WATER PUMP A-SERIES (NO BY PASS) 3 YEAR GUARANTEE

3 YEAR GUARANTEE-UK made.Large impeller higher capacity water pump. produced as original Rover Airtex tooling has been scrapped.
Fitted with a PPS, glass filled plastic impeller as used by Jaguar and Aston Martin it reduces weight on the bearing loading and a triple lip seal giving a better controlled flow rate through the rev range.
The pump is about 130 gramms lighter and uses the rolled edge gasket facing evolved by rover for better sealing.
These pumps have the same aluminium housing and the same deep impeller as the standard items, the only difference is that the bypass adapter has been deletede.
This means that if you are running without a bypass hose you don't need to plug it, therefore one less possible leak.
It's warmer overseas than in the UK. This higher capacity water pump moves more coolant than the small impeller GWP132.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 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.