Genset Exhaust Gas-Water Separator Add-on. Good Idea?

My Westerbeke 8.0 BTD currently exhausts through a lift muffler and out through the hull, above the water line. Previous boats I've owned have had much quieter lift systems. I have been staring at the space in and around the exhaust hoses and muffler and am wondering if installing a separator like Centek's, for example would be worth the time, expense and scuffed knuckles. If I could add a gen-sep to the existing system (of course making sure it would work with the machinery) would I be happy with the result? I just find that the gen exhaust should be quieter since we spend much time in the cockpit which happens to be near the exhaust port.

Has anyone had any experience with reconfiguring their generator exhaust or adding a separator? Looking for both pros and cons.

Yes, most of the gen sep units must be above the water line. I have had a peek at one of the installation manuals and I do belive I have the height required. I think any unit would help quiet the noise. Just wondering how much they help.

Well, it does seem that I should give this idea more than just fleeting consideration. Thank you for all of your advice and experience. I think I will climb on board this fall and take detailed measurements and photos. Hopefully one of the manufacturer's products will fit the bill. An 80% reduction in noise is quite remarkable.

Another interesting setup.

Thanks for the PDFs Capt Ralph. I have been reading most of the product descriptions from Centek. I do like the combo unit. It is something that I think will fit in the space a little better than both the stock lift unit AND the separator. I watched a YT vid where a Centek inline muffler PN 1400003 was placed in between the genset and the water lift unit on a gas model Westerbeke. I don't think it was designed to do that but I haven't spoken to the engineers at Centek yet. If this is something that is possible on a diesel unit (with the higher back pressure), it is something to consider as well. I think there is enough room to insert the unit. Again, not sure that this would be advisable but it would sure make the upgrade A LOT easier.

I would have thought that a set up like Boatingnut's would have some kind of impact on the genset exhaust, like back flow issues when the main was at high speed, unless its plumbed into the idle by-pass.

My old Carver 3807 dumped all water and exhaust into exhaust "boxes" molded into the hull. The boxes had holes both under and above the waterline. Only the genny had a water lift muffler prior to the box. It was very quiet as was the trickle from the AC. The mains however had that un-muffled deep roar.

I still miss that sound.

I don't have a current photo but the video at this link is a similar set up. The boat in the video is a gasser; mine is diesel.

I did get a hold the engineers at Centek. He put me onto their double chambered water lift muffler. He says it raises the water twice in two chambers and apparently it is much quieter. Before I drop $550 USD on this, I would really like to see one in action. I also have to do some careful measuring before I settle on a refit. The separator addition may or or may not fit which is why I'm looking at the double chamber unit.

BTW, the set up in this video is not recommended by buddy at Centek and probably would not be by those at Westerbeke either.

Update: I have measured the area and decided (with help from the Centek engineers) to go with the gen-sep vertical combo unit. The sound rating is on the “best” side of the scale. It will fit with millimetres to spare. The water outlet will be at or just below the LWL. It wasn’t the cheapest choice but hopefully the right one.

Rough in starts in a few weeks. I will prep the hole and thru hull fitting. Will need a seacock to hold out the water until the unit arrives in June. Evidently there’s a world-wide resin shortage. Stupid pandemic.