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Winter Project Seadoo 720 Build


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I've started collecting engine parts from Ebay to build a replacement engine for my Challenger. The PO threw in a WSM crank rebuild kit and a WSM Platinum piston kit when I bought the boat. I plan on installing a WSM rotary shaft since my engines are leaking from the shaft seals. Both motors have new carbs already. I've read up on performance mods (Group K) and Mr. Bill and aside from port matching all intake and exhaust surfaces I'm likely to have Group K mill the heads and call it good. Since my pumps have stock impellers I think upgrading to Solas props will give me better performance w/o affecting reliability. The PO did liners and pump rebuilds 2 years ago. Does this sound like a good plan or is there something I'm missing ? All rubber hoses are being changed out now and I'm replacing the starter cables also since they're corroded...