Give me performance information for a 150 MONTAUK that weighs 950-lbs with a Yamaha F70.
Q1: what propeller will be best for a 150 MONTAUK with a Yamaha F70?
Q2: how does the performance of a 150 MONTAUK with a Yamaha F70 compare to the performance with the original Mercury 60-HP BIGFOOT engine?
150 MONTAUK Yamaha F70
Re: 150 MONTAUK Yamaha F70
The first generation 150 MONTAUK (up to 2016) has the same weight as the Montauk 17 at 950-lbs. For this reason I would suggest the following propellers for the F70 to start:
As for performance, the factory shows boat speed at WOT as 36-MPH with the standard Mercury 60-HP. With an F70, I calculate you should be able to reach 40 to 41-MPH.
The post-2016 150 MONTAUK weighs 200-lbs more (1,150-lbs), so I would drop two inches of pitch.
- 13 x 17 Yamaha Painted SS
- 13.25 x 14 Yamaha Performance Series
- 13-1/4 x 17 Turbo 1
- 13.25 x 14 PowerTech SCP
As for performance, the factory shows boat speed at WOT as 36-MPH with the standard Mercury 60-HP. With an F70, I calculate you should be able to reach 40 to 41-MPH.
The post-2016 150 MONTAUK weighs 200-lbs more (1,150-lbs), so I would drop two inches of pitch.
1992 Outrage 17
2019 E-TEC 90
2018 LoadRite 18280096VT
Member since 2003
2019 E-TEC 90
2018 LoadRite 18280096VT
Member since 2003
Re: 150 MONTAUK Yamaha F70
I don't have any first-hand experience from which to offer advice, but I do have two observations:
There is range of pitch in those four suggested propellers of three inches, from 14 pitch to 17 pitch. I suspect that some of the propellers may be three-bladed and others are four-bladed. That might account for the unusually wide range of pitches suggested.
You can calculate the effect of changes in horsepower or weight on boat speed with the calculator I have created using the experiences of naval architect George Crouch, which I call Crouch's Calculator. See
Crouch's Calculator
https://continuouswave.com/calculators/crouchCalc.php
Phil T wrote:... I would suggest the following propellers for the F70 to start.
- 13 x 17 Yamaha Painted SS
- 13.25 x 14 Yamaha Performance Series
- 13-1/4 x 17 Turbo 1
- 13.25 x 14 PowerTech SCP
There is range of pitch in those four suggested propellers of three inches, from 14 pitch to 17 pitch. I suspect that some of the propellers may be three-bladed and others are four-bladed. That might account for the unusually wide range of pitches suggested.
Assuming there was no change in total weight, an increase to 70-HP from 60-HP would tend to increase the boat speed by a ratio of (70/60)^0.5 or 1.08. This implies a new boat speed of 1.08 x 36 or 39-MPH. Also, any increase in weight due to the more powerful engine will tend to reduce boat speed.Phil T wrote:...the factory shows boat speed at WOT as 36-MPH with the standard Mercury 60-HP. With an F70, I calculate you should be able to reach 40 to 41-MPH.
You can calculate the effect of changes in horsepower or weight on boat speed with the calculator I have created using the experiences of naval architect George Crouch, which I call Crouch's Calculator. See
Crouch's Calculator
https://continuouswave.com/calculators/crouchCalc.php
Re: 150 MONTAUK Yamaha F70
All of the propellers I listed are three-bladed. The blade design differences explain the disparity in the pitch size.
1992 Outrage 17
2019 E-TEC 90
2018 LoadRite 18280096VT
Member since 2003
2019 E-TEC 90
2018 LoadRite 18280096VT
Member since 2003