Proper HP for a Boston Whaler

[capngeo]

Boston Whalers... One of my favorites; I've had about ten of them! My most favorite was a 13' with a Johnrude 50 on the back (yes I know it was overpowered, but the grin factor was priceless).

Were I to make the attempt at making one an inboard, it would be jet drive. That said, the slow speed of most small Diesels rules out the use of a jet. I get the OP's desire to use Diesel, but it would never really have good performance; the power-to-weight ratio is just too low. As others have mentioned, the displacement hull speed of ANY Whaler is very slow.

[hsi88]

Originally Posted by Sailuke

I saw a youtube video of a man with an Atomic 4 30hp in a 14 footer and it only went around 8 knots.

Have to believe the guy in the video still had the sailboat prop on the engine. 30 HP with the torque of a diesel might not have the throttle response of a big 2 stroke, but should be able to scoot a 16 footer along at a pretty good clip with more prop. Except for the space it eats up and weight, I would think the combination would make a decent little cruiser.

[PortClydeMe]

Originally Posted by Chuck Hawley

If you agree that powerboats generally have three modes of operation: displacement, semi-displacement, and planing, you would need three different levels of horsepower to achieve each mode.

A 16' Whaler is not a barge. They float and move along just fine. Here's how you simplify the problem. Not too much thinking needed. Add a 55+hp outboard. Start engine. Look at the Morse controls. Think about where you want to go, and how fast. Then use low, more, or full throttle. It's actually that simple.

Inboard diesel engine?? "cough"

Anyway, since post #4 it appears that Luke went sailing. Or maybe he's out shopping for an outboard. Good thing.

[Pete7]

A run around will require 15hp per tonne to plane, but we are talking 15-20 knots which is hardly sparkling and a medium sized outboard will be alot more fun.

The resale value afterwards will of course be zip and the work required cutting out the deck and laminating in the engine beds etc, well I wouldn't do it.

Pete

[denverd0n]

Originally Posted by Pete7

The resale value afterwards will of course be zip...

Good point. Whalers, in general, hold their resale value extremely well. Not if you butcher one in this way, though.

[dgz3]

If you have come here looking for advise, here it is; don't. Just don't. You will ruin everything that is good about the 16 Whaler and get nothing in return. You will spend a lot of money, waste a lot of time, and go to a lot of trouble to create a boat completely useless for any purpose. And it will be worth absolutely nothing when you are done.
Sell the Whaler to someone who wants one for what it is. Then buy the boat you really want and need for your use.

[nolfi]

Dont do it...... Better yet surround yourself in an electric fence, wait for wind to pick up then pee as hard and long as possible.... This way youll of done less harm to the world than repower the whaler