Jet Ski

Overview

A jet ski is a personal watercraft propelled not by an external propeller but by a jet pump: an engine drives an impeller that draws water through an intake in the hull bottom and expels it rearward as a high-velocity jet, and steering simply vectors that jet. With no exposed propeller and a planing hull, it can operate in shallow water and turn sharply. This is a high-performance, supercharged three-seater built around a 1,630 cc engine producing over 300 horsepower.

The craft is built on the bonded Hull & Deck, a fiberglass hull capped by a sheet-molding-compound deck. Power comes from the supercharged 4-Stroke 3-Cyl Engine, an inline-three four-stroke fed by the Fuel System and kept cool by an open-loop Cooling Loop that pulls raw water through the running gear. The engine drives the Jet Propulsion Pump through a direct shaft. The rider steers and throttles from the Handlebar Controls at the handlebar, sits on the molded Seat, and the 12V Electrical System system manages ignition, the ECU and starting.

How it works

The four-stroke engine breathes through a centrifugal supercharger that crams extra air into the cylinders, raising power well above a naturally aspirated unit of the same size. Electronic fuel injection meters fuel to each cylinder, and the ECU controls spark and injection timing. The crankshaft couples directly to the jet pump's drive shaft, spinning a stainless impeller inside the pump housing. Water enters through the hull intake grate, is accelerated by the impeller, straightened by stator vanes, and forced out the steering nozzle as thrust. Turning the handlebar swivels that nozzle to vector the jet, while a reverse bucket can drop over the jet stream to redirect thrust forward for braking and backing. Because steering authority depends on jet flow, the craft turns best under throttle. Cooling water tapped from the pump circulates through the engine and water-jacketed exhaust before discharging overboard.