Newbie asking for help re: $$$ install of Exhaust

[Blain]

Good morning,Newbie here, recently acquired a 1983 53’ from a friend last December. I have been reading various threads on this forum to learn as I am unfamiliar with the Hatteras vessels.Two owners back, mufflers were installed and after many years they are now rusted and need replacement. They are in the master suite under the cabinets.My mechanic gave me the option of replacing the mufflers with a straight 8” fiberglass tube instead of new mufflers. Even though no one will be sleeping when underway, I am still concerned that the noise typically reduced by the mufflers would be significant. I am told most that the noise comes from the engine room. Sourcing good mufflers with 316 SS is another challenge. And the cost is significantly different between fiberglass and new mufflers. Knowing these boats, I would appreciate your honest opinion as to what would you do in this situation. Thank you in advance,Blain

 

[Pascal]

I redid my exhaust during the repower a few years back and used fiberglass mufflers. I can’t imagine using anything but fiberglass in the exhaust system…. You should also inspect the rubber hoses as mines were collapsing.

Problem with noise without mufflers is not in the stateroom but outside the boat on the aft deck and even FB. These detroits can be real loud. I remember running a 58 with 8V92s a few times and the drone of the engines was tiring after a while

Make sure whoever does the job uses SS inserts in the fiberglass tubes/muffler so that the tee clamps don’t crush the fiberglass

 

[SKYCHENEY]

I wonder why the original fiberglass mufflers were replaced. Seems odd to ever pull those out in the first place. Maybe the owner thought those were too loud and wanted to try to reduce the noise further.

 

[Blain]

Hello,Yes, good question. I am not sure why they were replaced. My friend says the previous owner, who added the mufflers, did not find a significant difference in noise.Thanks for the tip about the SS inserts, my mechanic was going to order a 5’ fiberglass tube (8” diameter), Blue silicone exhaust hoses and T-clamps to make the connections. Both open ends are fiberglass. So just a straight tube to carry the wet exhaust out. I may have flaps installed on the openings to protect from following seas getting too deep into the system. Does that sound reasonable?BTW, I see that my first post is all clumped in one paragraph. Not the way I typed it LOL. I need to learn how to spread out the lines.Thank youBlain

 

[JD5652]

Whatever you end up doing, be careful about adding any back pressure to the exhaust system.

 

[SKYCHENEY]

The original muffler were essentially straight pipes. You could see all the way through them with just a little offset inside of them and holes with sound insulation on the sides. I'm not sure that a straight pipe would
have any more noise than the original setup.

 

[SEVEN]

Fiberglass is the only way to go.

 

[howhomes]

Check valves?]

 

[Steve Mannshardt]

Highly recommend contacting Jason at Marine Exhaust Systems in FL. I worked with Jason on replacement collectors etc for our boat. The result was nothing short of perfect.

 

[Fanfare]

I removed my original bronze "mufflers" due to electrolysis essentially leaving me with straight pipes. The noise from the fly bridge was exhausting (pun intended). At the end of a day of running on open water I was beat. On the ICW and particularly under bridges the noise was unbearable. I put in fiberglass mufflers and got a huge improvement. Still some noise on the bridge but not bad. In saloon all noise comes through from engine room not exhaust.

Fanfare has the original Jack and Jill berths which let me put the mufflers underneath the bunks on port and starboard so no problem with fit. I wondered about flapper valves for waves coming in astern but did not use. Have never had a problem. After 30 years they have held up well. No rust!

 

[dsharp]

Look at the Centek Vernatone mufflers.Fiberglass construction

 

[jim rosenthal]

Surge tubes might be useful as well, if there is room for them to be installed. Any new exhaust system should be fiberglass, and include mufflers. Centek/Vernatone have held up well for me. Clamping rings are also essential- T-bolt clamps in particular can easily crush a fiberglass tube; the clamps generate enormous clamping force.

 

[JD5652]

Surge tubes might be useful as well, if there is room for them to be installed.

While I don't know about the exhaust configuration on a 1983 53’, while my 1976 58 LRC does NOT have "surge tubes", the exhaust has a 24"+ "high spot" in it in the engine room to prevent water surge into the exhaust system and into the engine.

 

[Blain]

Thank you very much to everyone that commented. The information is critically useful to this newbie. I contacted all the mentioned avenues.. still waiting on Centek to give me a timeline & price. marine exhaust folks are working on a design but the initial designs are large for the space. But working on options.

Thank you again

Blain

 

[Blain]

Quick question on a related note. I have read the comments o. This thread about T clamps and such but what type of joining hose do you have in your exhaust system?

I see blue hose, black hose, single & double hump. I noticed blue hose goes up to 350F, black 250F.. not sure what Temps exist in mufflers. I know exhaust Temps at origin can be up to 800F. Are the hump hoses for offset joints, strength or both.

Thank you

Blain

 

[Pascal]

My exhaust are mostly fiberglass tubes running from the ERs to the stern. About 20-22’ long. Near the stern I have a 2’ section of black hose between the fiberglass tube and the fiberglass muffler. Same between the muffler and the fiberglass flange on the transom.

 

[cww]

I have a 1980's 53MY and the exhaust is pretty simple, just large fiberglass and rubber pipes straight back to the cabinets on the sides of the master, where you will find a large fiberglass muffler on each side that appears to be the vernatone brand judging from the shape. I'm used to them from diesel Chris-Crafts. They last forever, I can't imagine why someone would replace fiberglass mufflers with metal ones that have a limited lifespan. That's an odd move.

Yes vernatones are basically see-through at first glance, but that's because they use water as the sound deadening medium. The baffles are just enough to make sure water is splashing across the exhaust flow, and the design does work. My boat is not particularly loud, maybe they changed the setup by the 1980's, but you can barely hear the engines at all on the flybridge. The only place you can hear them much is on the aft deck, but it's not obnoxious. I have had older 53's as dock neighbors before and the ones from before the late-70's do seem to be a lot louder for some reason.

 

[brettportzer]

This is one of two things that I actively dislike about my 1972 43DC.

It is very loud, and essentially you drive from the aft deck.

I have 6-71Ns and I believe the naturals are louder, so maybe that is why the older ones were louder in your experience.

 

[bigbill]

it is more expensive but i used trident blue silicone hose. mainly for ease of use, it is much more flexable

 

[Blain]

Thank you all again for your comments and advice,

I am having fiberglass mufflers built by Verbatone. But there is an 6- week delay. In the meantime, I had a shop fix/weld my current mufflers so I can get on the water in the meantime. I purchased Blue silicone hoses to connect things, and I got one side installed. The port side is really a challenge due the tight opening of the Port cabinet in the master. To install, the blue hoses go on the exhaust tube that comes ER and aft on the fiberglass stump (14") that is connected to the transom exhaust exit. The problem that I am gaving is I cannot slip enough blue hose on the aft exhaust stump to be able to pull it forward over the aft end of the muffler once it's in place and have enough for clamps and the gap. Right now I can get 6" of hose pushed back, the 6" will need to bridge a 1/2" gap leaving me about 2.5" on each side for clamps. I think that's cutting it close.

Is there a way to reflect the blue hose on itself, maybe an inch or so .. If I can reflect that inch back it will give me more blue hose to work with? I have used soap and silicone spray to push the hose as far back as possible but the OD of fiberglass stump increases a bit as it gets closer to the transom. I am worried about heating the hose to allow it to be pushed more aft, as it may be impossible to pull it forward once it has cooled.

Any ideas or comments would be greatly appreciated.

Blain