UK made. Large impeller higher capacity water pump with top quality die cast body .
This higher capacity water pump with larger impeller moves more coolant than the small impeller GWP132 (for 850/997 blocks). See GWP134 for pump with by-pass hose take off, GWP187 is without take off. The impeller sticks into the block very slightly more than 1/2". This water pump will fit all 1275cc blocks and most 998/1098 from 1969 on and with some work on early blocks it can be made to fit an early small bore block.
Use of a high capacity water pump helps to reduce cavitation in the water jacket, particularly at high RPM, as well as circulating a greater volume of coolant. Further reduction of cavitation is achieved by using a large diameter water pump pulley CAM6408 as originally fitted to the Cooper S and reintroduced on the A-Plus engines. It is necessary to check clearance between the large pulley and the head, if a lot of material has been machined from the head face it may foul the pulley. Small bore engines with 12G940 cylinder heads can't use CAM6408 and it is necessary to modify the top edge of the high capacity water pump or the 12G940 head will rest on the pump and not seal properly, modify for at least 1/16" gap.
Use SH605101 x2 and BH605151 x2 bolts.