OMC 57 Gas Consumption

"I have just bought a 1988 Bay

"I have just bought a 1988 Bayliner 2556 command bridge fitted with a 5.7 OMC Cobra engine and drive both of which were replaced with rebuilt units in 2004. My question concerns fuel consumption. I live in the UK and pay the equivalent of $10 a gallon for gas. The boat has a top speed of 24 knots and a cruising speed of 17 knots, what sort of gas consumption per hour should i expect for these speeds. I also think the engine may be slightly over propped as it takes about 30 seconds to get on the plane.

Any advise is most welcome."

"I dunno about overpropped, I

"I dunno about overpropped, I think it's more a situation of underpowered as so many Bayliners are....You should prop the boat to run between 4200 rpm and 4600 rpm at WOT with the engine properly tuned and running well.

Fuel consumption? I would guess somewhere around 7 to 9 imperial gallons per hour cruising, up to about 14 GPH running full out. That's a wild guess - hard to say as there are so many variables.

You now own a Cobra drive, so go do the required reading:
www.hastings.org/~stuart/cobra"

"Definatley seems like an unde

"Definatley seems like an underpower issue. My Chris Craft 245 takes 10 - 12 seconds to get on plane with a 5.7 Cobra. It is considered a performance cuddy, not near the weight of your cruiser. 30 seconds does not seem unresonable for that hull and engine combo. I get around 8 GPH while cruising at 25 knots. It goes up to 13 @ 35 knots."

"Thanks for the info. With reg

"Thanks for the info. With regards to the time taken to get on the plane, it may be me not using the trim tabs correctly, My previous boats have all been smaller and lighter without tabs. Am going to play around with these on Saturday."

"I dont think you can use spee

"I dont think you can use speed as an indicator of fuel consumption, when you are comparing it to different boats, hull designs, and weight. Its really engine rpms. A 5.7 4 barrel is supposed to burn about 9 gallons per hour @ 3000 rpms, and 21 WOT. If I remember correctly."