Fuel economy for a 470 on a 17' boat

[natemoore]

Finally! Finally! Got the family on the water today!

I pulled my kids around on a great big two person Budweiser float for three solid hours at WOT pretty much. Used 17.5 gallons of fuel.

Is that about right?

 

[Jmunk]

Re: Fuel economy for a 470 on a 17' boat

Any engine that operates at/near WOT for three hours is gonna drink a significant amount of fuel, 17.5 gal is probably a fair number thats a bit more then 5 gal/hour. You should be able to pull a tube at 1/2 throttle or less. I have a 180 Sea Ray with the 3.0l and and can pull a tube at less then 1/2 throttle once I get it the tube on plane. You might wanna read up on props and see if what you have is appropriate.

 

[stonyloam]

Re: Fuel economy for a 470 on a 17' boat

Well let's see. 17 foot boat, 470, WOT will be about 40+mph, say average 30 mph for 3 hours, 90 miles. About 5.1 MPG, doesn't seem bad for WOT pullin a tube, lots of starts and stops. Glad you are havin fun with the old 470

 

[natemoore]

Re: Fuel economy for a 470 on a 17' boat

Any engine that operates at/near WOT for three hours is gonna drink a significant amount of fuel, 17.5 gal is probably a fair number thats a bit more then 5 gal/hour. You should be able to pull a tube at 1/2 throttle or less. I have a 180 Sea Ray with the 3.0l and and can pull a tube at less then 1/2 throttle once I get it the tube on plane. You might wanna read up on props and see if what you have is appropriate.

I've been thinking I need to change props. I've been running about 25 kts at about 4500 rpm with the throttle lever at about 10 o'clock when firewalled is at 9 o'clock. According to my tach I could go well past 5000 rpms.

 

[a1nowell]

Re: Fuel economy for a 470 on a 17' boat

I believe 4400-4800 rpm is wot for a 470.

 

[HT32BSX115]

Re: Fuel economy for a 470 on a 17' boat

Finally! Finally! Got the family on the water today!

I pulled my kids around on a great big two person Budweiser float for three solid hours at WOT pretty much. Used 17.5 gallons of fuel.

Is that about right?

Um, I would think it's really not a good idea to run around at WOT for 3 hrs.....


just saying....

 

[natemoore]

Re: Fuel economy for a 470 on a 17' boat

4200-4600 rpm to be exact

 

[natemoore]

Re: Fuel economy for a 470 on a 17' boat

There are plenty of starts and stops when tubing, so it's not like I screamed down to Destin from Pensacola, but I understand what you're saying. WOT doesn't equal cruising speed.