I would like to know if you need to transfer anything besides the engine when installing a js750 engine into a js 440/550 hull.

 

How about the CDI and other electronic stuff?
Will the 750 motor bracket fit on the motor mounts of the 440 on the hull floor?

 

I wasn't sure if the stock 440 electrics would work. I need a conversion plate for the 750 engine. I need to do so more research. Thanks.

 

Not only you need a correct CDI (for correct ignition timing), you will also have to think about right sized impeller and pump for the increased power. Stock 440 pump will cavitate like crazy with 750 power. If you have a working 750 engine, it would be easier if you can find a JS750 hull with bad motor. Then, it would be a simple drop in project. Even a 650 hull would be more appropriate than the 440. Just my 2 cents.

 

Thanks. I appreciate your 2 cents. I have a 93 js750. Runs great. Pretty fast. Hate the porpoising. Tried a few things and made it a little better. Found a complete 93 js750 parts ski fairly cheap. Engine needed to be rebuilt but parts is parts. I also have several early 80's 440's and 550's and thought it would make a nice winter project. I already have many of the parts I need. I'm trying to find out the best way to go.
Thanks for your input.

 

By the way, I have a JS800 motor/electronics/pump and am thinking about installing in my X-2 (650). I am worried about the added weight and the hull balanace though.

 

You will have a fast machine!My buddy has a '06 sxr and I was surprised. I thought my twin carbed 750 was fast. I must be getting old. Good luck on the project! I'm still compiling parts for mine. I decided to go with a 550 hull and driveline. I understand that with a 550pump there won't be as much stress on the bulkhead. LOL!

 

If my project works out ok, I think my 800 X-2 will be a fast one, possibly even faster than 800 SXR because of X-2's much lighter hull weight. I'm getting old too for a stand-up. One thing nice about X-2 is that it has a seat for old folks like me!

 

I have most of the parts I need except the exhaust. I know that I have to use a 650 exhaust. Will the stock setup work or will I have to go aftermarket?Thanks.

 

Hi all. I finally put my conversion ski in the water and got most of the bugs out of it. I have to say it was worth every penny and every second of my time. What a rocket! If anyone is is considering doing it go for it.You'll be happy you did!