FNM Diesel Install
Pretty dang cold today which got me wishing and thinking about getting back out on the salt. I thought I would share with you my experience of putting a FNM HPEP 300hp Diesel in my 27 Seasport Navigator (W/Flybridge) that weighs in at roughly 6400 lbs dry. With full tanks (160 gal) water, food and people and a dog she's over 8000lbs. I've had a chance to pour over the numbers from last season and I think you will find them pretty impressive. The FNM 300 is approximately 100 lbs lighter than a standard Chevy 350 block and literally hundreds of lbs lighter than the Volvo 6 banger that came out. I'm running a Bravo 2 diesel outdrive.
On average, in flat water with 1/2 tanks (approx 80 gal.) and 4 people (and a clean hull) I saw the following numbers:
24 MPH@ 3300 RMP 58%
26 MPH@ 3500 RMP, 65%
30 MPH@ 3800 RPM, 75%
34 MPH @ 4200 RPM, 100%
I do not have a Floscan or fuel flow gauge, but I calculated it several times. Again, this is on average. At 26 MPH with the same circumstances I burned 7-7.5 gallons/hour or 3.4 MPG. I know, seems unreal but that's how she penciled out. I ran her at 80% a few times and the burn rate jumped up to about 10-11 GPH.
I can tell you that this boat had never seen more than 24MPH prior to the install.
Speaking of installs, the folks at Frontier Fabrication (http://akfrontierfab.com/) in Wasilla were top shelf. Mel is very personable and put up with the many questions I had before and well after the install. He knew that the key to performance would be the prop selection and he spent an entire evening with us after his shop doors closed to dial in the correct prop. I think we pulled the boat and replaced the prop at least 4 times before the numbers were ideal.
I put almost 90 hours on the engine last summer without a single issue. I mean nothing. Not a drip, loose bolt, funky sound.....nothing.
PM me if you have any questions. Happy to help.
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