Water Pump: Description and Operation

The coolant pump is fitted between the two cylinder banks, on the front face of the cylinder block.
The pump consists of a housing containing a shaft, with a shrouded plastic impeller on one end and a drive pulley on the other.
A pair of roller bearings support the shaft in the housing. A seal behind the impeller prevents coolant from contaminating the bearings. Should this seal fail, coolant escapes from a witness hole in the housing indicating that immediate action is required.
An O-ring and an aluminum-alloy gasket, seal the ports between the pump and the cylinder banks.