bertram31.com

Hi guys, this is my first message here :)

My name is David, from Italy (sorry for my not perfect english!) and I own a 30 Bertram Moppie:



The boat is arrived just few days ago and I'm discovering it step by step...The first answer is on the fuel consumption...it's equipped with 2 Cummins bta5-9 @ 370HP, almost new with just 300 hours.

Reading the websites and the boat test, the consumpion should be around 10gph at 2000rpm and ~20knots, instead I got a 15gph at 2000rpm....So, it's normal or there is some mistakes?

Because in italy, with diesel price at 1.60 euros PER LITER (6 euros / 7,8$ per gallon) passing from 10gph to 15gph in cruise speed is a big difference :D

thank you all

David

Beautiful Boat David!!!!!!!!

thank you :)

David,

Welcome aboard. Are those fuel burn numbers per engine or total? I have 300hp B series and I burn 20gph (10 per side) at 2400rpms and I get 23-24 knots. You should burn something similar to that, as the fuel curves for all turbo charged and after-cooler B-series is very similar. While there are small diferrences between the 330B's and 370B's, the main one is a different setting on the injection pump that allows your engines to turn an additional 300rpms at the top. If you're saying your burning 15gph total (7.5 per side) at 2000rpms, that makes sense.

Fuel burn numbers are like mpg ratings on new cars here in the US. They are estimated on absolute best case scenario which hardly ever translates to real world usage.

How are you reading your fuel burn, calculating or by flow meters?

Don't worry our english ain't so hot either.

I got also a floscan but for now it's not working, I will fix it asap...

for now I have just measured the fuel burned "refuel after refuel"...but maybe there is a problem too because the fuel indicator it's damaged...I have to check the float

Check out Isspro.

http://isspro.mybigcommerce.com/fuel-le ... red&page=3

You'll have to contact them for the right size, but they work well.

David, I have the same engines, haven't launched the boat yet, I have been shooting for 15-18 gph combined, I would be thrilled with 15 gph, my outboard burned 17 gph in half the boat..BH

I'm not sure how you are calculating the burn but 2000 might be on the back side of your best burn per mpg or kpl in your case. She may prove a little more efficient at 2100 or 2250 let all that horsepower and torque let the hull work for you a bit more at those speeds. Rated fuel burn at given rpm is very generic, these deep vee bottoms need some speed to allow the strakes to begin adding lift and efficiency to the hull form.

Also first things first are the air filters clean?
Does the boat make rated rpm at full throttle?
No shakes or otherwise noticeable vibrations?

Chasing economy in a boat is a war of inches, sometimes it is just better to reach in your wallet accept defeat and have fun. Damn the torpedoes and open the grappa just have fun

jp has it right 2250 to 2300rpm is minimum rpm. (bottom of torque curve) . under this speed boat fall off of outside strakes and water dynamics takes it toll in slowing down boat speed.i have driven this 30' Moppie a long distance for a delivery a few years back .no tower boat ran 30knt. wot in 2' ocean waves. 15-18 gph sounds about right .

check this...

http://img28.imageshack.us/img28/984/be ... etest3.jpg" onclick="window.open(this.href);return false;

This is a test of the same boat with 3 different brand engines...

Its real difficult to measure fuel burn just by fuel in/out of tank other than generalization. Your best burn rate for your boat may not be the rpm as indicated by sea trial reports and you may have to experiment as indicated by JP and Bob.

Current, sea temp and water depth have effect on boats and how they perform besides boat loading. I ran into this with boats manufactured in EU and imported to the US.

A few even failed to get on plane here in the warm water of S Florida.

There have been numerous law suits by consumers against boat manufacturers due to published performance data and once the boat was delivered, it failed to live up to.

Get your floscan fixed. I was a distributor for them for almost 20 years. Cummins will use the high capacity system.
Know em backwards and forwards. Just ask questions here.