How Much HP?

[Mainiac]

I have a 18' Aluminum boat, my engine seems to be toast....can't find the plate on the boat which tells the max HP.... if anyone has an idea on what she'll handle it would be appreciated! the "toasted" motor is a 65hp Merc.

 

[Silvertip]

Re: How Much HP?

Boat make and model would certainly help. An 18 foot Jon is very different than an 18 foot side console vs and 18 foot run about.

 

[steelespike]

Re: How Much HP?

My 18ft 57 Crestliner utility 330lbs is rated at 70hp. yes 70 hp.My 77 18ft Crestliner
375lbs is rated at 55 hp.

 

[d.boat]

Re: How Much HP?

The coast guard has a formula for figuring the max. HP - it is a simple calculation using length, width, and transom height.

Here's a page that (I think) shows how to calculate it.

http://files.dnr.state.mn.us/education_safety/safety/boatwater/backyardboatbuilders.pdf