Review on ACDelco GM Original Equipment 251-780 Engine Water Pump: Durable and Reliable Automotive Essential by Christopher Wiggins

Perfect fit, 100% OEM. High quality product, complete with screws, rubber seal, thermostat and all necessary small parts. Easy installation. Remove the coolant bypass (metal pipe). Remove the thermostat, unscrew the 3 screws 13mm on the cylinder block. First I would use a 1/2 inch screwdriver to pry up the tensioner and remove the belt from the pulley. Then unscrew 3 screws from the block. Be sure to clean the sealing areas. I didn't need one on the block, one on the thermostat bypass (metal seal not included), the old one was perfect. A semi experienced person could probably do it in 4 hours with the right tools.