25' Foot Boat Range

[212s]

Advance apologies if this subject has already been beat to death- but I have not seen it yet . . . .
When a lot of time and distance is spent at low speeds like 5 - 15 mph, in no-wake zones or cocktail cruising, etc, is there any fuel-consumption advantage to running on one engine instead of both ?
It seems intuitive that one engine at slow speeds would result in better mpg numbers; but is that true? Has anyone tried it ?

Haven't tried it but cutting thrust in half would likely mean speed is cut - due to less resistance at low speeds one engine would mean probably 1/3 loss of no wake speeds so maybe 5 down to 3.5 mph, and puttering around doesn't use much fuel - best mileage comes at idle speeds. At idle I can putter along all day and hardly use any fuel, about 30 miles with only 12 gals consumed over the course of 6 hours. Same applies to our old I/O drive where we could putter around all day and not use much fuel. And as someone else mentioned, perhaps less maneuvering control which could be the difference between a close call and an accident if you're not paying attention. Keep in mind that for fuel consumption numbers, a single supercharged engine uses about the same fuel as twin normally aspirated engines and gives similar performance in the 19 and 21 footers.

I wouldn't worry about it at all. Toodle around if you want, and crack it open when you want. The only time I would use one engine is during a failure and I have to limp back home. Something I do as well is start and stop in the same order to keep the hours meters the same...I'm a little OCD about stuff like that.

 

[MilesPrower]

Ok edit number 2 - page 66 is what my screen looks like. The pages you were referring to are for the 210 series which have tachs and a different display. Here's a screenshot of my manual and what I remember seeing:

View attachment 138433

Doh! I must've read the manual incorrectly, as I thought it was describing the screen for the 212 series. Sorry for getting your hopes up.

It's a shame that Yamaha chose to remove the option to display Gallons Used on the 212. If I didn't have that feature, I'd have range anxiety a couple hours after each fill-up, especially when I head offshore.

 

[212s]

Doh! I must've read the manual incorrectly, as I thought it was describing the screen for the 212 series. Sorry for getting your hopes up.

Yeah shame on you for that! I got all amped up!

It's a shame that Yamaha chose to remove the option to display Gallons Used on the 212. If I didn't have that feature, I'd have range anxiety a couple hours after each fill-up, especially when I head offshore.

It's ok, the option is still there, just under the Trip Info screen. After I get the chartplotter installed, I can change the Connext screen as I want.