15hp mercury 4 stroke prop question

[hwindle]

Re: 15hp mercury 4 stroke prop question

Yes. I traded the 15hp for a 25, which also has power trim and tilt. I haven't taken it out yet, as I just got it back yesterday. I have also bought some more hatch covers, and will keep removing water logged foam. It shouldn't be as big a deal with the extra Hp now, but I still want to get it out.

 

[steelespike]

Re: 15hp mercury 4 stroke prop question

Once lightened up I think 30+ might be possible.

 

[Swinerton]

Re: 15hp mercury 4 stroke prop question

The 25HP with PTT, will still underpower a boat that heavy. As for hitting 30mph, never.... You will be lucky to see 18mph. It will be much nicer than the 15hp for sure.

No matter what you did with the 15hp 4-stroke, it is not going to push a boat that heavy nicely.

Heck my 25hp four stroke, is way too small for my 14' Fisherman, that is about 1300lbs on the water. A 40hp is what it needs.

 

[steelespike]

Re: 15hp mercury 4 stroke prop question

The 25HP with PTT, will still underpower a boat that heavy. As for hitting 30mph, never.... You will be lucky to see 18mph. It will be much nicer than the 15hp for sure.

No matter what you did with the 15hp 4-stroke, it is not going to push a boat that heavy nicely.

Heck my 25hp four stroke, is way too small for my 14' Fisherman, that is about 1300lbs on the water. A 40hp is what it needs.

I was a little over optimistic but it's been me experience that a 700 lb glass boat would be as fast or faster than
an aluminum boat that is actually somewhat lighter. Also a boat with a good big footprint will do better than a smaller boat loaded the same. our 18ft Crestliner utility with an old Gale 25 would plane easily with 6 adults and light gear.
No special prop.
Probably 18 or 20 mph.The same motor would struggle on a 15ft Lone Star utility with 4 adults.
There is a 25 Evinrude test with an aluminum 16 footer at 1000lbs all up runs a shade over 31.
Of course we will be at more than that With this boat but could be respectable.Hopefully being glass will help once on plane.

 

[Swinerton]

Re: 15hp mercury 4 stroke prop question

There is a 25 Evinrude test with an aluminum 16 footer at 1000lbs all up runs a shade over 31.
Of course we will be at more than that With this boat but could be respectable.Hopefully being glass will help once on plane.

WOW.... oh yeah..... one more thing.. WOW.... How in the world?????? I assume this was a late model E-tec, and not your run of the mill 4 stroke.

 

[steelespike]

Re: 15hp mercury 4 stroke prop question

It was indeed a 25 Etec, But I think any solid 25 should manage good numbers.Our 15 year old, at the time, Gale
did well ,even getting us up on skies using a 100 lb adult spotter.

 

[Swinerton]

Re: 15hp mercury 4 stroke prop question

It was indeed a 25 Etec, But I think any solid 25 should manage good numbers.Our 15 year old, at the time, Gale
did well ,even getting us up on skies using a 100 lb adult spotter.

I need to find an E-tec on the side of the road.
I still think dealer's putting on 25hp four strokes on boats that oppose over a 1300lb load is ridiculous, just to make a package price look better.

 

[hwindle]

Re: 15hp mercury 4 stroke prop question

I will find out Saturday. On the Sundance website http://www.sundanceboats.com/modeldetail.php?subid=MTQy, they tested this boat with a 25hp, a 40, and a 50. The 25 hp did 28 mph, and the 40 did 32 mph but got on plane in a little less than 1/2 the time as the 25. I am going to drill more holes through the wet foam Friday, and maybe get another 10-20 lbs out. When I am done, it will at least be able to get air to all the wet foam, and any excess water that might actually want to drain out will be able to. I am hoping to find another pocket of loose water, but am not betting on it.

 

[hwindle]

Re: 15hp mercury 4 stroke prop question

To close this thread out, first of all thank you all for your comments. I took the 25hp big foot out yesterday for the first time, and it indeed will plane the boat. I didn't have the GPS, so can only say it felt like at least 20 mph, but I wouldn't bet a large sum on it. Hard to believe that 10 more HP would make that much difference. I was so happy for the first hour, until it lost power and blew oil smoke, which then stopped-the smoking not the motor. I thought the motor had lunched itself, but then it ran good, until it did it again.
Anyway, I have posted about this in the Mercury outboard section. Thanks again for all your comments, and the internet is definitely a good thing, even for old farts like me.

 

[hwindle]

Re: 15hp mercury 4 stroke prop question

I took it out yesterday with a GPS, and with my wife and I, we hit 21 MPH @5,400 RPM's. We finally have a real boat.

 

[anzomcik]

Re: 15hp mercury 4 stroke prop question

Glad to hear it worked out in the end. 21 is a good speed for that 25hp. Thats what my boat did when it had a 25hp. You should be very pleased with that setup