I finally got around to removing my leaking injector pump yesterday for an overhaul. I made a discovery (no pun intended) which may save someone some money in the future. On removing the Aircon belt I discovered that the small bypass hose that runs from the thermostat to the 3 way connection near the expansion tank (Sorry rave manual at other house)had been fitted incorrectly to the clamps in the timing cover and had moved forward onto the Air-conditioner belt and rubbed through about 2mm. This may be worth checking. Hope this saves someone