Pickling Boat Engines

A boat on a trailer in front of a lake
  • 4-10 hours
  • Intermediate
  • 50-200

Pickling boat engines doesn't mean putting them in a jar of vinegar, it is actually the process used to salvage a boat which has been sunken, or taken on large amounts of water. Pickling is an effective way to prevent the salt water ruining your expensive boat engine. If your boat is left at the bottom of the sea for too long then the salt water will cause corrosion, this corrosion will cause your engine to break down. You need to try and get the boat out of the water as soon as you possibly can, however if you've just had a hurricane then you might want to wait until there is enough time to work on the boat.

Leaving the Boat

Although you want to raise the boat as quickly as possible, if you or someone else isn't available to work on your boat for around four hours then you should leave it under the water. As soon as you lift the boat it will be exposed to the air which will accelerate the corrosion of the engine and boat. The best way of saving the engine is to start restoring it as quickly as possible.

As soon as the boat is raised you should immediately disconnect any power sources. Take the batteries off as these will almost always need replacing. Electrolysis can cause further damage if left connected.


Get rid of all the salt water out of the engine by drenching the engine in fresh water. Don't worry about causing any damage, the aim here is to get rid of salt and mud which can dry and harden. Fresh water is also slightly better than salt water as it won't cause your engine to corrode as quickly.

After washing the alternator and starter motor can be remove because these can be used again, working quickly now will avoid wasting lots of time restoring them later. Use water to wash these out and then put them inside an oven on a warm temperature for a couple of hours until they are dry.


If you have a gas engine on your boat, take the distributor cap off and make sure you dry the whole engine. Replace the coil, condenser and points.

Diesel engines will have a drain plug which can be pulled out to let water drain out. You will need to remove the turbo if you have a turbo charged diesel engine.

Water in Engine

Take the spark plugs out of the engine and use a syringe to remove the water from each cylinder, you will have to repeat this several times for each cylinder. Then, remove the drain plug from the oil container and drain the whole tank, this must be disposed of carefully. Sometimes you wont be able to drain all of the oil and you will need to perform an oil change using a siphon hose.


Every space inside the engine must be filled with diesel or oil to prevent corrosion and get rid of any water left inside. Use a wrench to turn the engine over so that the oil coats all the parts inside your engine.