Handy Tips on How To Quiet Your Boat

A constantly vibrating boat can lead to loose bolts and introduce minor damages to various parts of the boat. As a result, it becomes crucial to resolving the vibrating boat issue. But how do you do it?

The quickest methods for making a boat quiet include installing soundproofing and or sound dampening materials into the boat’s cowling. Materials including rubber (self-adhesive or non-adhesive) and anti-vibration membrane in addition to aluminum layer are highly advisable.

This article covers essential yet practical tips to quiet your boat, along with some FAQs related to the topic. Please follow the article until the end.

How Do You Reduce Outboard and Inboard Noise?

Any loose bolts, nuts, and or rivets are the significant reasons behind a noisy boat. Parts can become loose with time, so check for any such loose bolts, nuts, or screws and tighten them.

Excessive friction increases the motor’s noise by extreme levels. Consider lubricating the engine for smooth and much quieter operation. There exist a marine engine lubrication system that aims to reduce friction in marine engines.

If the noise still exists, it probably requires another fix discussed below.

Noise Reduction on Outboard Motor To Quiet Your Boat

The cowling is the outboard engine’s cover shipped with the engine that barely aids noise reduction. Therefore, it’s advisable to install another layer of heatproof and waterproof cowling over the current cover. Avoid removing the original cowling since the removal process can leave damage to the engine.
A DIY muffler made of PVC acts as a silencer for an outboard motor.

Noise Reduction on Inboard Motor

Installation of rubber mats within the motor area acting as insulation is the best way to reduce noise on an inboard motorboat. Ensure not to block air vents causing an overheated boat.
Use noise control barrier material that can absorb the vibrations leading to a quieter boat. A barrier of 32″x54′ with a 1″ thickness will cost AU$155+. These barriers are self-adhesive, so peel and stick to the surface.

How Effective Is Soundproofing On A Boat?

It’s impossible to deflect all the noise generated in a boat. Still, many people get curious about how effective it will be to install some soundproofing on their ship. Here’s the answer.

A boater can expect to eliminate up to 60%-70% of sound generated in the boat; if you quiet your boat properly. Soundproofing panels cannot block the noise entirely but can dampen the low-frequency sound waves with long wavelengths.

Installing multiple soundproofing panels will be effective, but it’s useless to install several layers on a given surface. Moreover, the quality of panels governs the amount of noise blocked.

Using thick and high-density foam sheets will deflect most of the noise, whereas soft and low-density pads will allow most noise to pass through them.

How to Make an Aluminum Boat Quieter

Please follow this guide to make your aluminum boat quitter step-by-step.

Required Items

Styrofoam
Non-expandable foam filling
A carpet

Procedure

Ensure tightening of any loose bolts, nuts, screws, and rivets. Fix the leaks in the boat (if any). Finally, make sure that the structure of the boat has no damages before proceeding.
Fill the gaps in between the hull and floor braces with the non-expanding foam. Please note that the use of expanding foam in an aluminum Jon boat will rip off the rivets.
Take the measurements of your boat’s floor’s structure and cut the Styrofoam accordingly. Tack the sheet to the floor with caulk. Remember to leave some space for the drainage plug.
Please note that most people skip this step, assuming it not so important, which is false.
Just like you installed the Styrofoam, install the carpet above the Styrofoam sheet. Cut the carpet slightly longer (1-3 inches) so that the ends can extend up the wall.
There are some outdoor carpets washable with a water hose. Try using them for the best results (since they’re water-friendly).

Tips

Better the Styrofoam, carpet, and foam sticks to the floor, better the results.
Use self-adhesive sheets (if possible) as they’ll stick perfectly.
Avoid using nails or sharp objects to tack the sheets.
If you’re looking to painting your boat, do so after installing the soundproofing sheets.

Why Do You need To Quiet Your Boat?

Even if you’re fine with the annoying noise produced by your boat, here are a few reasons to quiet it:

For the sake of compliant sailing, you’re required to limit your boat’s noise. In Alabama, noise shouldn’t exceed 86dB when measured 50 feet away from the ship. In New Mexico, you’ll have to ensure not to let others generate a complaint due to your noisy boat.
Soundproofing helps keep the engines cooler during high temperatures.
A fishing boat must be soundproofed, or else the fish would swim away to another end of the water body.

Tips For Effective Soundproofing

Create proper templates before cutting the soundproofing sheets. Take appropriate measurements from every possible side and draw a rough design on paper for better understanding.
Always leave enough space for ventilation.
Do not use soundproofing materials that aren’t waterproof, or else you won’t get enough soundproofing.
Ensure a gap of six inches between the soundproofing sheet(s) and exhaust manifolds.
Cut the sheets with sharp tools for precise and accurate cutting. It also ensures the edges don’t get torn or damaged.
Use high-quality adhesive tape for sealing the edges.
There should be no gap or cavity between the soundproofing sheets.

Effective Sound-blocking Barriers For Boats

Please note that the boat market is filled with thousands of varieties of soundproofing sheets. Below are a few of them:

Fiberglass Composite: They’re highly flexible barriers ideal for cabin’s ceiling and walls. Use them on noisy pipes for insulation.

Mass load Vinyl: These rigid barriers are made of sand, silt, and fine metal particles that all together absorb the noise and vibration. Install them on your ceiling and or walls for effective noise cancellation.

Temporary Vinyl Barriers: These barriers fit perfectly on the floor, line hulls, line engine compartments, or cover hatches that offer a peaceful sleep on the boat. As the name suggests, they’re not suited in the long run.

Soundproofing Coating: You can apply a coating of soundproofing liquid that’s capable of absorbing sound and converting it into low-grade heat. These coatings are non-toxic, water-based, resistant to corrosion, and applied to hulls, hatch covers, and engine compartments.

Vibra Block: This sound dampening sheet is industrial-grade that says a lot about its quality. Their primary use revolves around steel hatch covers, compartments, and pump closure.

It’s a lightweight product that doesn’t ruin your boat’s appearance.

Acoustic Foam Panels: Such panels can absorb and deflect sound vibrations. These panels are resistant to moisture and hence can be washed several times. Installation areas include walls, ceilings, and floors.

Echo Absorber Acoustic Panels: Echo absorber panels are majorly made of recycled cotton and are quite popular due to their low cost. Unfortunately, these panels are mountable only on flat surfaces.

Frequently Asked Questions (FAQs)

Is a 2-stroke outboard motor quieter than a 4-stroke outboard motor?

Most 4-stoke outboard engines are much quieter than any 2-stroke outboard motor, whether idle or running. The noise levels of different 4-stroke outboard engines do differ based on the manufacturer.

Why are 2-stroke engines so loud?

Any 2-stroke engine would fire two times more than a 4-stroke engine. Additionally, 2-stroke engines lack valves to intake and exhaust, leading to increased noise.

What Areas Can Be Soundproofed?

Not only floor, but you can also install overhead barriers and install soundproofing sheets on the walls in a cabin.

Conclusion

Manual installation of soundproofing materials on a boat can be tiresome, but that’s the only way to achieve the goal.

Avoid blocking air vents and make sure the material doesn’t touch any moving parts.

Also, try your best to keep the soundproofing materials out of direct contact with the extremely hot boat parts, as that can start a fire.