1987 Starcraft 22.1 Islander hardtop w/ 3.0L 140

[viper1]

We'll finally fixed and on the water. Had it out today for the first time. We had talked about the prop before as the guy had some wild claims of speed and fuel economy. Had it out today, 30 MPH at 3000 Rpm's. Seemed to run good. Is this about right? If so what kind of real world fuel use can i expect while cruising and trolling. I m sure WOT wouldn't be cheap. But I generally pull back to about 20 mph after getting on plane. This seemed to have a sweet spot there any way. Some one said 5 gal per hour at 20 MPH and maybe 2-3 at 2.0 MPH and a whopping 14 gal per hour WOT. Is this any where close for this boat?

 

[Rick Stephens]

Your boat is plenty fast. I get 10 mph slower than that at 3k.

Your numbers are a lot worse than reality. I run for an hour up lake to fish. Switch to the 10 horse for trolling. Switch back and pull the kids around for a hour or two, fish a couple more (kicker is plumbed to main tank). Run back an hour. Use 7 gallons on the day. If I just fish, then somedays s all day with a couple hours of cruise is under 4 gal. 3.0lmotors with throttle kept lightly leaned on should be very frugal on go juice.

I have at most, on long day, used about 12 gal.

 

[Watermann]

Yeah Viper that's really good for a 3.0 to run 30 at 3k RPM in your Islander. My Chief's 205 HP 4.3L with a 23p Black Diamond prop cruises 35 at 3300. Over 40 using the secondaries really guzzles the juice. :lol:

Every boat has a sweet spot where the motor isn't working hard or lugging where you can cover some distance and not drain the fuel tank.

Glad to hear you got out for some good sea trials :thumb:

 

[steelespike]

We'll finally fixed and on the water. Had it out today for the first time. We had talked about the prop before as the guy had some wild claims of speed and fuel economy. Had it out today, 30 MPH at 3000 Rpm's. Seemed to run good. Is this about right? If so what kind of real world fuel use can i expect while cruising and trolling. I m sure WOT wouldn't be cheap. But I generally pull back to about 20 mph after getting on plane. This seemed to have a sweet spot there any way. Some one said 5 gal per hour at 20 MPH and maybe 2-3 at 2.0 MPH and a whopping 14 gal per hour WOT. Is this any where close for this boat?

We need a lightly loaded wot run,get us the rpm and gps speed.and prop size,usually under the prop nut.
Your wot rpm should be 4400 to 4800 rpm. speed 35-38.

 

[steelespike]

Mileage at wot would be about 12 to 14% of your rated hp about 17 gph. Of course partial throttle will be a savings. With some experimentation you could find the ideal cruising speed.