How To Clean A Dirty Boat

Paul Stockdale Author Avatar
Written by Paul Stockdale | December 2, 2023

Giving a dirty boat a thorough cleaning can be done with some hard scrubbing and simple washing.

To get started, you'll need a power washer, boat soap, hot water, bilge cleaner and other marine cleaners to tackle that stubborn, hard-to-remove dirt.

Power washing a boat with warm water will also help with the grimiest dirt and remove sea salt and scum lines.

To clean a boat:

  1. Deeply clean & polish the exterior surfaces: Power wash and scrub dirt from the exterior surfaces. Use a power washer on the exterior surfaces to remove excess dirt. Scrub the exterior surfaces with a bristle brush including the hull, gel coat surfaces, deck, canvas and engine area. Dry the exterior surfaces with a cloth and apply boat polish to protect the surface from UV damage
  2. Thoroughly clean, wipe down & vacuum interior surfaces: Use a cloth and marine soap to wipe down interior surfaces including cabinets, cockpit, heads, bilge and galley areas. Vacuum marine carpets and boat seats to remove dust and dirt from them

These boat detailing tips and procedures apply to all boat types including bowriders, pontoons, center consoles, yachts, sailboats, catamarans, cabin cruisers, houseboats, speedboats and motorboats.

A clean boat helps with overall boat maintenance, ensures your boat runs smoothly, preserves the life of the materials onboard and improves boat performance and functionality.

1. Deeply Clean & Polish The Exterior Surfaces

Cleaning boat exterior

The first step in cleaning a boat is to clean the boat's exterior surfaces.

Items to clean when cleaning the exterior of a boat include:

  • Boat hull and gel coat surfaces
  • Boat canvas
  • Boat deck area
  • Boat engine
  • Exterior aluminum and fiberglass parts

Cleaning The Boat Hull

Washing and cleaning the dirty boat hull can be done in two ways, cleaning the hull in the water or cleaning the hull outside of the water

The easiest way to clean the hull is when the boat is out of the water.

To clean the hull of a boat, you will need boat hull cleaning products like marine soaps, microfiber cloths, a rotary brush, a pressure washer and a scrubbing brush.

The boat hull should be cleaned every 1 to 3 months.

Cleaning The Hull When The Boat Is Out Of The Water

To clean a boat hull when the boat is out of the water, simply follow the steps:

  1. High-Pressure Rinse: Use the power washer to perform a high-pressure rinse of the hull. This will help remove any bulky and heavy dirt.
  2. Scrub The Hull With Soap & Hull Cleaner: Use a brush to scrub those tougher areas with soap and marine hull cleaner products. (Be careful not to remove paint)
  3. Power Wash The Hull With Warm Water: Once you've scrubbed the entire hull, use the power washer with warm water to blast away all the dirty spots.
  4. Dry The Hull With Marine Cloth/Towel: Use a cloth or towel to dry the hull and remove the final bits of dirt and scum lines.

Once you follow the steps, the hull will be spotless and ready to go.

Cleaning The Hull When The Boat Is In The Water

You'll need underwater cleaning tools like a hull scraper or a rotary brush to help wash and clean the hull.

You'll also need marine-grade environmentally friendly cleaning liquid.

To clean the hull when the boat is still in the water:

  1. Use Rotary Brush To Remove Heavy Dirt: Use this to scrub the hull and remove dirt. This will help with trapped dirt and can be done from the dock.
  2. Remove remaining dirt with scrub: Use a scrub to manually scrub the hull from the water. Use marine grade and environmentally friendly cleaning products for this.

These two steps will help tackle any dirt and mildew build-up in and around the hull area.

Read cleaning a boat hull in the water guide for more methods of getting rid of dirt on the hull in the water.

Boat Hull Cleaning Time
Cleaning a boat hull when the boat is out of the water should take approximately 30 minutes to complete depending on the size. Cleaning a boat hull in the water should take approximately 45 minutes to 1 hour depending on the size.

Cleaning The Boat Canvas

When cleaning a boat canvas, you will need a boat canvas soap, a soft bristle brush and a hose. Do not use a pressure washer on the boat canvas.

Some smaller boat canvases can be machine washed (under 110 degrees).

To clean a boat canvas:

  • Gently scrub the canvas with canvas cleaner: Use a soft bristle brush and gently scrub the boat canvas with water and a canvas cleaner
  • Rinse the dirty water off the canvas: Use a hose to rinse the dirty soap off the canvas
  • Wipe the canvas with a towel: After hosing it, use a towel to wipe off any final pieces of dirt or stains on the canvas and let it dry out in the sun

Check the manufacturer of your specific boat canvas as they may have specific do and don'ts when cleaning the canvas area.

Some manufacturers recommend using a mix of baking soda and soap to help remove really tricky stains and dirt from the canvas surface.

The boat canvas will need to be cleaned once per month.

Boat Canvas Cleaning Time
Cleaning a boat canvas takes approximately 20 to 30 minutes to complete.

Cleaning The Boat Deck

When cleaning a boat deck, you'll need boat deck cleaning products like a scrub, warm water, soap and deck cleaner.

Deck cleaner will help protect from future stains.

To clean a boat deck:

  1. Scrub the deck with soap: Simply get some hot water and soap and start scrubbing off the tougher and harder to clean dirt on the deck
  2. Scrub the deck with deck cleaner: Wet the deck with warm water again. Apply the deck cleaner to the the surface. Use a deck brush to wash out grime and protect from future stains
  3. Dry the deck with a marine cloth/towel: Use a cloth or towel to dry the deck

Once you've followed the steps, the boat's deck should be clean and spotless.

It'll also have a protective coating to help prevent future stains.

Boat decks are can be made of different surfaces from teak to non-skid.

Teak deck cleaning and non-skid deck cleaning typically require different cleaning products when washing them but the process of washing remains the same.

A boat deck should be cleaned once every month.

Boat Deck Cleaning Time
Cleaning a boat deck takes approximately 15 to 30 minutes to complete. This will vary based on deck material, the size of the deck and the condition of the deck.

Cleaning The Boat Engine

These boat cleaning instructions apply to outboard motors. You'll need soap, warm water and boat salt remover cleaner.

To clean the boat engine:

  1. Seal fuel and oil containers: Make sure the fuel and oil containers are closed so no water gets into them.
  2. Apply warm water and soap: Use warm water and soap to brush and scrub the dirty areas around the engine.
  3. Apply boat de salt cleaner: Use a boat de salt cleaner to help remove sea salt from the engine and engine bay.
  4. Dry with a cloth: Dry the engine off when finished washing to remove those stubborn stains and build-up of dirt.

Once you follow the steps, the engine should be clean and protected from corrosive sea salt.

If you plan on cleaning the engine in more detail, read how to clean a boat fuel tank for information on how to do it safely.

Boat Motor Cleaning Time
Cleaning a boat engine should take approximately 15 to 25 minutes to complete.

Cleaning Aluminum & Fiberglass Parts

When cleaning aluminum and fiberglass parts, you'll need aluminum and fiberglass cleaning products, a pressure washer, a scrub brush and a drying towel.

To clean the aluminum and fiberglass surfaces on the exterior boat surfaces:

  • Scrub the dirty exterior aluminum and fiberglass surfaces with a cloth or brush: Use a brush or cloth and scrub the aluminum cleaner or fiberglass cleaner soap and scrub the dirty aluminum and fiberglass surfaces
  • Use a power washer to blast away the dirt: After scrubbing, use a power washer to blast away dirt and dirty grimy water
  • Use a towel to dry the aluminum & fiberglass surfaces: Use a clean towel to dry away the excess water and dirt. This will help add a shine and remove any remaining stains or dirt

The extra aluminum and fiberglass parts on a boat should be cleaned every 1 to 3 months.

Fiberglass & Aluminum Parts Cleaning Time
Cleaning the aluminum and fiberglass parts should take approximately 10 to 15 minutes to complete.

2. Clean, Wipe Down & Vacuum Interior Surfaces

Cleaning boat interior

The next step when is to clean the interior of the boat.

Items to clean when cleaning the interior of a boat include:

  • Boat seats
  • Engine
  • Bilge
  • Marine carpet

Boat seats should be cleaned once a month to keep them clean.

Cleaning The Boat Seats

To clean the boat seats, you'll need a vacuum, warm water, a scrub or brush, marine vinyl cleaner, soap and a cloth.

The steps for cleaning the boat seats:

  1. Vacuum the hard to get surfaces: Use a vacuum to get the dirt in the tricky spots.
  2. Pour warm water and soap over the seats: Use warm water and soap to brush and scrub the dirty areas.
  3. Dry seats with microfiber cloth: Use a microfiber cloth to dry the seats and remove mold, dirt or stains.
  4. Spray seats with UV protective spray: Use a UV protective spray to help with sun damage and prevent seat cracking.

The boat seats will look new once you remove mold and dirt.

Read the how to clean boat seats guide for more methods on thoroughly cleaning your seats.

Boat Seat Cleaning Time
Cleaning boat seats takes approximately 15 - 20 minutes to complete.

Cleaning The Boat Bilge

To clean the boat bilge, you'll need warm water, a cleaning brush, bilge cleaner and a towel or cloth.

The steps for cleaning the bilge:

  1. Put soap in the bilge with warm water: Mix soup with warm water in the bilge.
  2. Scrub the dirty areas with a cloth: Use a cloth to scrub the dirty areas.
  3. Pump out the dirty water: Pump out the water in a safe and legally compliant way.
  4. Pour water into bilge with bilge cleaner: Mix water with the bilge cleaner and let it sit for at least one hour.
  5. Drain the bilge: Drain the bilge of all fluids and dry it off with a cloth.

Once followed, the boat bilge will be free of dirt, stains, mold or any bad smells.

Read how to clean a boat bilge for more methods on washing the bilge.

Boat Bilge Cleaning Time
Cleaning a boat bilge takes approximately 20 minutes to complete.

Products To Use When Cleaning Boat

The products needed to clean a boat are:

  • Pressure Washer: A pressure washer is needed to blast away the exterior dirt on the hull and deck area. This will help clean the boat, remove scum lines and any staining
  • Bilge Cleaner: Bilge cleaner will help clean the bilge area, remove grime and trapped dirt and it will also remove any foul odors caused by a dirty bilge
  • Hull Cleaner: A top boat hull cleaner will help remove scum lines, stains on the hull, dirt and barnacles from the hull surfaces
  • Boat Seat Cleaner: Depending on the type of boat seat material, you will need a seat cleaning product to match your own boat seat material. This could be a marine vinyl cleaner, leather seat cleaner etc.
  • Deck Cleaner: Deck cleaner is needed to remove stains, dirt and grease from the deck. This could be a teak deck cleaner, non-skid fiberglass deck cleaner etc.
  • Marine Carpet Cleaner: A marine carpet cleaner is used to remove stains and dirt from the interior marine carpets and help to clean it
  • Boat Polish: A top boat polish or wax is used to add a protective coating to the exterior of the vessel and it also add a shine
  • Boat Polisher: A top boat polisher is used to polish any cleaned surfaces
  • Boat Engine Cleaner/Degreaser: An engine cleaner or degreaser can help remove trapped dirt and grease in the engine bay area. This can be important to clean for the overall health of the boat's motor
  • Marine Carpet Cleaner: A top marine carpet cleaner helps clean and remove dirt from boat carpets

These products are enough to completely clean the boat interior and exterior.

Our list of the best boat cleaning products will also assist with cleaning the boat.

Frequently Asked Questions

Below are frequently asked questions about boat cleaning.

What Are The Boat Cleaning Benefits

The boat cleaning benefits are below.

  • Improves Boat Aesthetics: Regularly cleaning a boat will improve the overall aesthetics of the vessel and have it look like a new boat
  • Protects Boat Paint: Cleaning a boat will help protect the paint against damage, staining and corrosion
  • Improves Boat Performance: Boat cleaning will remove heavy dirt and help the boat move better through the water
  • Protects Against Boat Damage: Heavy and extreme levels of dirt damage the boat. Regularly cleaning it helps protect the boat against damage caused by extreme dirt
  • Saves Money On Boat Parts: Regularly cleaning a boat means money is saved on boat parts as the parts will not need to be replaced as much
  • Retains Boat Value: Regularly cleaning boats ensures the boat is kept in good condition with limited wear and this helps with the overall value of the boat

How Often Should A Boat Be Cleaned?

A boat should be cleaned once every 3 months.

How Long Does It Take To Clean A Boat?

A boat cleaning session takes between 1 and 3 hours. However this will vary based on the size and condition of the vessel.