Whaler Central - Boston Whaler Boat Information and Photos

Posted by Reel Easy on 07/07/14 - 10:49 AM

I am running twin Yamaha 90s 1988 model on a 1974 Outrage 21 with light equipment, and about 20 gallons of fuel, and two adults. Might anyone have knowledge as to what kind of fuel economy I should expect at mid to open throttle. Max RPM with current props is 5600. Perhaps economy is not an appropriate description. Thanks for your help

Posted by swebre on 07/07/14 - 12:12 PM

I have a 1978, 21' Revenge w/ an 1988 Mariner 175 that burns 8.3 gph @ 30 mph (gps) @ 3600 rpm w/ 2 adults and full fuel (40 gals). Not identical, but our hulls have the same bottom profile.

From an economy standpoint, I'm likely a tad heavier overall (bad) w/ more weight toward the bow (bad) but w/ a single engine (good).

I'd expect you are in the 7 to 8 gph range at the same speed.

Should also mention that at WOT (5600) I see 50 mph burning right at 20 gph.

Good luck!

(please follow guideline #1 on the front page and use the full 4 digit year for everything)

Edited by Joe Kriz on 07/07/14 - 1:07 PM

Posted by Reel Easy on 07/07/14 - 12:53 PM

Thanks swebre. That gives me a good idea of consumption expectations. Seems that those last 2000 revs get pretty pricey. I am surprised there is that much difference. Thanks for your input.

Posted by swebre on 07/07/14 - 1:54 PM

Yep. That extra speed does cost. And while I'll admit that I really don't NEED it, it is fun to make a short bonzi run now and then.

Posted by gchuba on 07/07/14 - 6:54 PM

I have a 1979 22ft Revenge. My previous power was a 1980 235hp. Johnson. Fuel consumption with my motor at wide open throttle (5600 rpm) was reasonable (cannot remember exact fuel use, close to modern motors). The low idles is what kills the mileage. I would watch the gauge move for trawling. The older motors generally do better for fuel consumption at higher rpm. I would have to fire up the motor and clean the carburetors mid trawling to prevent flooding/stalling.

Garris

Edit: Reel Easy, with your set up, if I was going out for a day of boating I would top off the fuel as a must

Swebre: how did you determine fuel consumption

Edited by gchuba on 07/08/14 - 7:32 AM

Posted by Reel Easy on 07/08/14 - 7:54 AM

Thanks gchuba. Most of my use is on a small inland lake where we life. However I do look forward to some day trips in Lake Michigan, Lake Erie and the Cheboygan River over to Mackinac Island. Certainly would have full 40 gallons for those events. I took out the two 15 gal. saddle tanks when I got the boat as I dont plan on ever needing that much fuel. I still have them if anyone has interest.

Posted by gchuba on 07/08/14 - 8:09 AM

Is yours a 20 gallon tank, or 40? You may want to hold onto those saddle tanks (especially if it a custom, safe, nice looking set up). Run tour boat a bit and start gauging the fuel use. Previous owner got them for a reason.

Garris

Posted by Reel Easy on 07/08/14 - 8:43 AM

My internal tank is 40 gals. The Outrage was originally rigged in Florida in 1974 totally for fishing. In 1977 it was purchased by the assistant basketball coach at the University of Michigan who owned a cottage in the North Channel of Lake Huron in Canada. He fished the boat quite a bit and I suspect could have used the additional fuel. Problem was that they were not installed correctly and leaked badly at the filler neck. Consequently they were unusable as they were. The tanks themselves are in great shape. Seems the original saddles from BW were oval while these are rectangular. I am guessing they were after market/special built. For the infrequent times I might need additional fuel, I would bring portable containers.