

Find out more 


Keep your boat in working order by discovering more handy tips with the RYA Boat Maintenance Handbook. Or brush up on your diesel engine knowledge with a one-day RYA Diesel Engine course.