If your engine has a clutch then you need a water pump. Our pump is a manufactured by RMB products, a division of Warehouse Hobbies Inc. and is specific in design for use with gas model boat engines. The pump operates from the negitive and positve pressures generated inside the engines crank case while running. These pressures are feed into the pump by a small tubing connected to a "pulse" fitting on the engine / intake manifold, and then to the "pulse" input on the pump. Once the engine has been started the pump begins to function drawing water from the pick-up source into then through the pump suppling water cooling to the head and or the exhaust manifold an or header. The pulse is strongest when the engine is at a lower idle RPM which is the only time the pump is necessary, as during an idle the clutch is disengauged and the engine soley relys on the water pump to deliver the water cooling. Once the boat is accellorated to speed the water pressure becomes greater than that of the pumps pressure opening the two (2) inner pump valves and bypassing the pumps operations. Once the boat slows to an idle the pump regains its ability to pump cooling water. Our water pump is easy to install and is powered by your engines crank case pulse pressures. This kit includes everything you need to make all connections for both the cooling system and the engines pulse. Instructions are provided to show you how to make all connections. Made in the USA.