i have a 91 cbr f2 i recently puchesed it overheating on me it full of coolant. i pulled the waterpump cover off and i can spin it by hand?? the oil pump light comes on sometimes too any ideas??

 

Radiator cap.


Start with the simple stuff first.

 

sorry i didnt mention it before i did try a different cap

 

Thermostat?

 

something in your oil pump/water pump has busted. As crazy as it sounds the water pump actually runs off of the oil pump. A chain (inside your motor) runs down from the clutch basket, which is continuously driven by the crankshaft. The chain loops around a sprocket on your oil pump, and the shaft coming out the back of your oil pump drives the water pump shaft and spins that impeller you saw when you took that cover off.