I have both a 9hp (converted to a 13hp) GDLT (galvanized frame) and a 15hp GDLT (painted frame). The 9hp frame is a 2004 model with very little hours (Less than 25) and the 15hp frame is a 1997 model with many hours (over 300). Due to the fact that I am running a larger boat in brackish water, I would like to make the conversion to the larger motor on the galvanized frame. I have measured both frames and it appears that the 15hp motor will fit on the 9hp frame, with the only difference being the distance from the back of the motor to the pivot point on the transom. The 9hp motor is mounted further away from the pivot point. I am assuming that by doing so, the weight distribution will be such that it will take more effort on the drivers part to keep the prop in the water. Other than this, is there any other drawback from making the swap? Your opinions and experience both welcome. I am running the set-up on a 16/36 GD duck skiff, and eventually want to put a 23hp SD on the boat. Is it even worth my time and effort in doing the change?

Is your center height to the PTO of both frames the same? My nine horse Robin engines are a little smaller than my 14 horse Robin engines.

Mark F. Cheney

It appears that the motors are the same dimensionally, including the distance from shaft centerline to the bottom of the motor.

I would make the swap if you have the motors. It becomes more subjective if you have to buy the bigger motor, what's it worth to you?

Mark F. Cheney