A call for help was made by a fisherman around 6.30am on Thursday morning when a fire broke out in the engine of his boat, four kilometres out at sea.

Warrnambool Coast Guard deputy commander and duty skipper Keith Prest said it was lucky the vessel, carrying two people, didn't catch fire.

"He wasn't in immediate danger but if the fire got worse it would have been no time at all before the whole boat was on fire," he said.

"He tried to start the engine and not only would it not start, but smoke started coming out of it and that's when they called us. We got a crew together with a rescue boat and towed it in to the Breakwater.

"The thing is, he'd called us out a week before but they had solved the problem and got the engine started.

"There's a message in there about boat maintenance and safety. We've seen a lot of people going out without the right preparation of their boat or their knowledge of where they're going. It's scary."

Mr Prest believes the fire was ignited by loose engine wires.

"It was a fibreglass boat, and fibreglass burns really well. If it escapes out of the engine and catches fire the boat will burn right to the waterline very quickly.

"The best thing to do before going out to sea is to really check carefully. People often leave fuel in their boats all winter and then have problems with the engine.

"Make sure you check your equipment and make sure everything is current and in-date."

The rescue marks the third call-out since the start of summer for the Warrnambool Coast Guard.

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