Preventing Electrical System Failures

Shown here are relay covers, that when properly fitted to the green seals on the actual relay connection blocks provide protection from the elements… but not when they become submerged due to improper placement in storage hatches.

There are many reasons why electrical systems fail. In our world, the primary source is the corrosive effect of saltwater. The jackplate relays in the accompanying photos are prime examples.

The electrical relays had been installed in the rearmost starboard hatch, at about mid-height on the sidewall, supported with a cable tie screwed to a bulkhead. Seawater can enter the compartment in several ways. Most obvious would be a missing or loose drain plug when the boat is in the water. The other two are less obvious.

Water can also enter the compartment through the hatch cover if not securely fastened and sealed when launching, and also when anchored stern to the sea; we see this often with hydraulic anchor systems. The most overlooked is a faulty or deteriorated boot covering the rigging tube at the deck surface. The rigging tube acts as a funnel, draining water from the deck into the compartment.

The best method to correct this is to relocate the jackplate relays under the engine cowling or the boat’s console. This requires lengthening the circuits with appropriately sized cable.

Have a safe and fun fall season!

Chris Mapp

Coastal Bend Marine | Port O’Connor, TX
coastalbendmarine.com |361-983-4841