Re-Power

[southpointe]

Does anyone know the approx weight of a 1998 Johnson 225 (carburated)

I want to repower my 20'Grady with a 150 Yamaha 4 stroke - any other concerns?

Will the mechanical steering be OK?

thanks

 

[Silvertip]

Re: Re-Power

If the performance was adequate with the 225 two stroke, you will be very disappointed with a 150 four stroke. You are cutting power nearly in half and may in effect shoot yourself in the foot so to speak. Severely underpowering a boat results in the new motor having to run with much more throttle application whereas a more powerful motor can simply loaf along providing better economy (or close to it) in the process. Steering will not be an issue but engine controls and instruments will be. I feel you need to research this swap a little more and especially look for boat tests for the same boat and engine combination. Look at the Yamaha web site for test reports. I did a quick check and the few 20 foot Grady's were powered by 225's.

 

[dingbat]

Re: Re-Power

I'm assuming that you?re looking to repower a 208.

Most find the 208 with a Yami 150 to be adequate power in most situations. You should end up with a top speed of right around 38 kts. I had a 175 HP on my 208 and it ran right around 40 kts. with normal load and 36 kts fully loaded.

I wouldn't worry about the steering. I have manual steering on my 226 with a 200HP and have no problems with torque feedback. A good 4 blade prop works wonders should you like a bit more control.

As for the weight, your 225 weighs 460 lbs