How To Clean A Boat Bilge

Paul Luisi
by Paul

Having a dirty boat bilge can cause foul odors and a build up of oily, dirty water and sludge.

You'll find a bilge and bilge pump on types of boats like pontoons, speedboats, sailboats, yachts, catamarans and motorboats.

To clean a boat bilge, follow the steps: 

  1. Drain the bilge from dirty water, sludge and scum
  2. Scrub the bilge with warm water, a sponge and bilge cleaning product
  3. Rinse the bilge
  4. Dry the bilge with cloth or towel

Over time, the bilge can build up with large amounts of dirt so it should be cleaned regularly.

Step 1: Drain The Bilge From Dirty Water And Sludge

A bilge will usually have a drain hole for draining out water. To drain the dirty water and sludge from the bilge: 

  • Get a bucket and drain all the dirty water and sludge into it.
  • Dispose of the water appropriately and continue draining until the bilge is completely empty.

Once complete, make sure you close the drain hole. This should take approximately 10 minutes to complete.

However, it will depend on the size of the bilge and the amount of dirt to remove.

Before cleaning the bilge, drain the trapped dirty water and sludge from it.

Step 2: Scrub The Bilge With Warm Water, Soap And A Sponge

To wash out the bilge area, get bilge cleaner and pour it into the bilge.

Mix with warm water and let it soak for a few minutes. Then start scrubbing around the area.

Scrubbing the bilge with a marine cleaner will: 

  • Loosen sludge, grime, oil and grease:  The marine cleaner will help loosen the trickier dirt that's harder to dissolve and remove.
  • Remove the foul odor: The bilge cleaner will remove the foul odor from dirty water and sludge that builds up over time.
  • Not damage the bilge: Marine grade bilge cleaners will not damage fiberglass, hoses, wiring or plastic like stronger cleaners would.

This step should take approximately 10 - 15 minutes to complete.

Scrub and wash out the bilge with a marine grade cleaner to remove dirt, oil, sludge, scum and grease.

Step 3: Rinse Bilge And Drain It Out Again

Once the bilge area has been scrubbed thoroughly and the dirt has been dislodged: 

  • Rinse it with warm water: This will remove the cleaning fluid and the tough stains and spots that need extra attention.
  • Drain it out again: Drain all the dirty cleaning water through the drain hole into a bucket

This step should take 5 minutes at most.

Rinse out the bilge with some warm water and drain it out into a bucket.

Step 4: Dry Out Bilge With Cloth or Towel

Dry out the bilge with a towel or cloth. This will remove any remaining cleaning fluids, stains or dirt.

Once this step is complete, the bilge should be spotless, free from foul odors and sludge.

Use an old towel or cloth to dry out the bilge after washing it.

Alternative Bilge Cleaning Options

There are other ways to clean the bilge including: 

  • Hire a bilge cleaning company: This service will do all the cleaning work. This will cost $150 on average.
  • Hire a professional individual: Hire a person from craigslist or from a local marina to do the cleaning.

This options are best for those that want to outsource the cleaning work.

Hiring a commercial bilge cleaning service means cleaning should run smoothly and saves the hassle of doing it yourself.

Ongoing Bilge Cleaning Maintenance

Cleaning out the bilge should be done at least once a month.

This will help prevent rotten odors and dirt building up.

Use a scented bilge cleaner and a bilge cleaner degreaser regularly to keep the area fresh, clean and smelling great.

Clean the bilge at least once a month as part of ongoing cleaning maintenance. This will prevent a build up of dirt or damage to the bilge.

Products To Avoid When Cleaning Bilge

When cleaning out the bilge, you should avoid: 

  • Using a pressure washer: This can damage the material and spray toxic oils and grease everywhere
  • Using household cleaners: These cleaners are not marine grade and tend to not be biodegradable.
  • Using bleach regularly: This can harm the bilge material and pollute the water if it leaks out into sea.
Avoid damage or pollution when cleaning the bilge by not using a pressure washer or household cleaners. Use marine grade cleaners only.

How To Clean Boat Bilge Video Instructions

Below is a video from zoffinger on cleaning out a dirty bilge and the techniques to have it looking spotless.