Generator Noise Level

[Todd]

I have a question about the noise level of the generators installed in Ranger Tugs.

Basically I would welcome comments comparing the noise level to the main engine. Such as it is about as loud as cursing at #### RPM.

I would especially welcome comments from R29 owners but all would be helpful.

Todd

 

[tlkenyon]

OK, you got me. How do I determine the RPM of my cursing? I imagine it is usually pretty high.... 🙂

 

[Todd]

To determin the RPM while crusing look at the engine tacometer.

 

[abcandjrc]

Everybody wants to be top banana, nobody wants to play straight man...... :lol:

 

[jroyle]

12e

 

[Nellie Too]

Hi Todd,
You might want to send a message to "Circle T" Tym, he added additional insulation to his generator compartment and it operates with little noise in the rest of the boat. I am sure he would be willing to share (I need to do this as well).
All the best,
Bob

 

[GulfSailor]

........... I would welcome comments comparing the noise level to the main engine.

It's hard to compare the noise levels because they're so different, like comparing the noise of an espresso coffee maker to that of a sewing machine.

You'll always be aware of the generator because the sound is much harsher than the engine. That's because your engine will have four or six cylinders and the generator will most likely have only one. It's 'thump, thump, thump' compared to 'purrrr'.

However, nice cool a/c makes the noise much easier to live with! 😉

 

[Shared Dream II]

I'll take a stab at the question. All points about having a different sound are valid. I would say the dB is roughly equivalent to the engine at 2000 rpm. The fan of the A/c circulation is actually louder than the genset. We have the Onan/Cummings generator installed.
Conversations are very doable inside the boat as well as in the cockpit. Away from the boat it is very quite.
When running at cruising speed for us, 3000 to 3600 rpm, you cannot tell that it is on.

 

[walldog]

At 5 to 6 AM on a cool morning in a quiet anchorage when Willie needs heat, it sounds to me like you can hear it for miles. I have asked my anchored neighbors about the noise level and most did not even notice we were running it. Yes the heat pump drowns out sound of the generator. So the sound levels will not upset the last few moments of sleep. We have the 2.7 Mase.

 

[bbrh842]

I think the generator noise leve is a HELL of a lot LOUDER than any CURSING I have EVER heard. I took the cursed thing out, threw it in a dumpster, and got a Honda 2000I.

 

[JamesTXSD]

While not generator specific, over the years I have often seen "cursing" when people meant "cruising"... yeah, sometimes they go hand-in-hand. 😉

The pitch and sound frequency make a difference: consider the sound of your diesel engine vs a leaf blower. Or a stock Harley vs a high-revving 2-stroke. Or, the whisper of your Honey's voice vs the shrill scream of a baby.

The generator is going to make some noise. What is too much to one person is soothing to another... especially when you consider that generator will allow the Keurig to get that morning cuppa going. 😀

 

[Todd]

Thanks for the replies so far. I have a Koler genset in my R29. Aftermarket installl. It produces a lower pitch noise that is quite loud in the cabin. Louder than the AC fans. Can't hear them. Quite a bit louder than the main engine when just crusin around at 1800 rpm.

I will be away from the boat for the next two weeks but when I get back I want to try to isolate the noise and see if I can reduce the overall level. I am used to generators in motor homes which are real quite. They basicly use the same units so I think the high noise level is related to the instalation. Perhaps being in an enclosed locker, or the exhast being mounted against the hull, or lack of sound insulation.

I would welcome more responces regarding the noise level of the factory installed gensets on Ranger Tugs, especialy from the R29 owners.

 

[abcandjrc]

I suspect you will find that a good part of the noise is not the exhaust or even the immediate mechanical noise of the moving parts but vibrations transmitted to the hull. It then acts like the sound-board in a musical instrument and seems to amplify the noise since it comes from multiple directions. That is the nature of gen sets (and main engines) no matter how well isolated they may be.

Added insulation will dampen some of the sound transmitted directly and will even absorb some of the vibration-induced noise, but the largest part of the problem will have to be solved by sublimation.

 

[RProffer]

To really compare sound levels, a sound level meter or decibel meter should be used. I just did a Google on them and found they can be inexpensive. Here is one for $22.00 and has good reviews.http://www.amazon.com/Mini-Digital-Sound-Level-Meter/dp/B001THX3M0/ref=pd_cp_hi_1 I found some others for less money, but the reviews were not as good. According to the reviews, the meter can be used to determine where the sound is coming from.

 

[GulfSailor]

I suspect you will find that a good part of the noise is not the exhaust or even the immediate mechanical noise of the moving parts but vibrations transmitted to the hull. It then acts like the sound-board in a musical instrument and seems to amplify the noise since it comes from multiple directions. That is the nature of gen sets (and main engines) no matter how well isolated they may be.

Added insulation will dampen some of the sound transmitted directly and will even absorb some of the vibration-induced noise, but the largest part of the problem will have to be solved by sublimation.

I fully agree that vibration and resonance could be a large part of the problem, as outlined in the above post.
In addition, assuming that you have a marine unit installed rather than an air cooled RV style one, you will have the added sound of the water being continually dumped from the exhaust, something that you would not be used to hearing in your RV.

 

[Todd]

I have a sound level meter but do not have a second boat to compare it with. Figured most people do not have sound meters so it would not do any good to ask for sound level numbers. I have asked the factory but the information is not available. They will try to get it when they have another R29 with generator hit the water. That is why I asked for a more general sound comparison, something everyone with a generator could relate to and provide.

The genset is a marine unit. I believe that the installation is part of the problem causing the hull to act as a soundboard and amplify the sound. I will be trying different configurations, such as generator hatch open or closed, placing my hand on select parts to see if the change in vibration makes a difference, and anything else I or anyone else thinks of to try to find and ultimately lower the noise level, including the addition of special sound deadening insulation products.

I cant get to the boat for a couple of weeks but keep the suggestions coming and I will let you know how I make out.

 

[Nellie Too]

Hi Guys and Gals,
This is really an interesting subject. I don't have a sound level meter but what I do is listen for the noise. If it is too loud inside the boat, I add insulation around the generator as did Tym (his insulation system is very impressive for noise suppression). If it is too noisy on the outside of the boat, I don't use it too early in the morning and ask my boating neighbors if it bothers them when I start it.
All the best,
Bob