CONTINUOUSWAVE

Hello. I currently have an 2006 Yamaha 70-HP two-stroke-power-cycle engine that runs very well. I’m considering buying a c.1985 Montauk 17 hull from my neighbor. I duck hunt a lot and regularly carry three people, 75 to 100 decoys, and a boat blind on the tidal rivers in and around the Chesapeake Bay.

It looks like most people put a 90-HP engine on their Montauk. I don’t see many with 70-HP engines I’m afraid the 70 will be underpowered while loaded.

On the other end of the spectrum I also have access to an 2003 Suzuki 140 that weighs 400-lbs. This exceeds the weight and horsepower limit.

I have seen examples of people putting larger motors on Boston Whaler boats.

Is [a 140-HP and 400-lbs engine] too much power and weight for a 17-foot hull?

Short answer: a 70-HP engine on a 17-footer is great for running solo.

When a 17-footer is loaded as you described, the boat can do 30-MPH if rigged right--but may be sluggish.

A 140-HP engine is doable. Some have done 150 to 200-HP.

You will want the battery in the console and when loaded, have heavy gear in the bow to counter the 400-lbs on the transom. One of my friends had a Honda 90 (more than 400-lbs) on his Montauk. Worked for him and his family.

I would mount the 140-HP all the way down, with a four-bladed propeller, and select the pitch to keep the boat from exceeding 50-MPH.

Thank you that is helpful

A c.1985 17-foot hull is now about 36-years-old. The original power rating maximum was 100-HP. The typical engine in c.1985 for a 100-HP engine would have been around 300-lbs.

To exceed the horsepower rating by 40-HP is a 40-percent increase in power over original maximum.

To exceed the typical c.1985 engine weight by 100-lbs is a 33-percent increase over original typical engine weight.

I doubt that the hull at age 36 is particularly STRONGER than when new, and it is more likely to be weaker.

As mentioned, the use of a 90-HP engine on the 17-foot hull is very common. The use of a 140-HP engine is not common.