Fuel Log

[Stu Jackson]

For awhile I've been noting that we keep a fuel log because our fuel gage doesn't work, but our engine hour meter certainly does.

This is a page of our fuel log.  It's on a spreadsheet, so all we do is enter the date, the engine hours, the fill amount in gallons and the cost, and the spreadsheet does the work.  If you look at the columns, you'll see it's pretty easy to figure out how to set it up.  As I suggested in a recent post (see: http://c34.org/bbs/index.php?topic=3824.0) you don't have to do this as conscientiously as we do, just try it for a few fill-ups and you'll know how much fuel your engine uses.

The reality is that OVERALL fuel consumption rarely varies. Of course, theoretically it would be between idle, cruising speed and WOT. But that's NOT how we use the engines in our boats. It really all averages out. And THAT'S the ONE number you need to know.

Added May 12, 2019:  Thanks to SFS from sbo.com:

Another rule of thumb if you have a diesel: Diesels burn about 1 liter per hour for every 10 horsepower being developed. This was borne out by our experience. Our Yanmar was rated at 23 hp at 3600 rpm. Therefore, at 2800 rpm I suspect I was developing about 17 hp, which would be 1.7 liters per hour. That converts to 0.449 gallons per hour.

To see it, right click on the attachment filename below, click on "Open in new window", click on Open (or save, your choice).

[Larry Robertie]

four gallons for 6 bucks... those were the days. 

[Stu Jackson]

Ah, Larry, you noticed!   

That's one of the reasons that I did NOT include a column for cost per gallon. 

[Craig Illman]

Guys - Even at $3/gallon, fueling the boat is a lot less onerous than filling the car!

Craig

[Ron Hill]

Stu : If I'd kept a log like your's mine would show:
Watermans diesel @$.50/gal and Road diesel at $.65/gal!!  "Read them and weep!"