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Dry stacking genny.....

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oscarvan

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Or a different wet exhaust system. Genny is LOUD. Not inisde the boat, it's in a sound box, but outside. The exhaust and water noise is substantial enough where I would not be comfortable running it all night in an anchorage with other people close(ish) by.

Exhaust goes into a simple standard black non metallic water lift, loops up and out.

Ideas?
 
What part of the exhaust is loud? The water splashing out or the exhaust note itself

My 53 makes a pretty loud splash / spray noise as it shoots out under some pressure. We never anchor close about to others for this to be a nuisance and from about 100’ away you can barely hear it. Two options. First install a water separator that will drain the water separately eliminating the pressure. Second, would be to increase the hose and thru hull size so that water does not come out with so much pressure

Now if the noise isn’t the water but the exhaust note, that would be due to lack of raw water flow. My 53 has a shower head style intake, not sure if that s what you have on yours. Problem is that the hole can get clogged either by paint (careless yard worker) or by growth.

I just went thru this in the last few days with the Ohnos 45 on the 116 I run. We ve been in the Exumas for 3 weeks and both gens were a bit loud. Check the thru hulls and a number of holes were clogged by shells reducing flow by about 30%. They ran cool, right on 180 F but loud

Also for some reason these are sea grass magnets. After a day, enough grass has been sucked tight against the inlet that flow gets restricted. Turning off the gen release the suction so I ve switching genny every day.
 
Make sure the drop tube in the Aqualift is not broken off. Or has a hole in it
 
Water AND exhaust are loud. System is in good state of repair. I'll have to shoot some video next time I run it. I'll have to do some distance noise readings too.....
 
For the exhaust sound, Check the thru hull outside the boat to eliminate that. I assume you checked the impeller, how old is the pump body? Any wear? Check the heat exchanger inlet as well for debris. You have to start with the basics

After my first reply, I noticed the port gen was louder with less water flow and some puffs of steam. Sent a crew down, has soon as he pulled the sea grass off the thru hull the noise changed, more water came out and the steam went away
 
A Gen-Sep would help. Google it.
 
I’m not a very good artist but I have done this to the last three boats that I own. The exhaust out of the muffler goes straight up about 6 or 7 inches to a T. At the T you’ll go straight out to the haul to a through haul. At the top of the T you add another pipe about six or 7 inches higher up and then put a elbow at the top headed to the hull and an upper through hull. The water being heavier will flow out of the bottom and the gases will go to the top and exit through the upper through hall. You will have virtually no sound coming out of the side of the boat other than a slight roar from the generator which is normal. It’s a very cheap way to get rid of the noise completely on the side of the boat. I’ve even done this when the water and gases exit all the way to the stern. I would go out the side of the boat with the gases and let the water trickle out the back.
 

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Sorry the photo came in sideways I was unaware that it was going to do that. The exit is the hull.
 
While I agree that I don't like noise bothering me I also appreciate being able to hear the exhaust to know when I have an issue. Wife still can't understand how I am able to figure out waterflow issue before it's a problem. I hear the change in tone, look at discharge and see a bit of steam. Shut down for a quick strainer clean also releases grass sucked up against clamshell.

Sound I hate but learned to tune out until it was time to appreciate it.
 
I found a solution to that in the form of a clamshell fitting over the generator discharge. It doesn’t appreciably reduce water flow or cause a backup, but it muffles the splashing and engine noise you would otherwise hear standing next to it. It was a few dollars.
 
Here’s what I was talking about with the clamshell over the exhaust. It eliminates all of the generator engine noise all you hear now is water whooshing and even that’s much quieter than it was.https://youtu.be/F6z1uLj0h2E
 
Here’s what I was talking about with the clamshell over the exhaust. It eliminates all of the generator engine noise all you hear now is water whooshing and even that’s much quieter than it was.https://youtu.be/F6z1uLj0h2E

I like that a lot...... And it is the least inva$ive thing to try first. I'm planning a 1 week haul this spring/early summer for a coat of paint and a gear checkup. Sounds like the perfect time to put that on.
 
Here’s what I was talking about with the clamshell over the exhaust. It eliminates all of the generator engine noise all you hear now is water whooshing and even that’s much quieter than it was.https://youtu.be/F6z1uLj0h2E

Yes, that is nice. I still think a gas sep is much quieter.
 
Yes, that is nice. I still think a gas sep is much quieter.

Now this is anecdotal (borderline heaarsay) and not proper science (correlation and causation not being the same thing and all that) but I have a friend, doctor, who had bought a boat with an ol' Perkins in there. Chooched right skookum until you got to about 65% power and then she'd get a hot flash straight line all the way to the buzzer (after we reconnected it, someone had sabotaged the jeezeless thing).

Wise men were consulted, judges bought, incense burned and diesel mechanics paid their ransom fees....... To no avail. A half a catalog of parts and pieces later she still purred like a kitten until you wanted to trot or gallop and then MEEEEHHHHH!

Until my buddy said..... "I want to SEE what's going on." You see..... she had one them separators on there...... and all you got was a dry oooohhhhhmmmmm until the MEEEEEHHHHHHHHH! of course. He wanted to see his water flow standing on the fan tail while an able bodied assistant worked the boiler.

So he yankered the darn thing out, went "direct" and we tried again. And she purred like a kittien and growled like a lion doing all of 8.6 knots..... Did I mention this being a Hardin Voyager? Genius design, but she sure pushed a lot of water. Of course I'm one to talk with twenty something tons of two stroke rotten dinosaur belching Motown....... but I digress. Anywhom..... she kept her cool and her flow was, how you say at home cheri? "Une piece the resistance".

Point being..... is my Genny going to like that.........I mean, being pretty much in a fast trot nay slow gallop 24/7.......

I yield the rest of my time to the gentleman......
 
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Now this is anecdotal (borderline heaarsay) and not proper science (correlation and causation not being the same thing and all that) but I have a friend, doctor, who had bought a boat with an ol' Perkins in there. Chooched right skookum until you got to about 65% power and then she'd get a hot flash straight line all the way to the buzzer (after we reconnected it, someone had sabotaged the jeezeless thing).

Wise men were consulted, judges bought, incense burned and diesel mechanics paid their ransom fees....... To no avail. A half a catalog of parts and pieces later she still purred like a kitten until you wanted to trot or gallop and then MEEEEHHHHH!

Until my buddy said..... "I want to SEE what's going on." You see..... she had one them separators on there...... and all you got was a dry oooohhhhhmmmmm until the MEEEEEHHHHHHHHH! of course. He wanted to see his water flow standing on the fan tail while an able bodied assistant worked the boiler.

So he yankered the darn thing out, went "direct" and we tried again. And she purred like a kittien and growled like a lion doing all of 8.6 knots..... Did I mention this being a Hardin Voyager? Genius design, but she sure pushed a lot of water. Of course I'm one to talk with twenty something tons of two stroke rotten dinosaur belching Motown....... but I digress. Anywhom..... she kept her cool and her flow was, how you say at home cheri? "Une piece the resistance".

Point being..... is my Genny going to like that.........I mean, being pretty much in a fast trot nay slow gallop 24/7.......

I yield the rest of my time to the gentleman......
I think your story states, Had a gas-sep, had problems, removed it and all was well.
My response,, Bunk.
I've installed to many of the CenTek products. Never an issue. On my installs the water discharge is rite at or slightly below the boot. So you can see a hint of water pouring out. The dry exhaust a few inches above or the original outlet.
I recall a 70 something Hatt where the generators Gas-seps water discharge was over 10" below the water line. No issues there either.
 
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Roger. Bunk. I will have to check required flow rates for genny and match to separator. First I'm gonna try the clam shell. I'll have to get video of the thing.
 
Roger. Bunk. I will have to check required flow rates for genny and match to separator. First I'm gonna try the clam shell. I'll have to get video of the thing.
From the mfg, the size of the gen-sets exhaust matches the gas set hose size. Not much science to it.
The CenTek kids are great on the phone also.
I don't work for them or really trying to push their product.
Ive just been here a few times.
 

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