Need advice. Looking at 44DB.

RiverGalsMan

RiverGalsMan

Member
Nov 3, 2006
327
Shady Side, Maryland
Boat Info
2007 44 DB
Engines
Cummins QSC 500
Thinking of moving up to a 44 DB with the QSC500 engines. Any advice or things to look out for? This would be my first experience with a flying bridge and diesel power. Thanks in advance for any input.
 
Well, we've pretty much decided we're going to do this. At this point I could really use some pointers on what to look for on the boat. Things like burn rates/speeds, engine/systems features, accessibility of stuff in the engine room, those sorts of things. We're sea trialing Friday.
 
Larry,
I think if you search for Festivus' posts he has some good info on his fuel burn with the QSC 500s. i think he was in the 30-35 GPH / 28 knot range but I am not sure. He also posted a really interesting video clip of the boat looking aft as it came on plane. i think I heard the turbos wind up at aorund the 12 or 13 second point of the clip.

Enjoy the sea trial.

Skip
 
CJ Martin said:
Larry,

What are you doing with the 38? Trading or selling?

-CJ
Click to expand...

I wondered the same thing.....I would love to have the room in your boat...but probably not quite ready to spend that much yet....
 
Skip, I've actually had two long conversations with Tim (Prodigalson/Festivus) about the 44DB. The info he's given me has helped me make this decision.

I'm trading in the 38 on a demo DB. I originally got such a good deal on the 38, and it's still relatively new, that I'm not taking much of a hit.

It's funny... we got the 38 about 8 months ago and back then it was the nicest, biggest, prettiest boat ever! Today it's small, I don't fit in the head, the whole gas vs diesel thing, my mom can't go down into the cabin (she's almost 80,) there's not enough light down there, not enough storage, you name it... I've told the admiral "THIS IS THE LAST BOAT!", but who am I kidding :wink:
 
Well, I did my sea trial yesterday and let me start out by saying WOW. The performance, the view, the room. This is THE boat. The LAST boat :smt043 EVER!

Anyway, I've got a coulpe of questions for the diesel gang and for Prodigalson. The boat did 6.5 MPH at idle (600 RPM, less than 1 GPH!) That's 6 MPG at a very slow speed. That's pretty awsome for no wake zones. How long can I run like that without adversely affecting the engines? Diesels need to run under load, right? Also, at cruise, we ran about 25 MPH at 2200 RPM, but burning 32 GPH total. Is that about right? I seem to remember seeing a post where Festivus is doing better than that. Also, I wonder because at WOT she went all the way to 2700 RPM and stayed there. Could she be slightly under-propped or will the WOT RPMs come down once we load her up with stuff.

So many questions :smt017
 
Larry-
I'm glad you enjoyed the ride!

I make no claim to be a diesel expert, so I'll let someone else tackle the long-range at low load question. I use setting #1 on the "cruise control" to run the engines at 80% load (based upon the SmartCraft calculations). This equates to 2420 RPM. At that RPM we cruise at 26+ knots (30 MPH) and burn 40 GPH. For a fuel "efficiency" :lol: of 0.65 nMPG or 0.75 sMPG.

By my fuel log, across all running conditions (i.e. measured by fuel consumption / elapsed engine hours), we're averaging 22 GPH, but I see that trending up as we do more "at speed" running.

On my boat, "Cruise 2" is set to about 2200 RPM, which gives me a speed of 22 knots (25 MPH) at a fuel burn of 34 GPH at a 70% load, which equates to roughly the same fuel efficiency.

All else being equal, I'd rather go faster and run the engines at their preferred load range, so we run at 26 knots (except for when we're travelling with some of our express cruiser buddies who can't keep up :thumbsup: )

Also, 2700 is the max RPM so it seems logical that you would top out at that speed.
 
Tim, OK, good. It looks like we're getting similar performance. I was doing the numbers in my head while we were riding around and they we're all coming up about .75 MPG. For some reason I thought you we're doing better than that (not too shabby for a 15 ton boat :thumbsup: , though.)

I thought the WOT RPMs were 2600? That's what the Cummins web site has listed, anyway. :smt017
 
I have not looked at the specs for your boat but in general when an engine manufacturer specs WOT he is specifying the minimum RPM that should be achieved at WOT. One of the reasons this is specified is to insure that the boat is not over propped which in turn may over load the engines and lead to reduced engine life. My engines are spec'd at 2600 RPM and I achieve 2750 RPM at WOT with a clean bottom, full tank of fuel etc. It is better to be slightly under propped then over propped.
 
Larry-

2600 is the "rated RPM" in the specs, not sure that's the max. And to be clear, my actual max is 2680. Not that that really matters.

Also, I think I mentioned this to you already, but compared to my old boat with 8.1 gassers, this boat is almost half as much to run on a $/mile basis. I chose that metric becuase it captures the faster speed, higher efficiency and lower fuel cost. And ultimately, here to there is always the same number of miles.. . so as I tell my wife, the more we run, the more we save!

So anyway, are you bringing her to Aquapalooza?
 
Thanks for clearing the WOT thing up. I feel a lot better knowing there's nothing "off." Especially since she's got 150 hours already. I'd hate to think she ran 150 hours out of balance. I seem to remember that in the Smartcraft there was a screen for % power (or load or something like that.) I need to take a closer look at that.

About Aquapalooza, It's looking like I can't make it. We don't settle on the boat until next week and the dealer asked me to keep her at his yard for a couple of weeks after that to make it easy to fix whatever little things come up. It makes sense. Maybe we can get some momentum up for a CSR "MiniLooza" somewhere up in the bay?
 
Anything that ends in "looza" is always good with me. I'm open every weekend in August. Need to stay north to avoid the dreaded sea nettles!
 
I dont mean to hijack this thread but,

We seatrialed a 44 DB today. WOW! The boat is awesome. I think I have found religion with the diesels. I can't say enough good things about the boat but, at the end of the day I am still very happy with the 320. Prodigalson, if you don't mind my asking about how much did you pay for your 44, The dealer is giving us 575,000 as the bottom line so far, does this seem about normal and fair? It is optioned fairly well but it isn't completely decked out.
 
Well, the 38 has been successfully delivered to Prince William Marina for - hopefully - an eventual trade in for the 44DB. Still waiting for final approval from the bank and everyone is at some big sales meeting at Sea Ray so I can't get a status. The anticipation is killing me :huh:
 
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