Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Updated performance numbers for Suzuki DF140A on my 1986 18 Outrage

Posted by lowelife on 05/05/14 - 6:30 AM
#1

Updated performance numbers for Suzuki DF140A on my 1986 18 Outrage. These are pretty consistent with the first set I had. It has a Suzuki 14”/20” pitch SS prop. Conditions were light winds and 85 degrees.I boat mainly in brackish to salt water. 3/4 tank of fuel and just me on the boat with normal equipment. I have about 9 hours on it. MPH is with a handheld Garmin GPS. Engine is mounted in the middle of the five top wholes. Picture of mounting is on my personal page. Fuel consumption numbers seem too good to be true compared to my previous boats.

RPM MPH GPH
3500 21.1 2.5
4000 26.2 3.3
4500 30.3 4.5
5000 34.2 5.5
5500 38.1 7.1
6000 40.8 9.3
WOT is 6450 and 42.9 MPH.
I’m thinking about trying a 22” prop.

Posted by tom blinstrub on 05/05/14 - 7:38 AM
#2

Very impressive mpg figures! I assume you don't have bottom paint. I just bought a 1989 Outrage 18 and haven't repowered it yet. I was thinking of a 115 ETEC or Tohatsu. I was hoping to get 4-5 nautical mpg at 20 knots. I converted your 4000 rpm figures to knots. 22.7 knots at 4000 rpm for a mileage of 6.87 nautical mpg. Im not sure if my 16' Whaler is that good with a 50 hp Tohatsu TLDI. I would bet your getting over 10 mpg at idle.

Posted by egerrity on 05/05/14 - 8:51 AM
#3

Great numbers, and a great boat.. Enjoy

Posted by Phil T on 05/05/14 - 2:23 PM
#4

Is the WOT rpm number what you reached?

What is the WOT range of the motor?

If you are not reaching the upper 2/3rd of the WOT range I would consider a larger prop BUT before doing so, where is the anti-cavitation plate in relation to the hull? It should be ~ 1 - 1 1/2 inches above the keel.

If you raise the motor, you can expect 100-150 rpm increase for each hole you raise it.

Posted by Marko888 on 05/05/14 - 6:16 PM
#5

How is that engine height working? Are there any situations which cause the boat to lose grip, such as blow out in a turn?

Posted by rwethereyet on 05/05/14 - 6:31 PM
#6

I am using a 2012 Suzuki DF140 with 14 x 22 stainless prop. WOT is around 6000 RPM 42-43 MPH. My boat is the same hull as classic 18...the motor is not the "A" version. Try the 22" prop for comparison. There was no question when I compared sizes.......

Posted by lowelife on 05/06/14 - 5:19 AM
#7

The boat does not have bottom paint…..I hit 6450 RPM’s and when I did the “rev limit” message appeared on the gauge which is consistent with what the owner’s manual states will happen…….manual states “full throttle operating range” is 5600-6200……in my opinion the boat is performing very well-I intentionally did some hard turns trying to get some prop slip but it never happened……right now I don’t see any reason to change the motor height…I’m going to try a 22” SS prop and see what I get….planning on asking about the fuel consumption numbers when I take it for the 10 hour service-they just seem too good to be true.

Posted by Phil T on 05/06/14 - 5:23 AM
#8

I would try the 22'' prop since you are exceeding the recommended WOT rpm's.

Posted by tedious on 05/06/14 - 6:19 AM
#9

How are you measuring the fuel consumption? Separate flow meter, or as reported by the motor?

Tim

Posted by rwethereyet on 05/06/14 - 10:33 AM
#10

I also experience incredible fuel economy...as measured by the "smis" digital Suzuki guage. Unfortunately, I can't quote numbers.....

Posted by lowelife on 05/06/14 - 2:55 PM
#11

Fuel consumption numbers are from the Suzuki SMIS gauge (modular multi-function gauge).

Posted by lowelife on 05/14/14 - 12:55 PM
#12

I took my boat to the Suzuki dealer for the initial engine service and to have the 20” prop swapped for a 22” prop. I picked it up today. Hopefully I’ll be able to run it this weekend and see how it runs with a 22” prop. The dealer states the fuel consumption numbers I’m getting on the SMIS gauge are correct. For what it’s worth, when I installed the new DF140A in early April, the fuel tank on the boat was full. I stopped on the way home today and filled it up again. It took almost 31 gals. I have 11.8 engine hours on those 31 gals. I don’t know how many mile I ran since I don’t have a permanent GPS on the boat yet.

Posted by Marko888 on 07/02/14 - 11:08 PM
#13

I'm about to mount my DF140A on my Outrage 18, and am curious if your performance changed much with the 22p propeller?

Posted by lowelife on 07/03/14 - 12:07 PM
#14

WOT RPM's are now 6200 vs. 6450 with the 20. WOT speed is now 45+ vs. 43. Fuel burn rate appears to have gone up a little across all RPM's except higher end where it went up more. I just this week installed a new Garmin 50DV GPS and plan on checking the engine performance numbers again. I'll post again if it changes much.

Posted by Marko888 on 07/03/14 - 12:30 PM
#15

Thanks for the update.

Did the holeshot change much with the switch to the 22p prop?

How happy are you with the current engine height? Do you think it could go higher?

Mark