420/44 DB Owners Club

Carpediem44DB said:
I mostly cruised at hull speed as we were never in a hurry to get anywhere but it seems that when we were pressed for time, the 44 liked 2200 Rpm which gave me about 20 Kts at about 36 gallons an hour or about .4 MPG.
Carpe Diem
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I think yo
Carpediem44DB said:
I mostly cruised at hull speed as we were never in a hurry to get anywhere but it seems that when we were pressed for time, the 44 liked 2200 Rpm which gave me about 20 Kts at about 36 gallons an hour or about .4 MPG.
Carpe Diem
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If you convert 20kts to MPH for MPG you get 0.6 MPG which is closer to what I got when running at cruise. I ran a little harder at 2250-2300 and ran 25-26 MPH with a fuel burn of 0.7 MPG. If I pushed it to 2400 the boat would run 28 MPH.
 
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I purchased my 44 DB sept 2020 with no generator. It ingested sea water and was removed .I have purchased the new generator but have not installed it yet. I will also look into the check valve as I don’t have one in my exhaust now.This post could not have come at a better time for me.thanks
 
Alex F said:
Dean,
When fully loaded, my genny exhaust is just about at the waterline. When underway (regardless whether on plane or trolling at 9kts), the stern sits lower, so the genny exhaust is pretty much submersed underwater.

Are you saying that you have this type of inline check-valve installed?

View attachment 96831

I definitely don't have it and never heard/seen it being used on any SRs to solve a problem you describe. If this would be a common issue, even a specific model related, we'd hear much more about it over the years.

The only difference in my setup is that I upgraded my muffler from stock 6" to a 10". The reason was to reduce exhaust noise.

If the story you got is related to the water getting in the cylinders, it most likely was caused by raw water intake. A simple scenario is attempting to fire up generator while underway (especially on plane). If it doesn't fire up within one or two attempts, now you're risking water injection being forced in. Years ago, a friend "killed" his generator during FW flushing by constantly supplying water while genny wasn't starting. With city water being constantly turned on, cranking and stopping several times forced the water into the cylinders causing a hydrolock.

Having said that, just b/c they installed an exhaust check-valve on your boat, it doesn't necessarily mean that generator failure was caused by exhaust letting water back into the engine. At least that's my preliminary conclusion until I hear more details supporting the theory of the story you were told.



For some reason I can't find a link to where I ordered it, but the stock model is 5415, Mayfair Marine remote mount blower 112 C.F.M. 12VDC 5.5amp
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Hi Alex,
Are you satisfied with the 10” muffler to reduce genny noise? Ours too is louder than we would like!
Model #?, pictures?
Thanks, Steve
 
Pura Vida dos said:
Hi Alex,
Are you satisfied with the 10” muffler to reduce genny noise? Ours too is louder than we would like!
Model #?, pictures?
Thanks, Steve
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Purchased a similar muffler and am very happy with the sound dampening results. The water is really all you hear at anchor. Forgot where I purchased it but will try to search.
 
cod said:
Alex,

Many years ago we took a trip to Nantucket. I had my genny running. A friend of mine with a 40’ dancer was not running his generator while cruising. We were going from Montauk to Nantucket and there were rolling swells. The best we could surmise, water must have backed up the exhaust and into the cylinders with pressure from the swells causing the genny exhaust to be submerged. Luckily we were able to pull the plugs and blow it out and get it started. Ever since then, I always run my genny when cruising unless I know I will only be going slow.
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Hey Steve,
What you described is very interesting and puzzling experience. Please correct me if I'm wrong, so far, what I understand is that your conclusion on the cause of the flooded cylinders was based on two facts, not running generator and rough/rolling seas. Since you mentioned plugs, it sounds like your friend's 40DA was a gas boat.

If the situation you experienced with your friend's generator was really caused by only two variable you mentioned, I would imagine that every boating forum would be flooded with complaints from puzzled boat owners. For that reason, I believe that there has to be more to cause the water entering the cylinders.

When I had my 320, I put very little hours on the genny and 90% of those hours were on the hook to run A/C or cook a meal. The boat had seen rough water and the genny always fired up on the second crank.

If I'll say that my Inspiration did thousands of miles with genny off, it'll be an understatement. She's has seen every possible seas conditions. So, I'd like to believe that the fact that water hasn't entered the generator's block was not based on pure luck, rather on the proper design.

Tom mentioned two components in the installation. BTW Tom, in my case, just like shown in your pictures, my boat has the large loop of the exhaust hose coming from the muffler and anti-siphon vacuum breaker. In addition, the 3rd component is the mushroom shaped thru-hull (not the SCOOP type). Boats that use scoop type thru-hull are at risk of water being forced into the block by applying too much pressure, which overpowers the impeller.

I guess, it's worth mentioning that in my case, I have the 4th component, which is the larger muffler. I'd like to believe that it adds a benefit of a volume. Meaning, that it would take much more constant pressure of sea water to continuously enter the system. Comparing to the original muffler size, in my case it would require additional ~40% of water to fill the muffler.

What's most puzzling about the topic is the fact that we're looking at the same models, only 1 year apart, having different configuration. However, since Dean's generator was replaced, I think the check-valve was an aftermarket add-on.

Having said that, it would be interesting to hear if any other 420/44DB owners have the exhaust check-valve installed.
 
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Pura Vida dos said:
Hi Alex,
Are you satisfied with the 10” muffler to reduce genny noise? Ours too is louder than we would like!
Model #?, pictures?
Thanks, Steve
Click to expand...

Steve,
Yes, I'm satisfied with the muffler upgrade. It doesn't do a magic of making the exhaust silent, but I'd say it cuts down good 30% of the noise. For couple hundred bucks it was no brainer. I got Centek 1500027, 2"x2" Vernalift 10" x 10".

A word of caution, it's a very tight fit. I had to shim one side to ensure adequate clearance from the STBD engine's exhaust.
 
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Alex F said:
Steve,
Yes, I'm satisfied with the muffler upgrade. It doesn't do a magic of making the exhaust silent, but I'd say it cuts down good 30% of the noise. For couple hundred bucks it was no brainer. I got Centek 1500027, 2"x2" Vernalift 10" x 10".

A word of caution, it's a very tight fit. I had to shim one side to ensure adequate clearance from the STBD engine's exhaust.
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Alex it sounds crazy but I think my combination of the larger muffler and the check valve greatly reduces the sound on the exterior of the boat. Initially, before I added the larger muffler I thought the check valve was a muffler and it was pretty quiet as it was.
 
Islandtime04 said:
New topic: I need to replace my sliding screen door. Has there been any discussion on the best way of doing that? I've studied the problem, but aside from unscrewing everything I see I'm not sure how to approach it. Has anyone done that before? Thx
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This was also discussed in this thread: http://www.clubsearay.com/index.php?threads/44-2008-sb-screen-door.44908/
I can confirm that you need to get both glass doors off to get the screen off. On my '06 the only way I could figure out how to remove the stationary glass door was to cut a small notch with a dremel in the port side of the stationary door to get it to pass over a guide so it would move all the way to the starboard side. The notch is invisible when you put it back together because it is against the frame on the port side. I can probably dig up the pictures if anyone wants them.
 
Irie308 said:
Alex it sounds crazy but I think my combination of the larger muffler and the check valve greatly reduces the sound on the exterior of the boat. Initially, before I added the larger muffler I thought the check valve was a muffler and it was pretty quiet as it was.
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Dean,
It actually makes sense to me. The check valve has a big enough can acting as an additional silencer. Now I understand why yours sounds quiter than mine.
 
Alex F said:
Dean,
It actually makes sense to me. The check valve has a big enough can acting as an additional silencer. Now I understand why yours sounds quiter than mine.
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Alex, I located the check valve at Defenders for less than $100. I will be installing one with my new generator in the spring.
 
Fellas i will be putting a deposite on a 2006 44DB Friday. 700 hrs Cummins QSC 500's.
we are excited. Now just need to sell my 390MY so i don't have 2 big boats this summer.
 
RBB said:
Fellas i will be putting a deposite on a 2006 44DB Friday. 700 hrs Cummins QSC 500's.
we are excited. Now just need to sell my 390MY so i don't have 2 big boats this summer.
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Sounds like fun to me, We enjoyed ours immensely. Good luck selling the MY. I couldn't bring myself to risk the expense of owning two boats and that has left us boat-less for three months now. There are worse things in life to endure but I am constantly scouring YW looking for the next boat.
Happy New Year!
 
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We sold our boat in June and took possession of our 44 DB in late September. Worst summer of my life boat-less.I would ask my wife, what do people do when they don’t have a boat? Happy now, can’t wait
 
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Mark.60 said:
We sold our boat in June and took possession of our 44 DB in late September. Worst summer of my life boat-less.I would ask my wife, what do people do when they don’t have a boat? Happy now, can’t wait
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Well I can tell you for sure that my honey do list at the ranch is getting shorter by the day:rolleyes:
 
Irie308 said:
Alex, now you have peaked my interest that you don't have one. The person who I chatted with ran the boat to FL after owning it for a while and that's when he had the water ingestion to the gen. I know you've done similar travels multiple times so curious what's different in your setup. I know when I'm fully loaded my exhaust port sits pretty close to the waterline. Based on the fact that the water shoots up through the drain ports from the cockpit I thought it was quite plausible that water cold build up in the muffler and make its way back to the gen. Curious if they changed the run of the exhaust line or raised the outlet at the water line. I was definitely puzzled as to why the PO had to replace the gen but finding out that I do have a check valve and hearing this story made sense. Mind you my gen is a 2008 model and when we purchased from the original owner in 2018 it only had 20 hrs on it, so clearly they didn't really run the gen.
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Irie308 said:
View attachment 96880
Yes, Attached is a photo of my check valve. Best I could get in tight quarters. Thought it was a muffler at first until closer inspection. I do have a rise in the exhaust tube coming off the muffler but can still the water making it above the rise Over a period of time in rough seas. Interesting still that some have a check valve and some don’t.
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Can you tell me the location of the check valve. I will be installing one with my new generator. I would guess between muffler and thru hull ?
 
Yes, it’s about 12-18” from the through hull.
 
Got down to the boat for the weekend, had planned to get organized to install check valve & 10” muffler on the next trip. Discovered it does have a check valve! This job just got easier & cheaper!.
Photo attached, about 4-6” from thru hull.
AD3D3397-0888-4653-A79E-2E1AB0C143B7.jpeg
 
Thanks for the picture it takes out the guess work.l see you have a freedom lift , how do you like it ? I am having a hard time deciding what system to use . I lick that it is removable as we swim off the back quite a bit and don’t take dinghy everywhere we go
 
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