Rotax 657 upgrade

[SPEEDSTER95]

I have a 95 speedster with 2 x 657 ( 85HP ) motors.Both motors and pumps have recently been o/hauled ( at least thats what I'm told by the guy I bought it from.)
My question is: Can I replace these engines with 155 HP motors. If so, do I have to change pumps , impellers etc.
Thanks in advance
Greg.
Not gonna do it yet. Just mulling over the thought as I want to do plenty of research before I commit.

 

[timmyboy76]

657=80hp. which the 717 motors will bolt directly there. Anything else, will take some/difficult modding...motor mount placement..etc. Also, all the electrical will need replaced.

 

[bigler]

and the cost would be kinda ridiculous. you would be better off selling your boat and buying something with twin 110s. ive seen alot of them for sale pretty reasonable.

 

[SPEEDSTER95]

Thanks guys. I am gonna double check what the engines are. The manual says 657 but the previous owner seems to think 717.

 

[Dr Honda]

Thanks guys. I am gonna double check what the engines are. The manual says 657 but the previous owner seems to think 717.

just look at the tag on the mag housing. it has the size of the engine. It will have 657’s unless they were swapped out. 96 was the first year of the 720 engine in the boats.

 

[SPEEDSTER95]

Thanks Dr. Will do. I have had boats most of my adult life but this is the first jet boat, so as you can see I am still learning.