The water level is now right to the top in the 2nd resevoir. The wirring noise did worry me as it did not stop for a few minutes after the engine had been turned off. The engine seems fine, starts and runs smoothly as normal. As I said earlier, I am going to get the mechanic to take another look over.
If only Brickwerks were closer, I wouldn't have the problem of finding a decent mechanic! Although, to be fair this forum is worth it's weight in gold

Thanks again.
Matt