If you can hear the motor it's usually a broken pipe where it goes through to the boot lid. There's a good thread on here somewhere that shows where the pipes run.
The motor works just fine. I am assuming that the water comes from the bottle that's under the bonnet (I've had other cars where there was another bottle in the boot). If it was a broken pipe, wouldn't there be a pool of water somewhere? As of yet, I haven't found one. At this time, I'm thinking that the nozzles are blocked. I have one blocked nozzle on the front jets, so I'm swopping them out for a pair of jets from a Citroen Xsara. The rear jet appears to be moulded into some sort of cover. How that comes apart, I've no idea.
It's strange really. As the years have rolled by. Cars have become more complex and owner input has declined. Owner input has declined simply because the cars have become more complex. The easiest car to work on I've ever had, was a Triumph Herald. I even managed to change the pistons without taking the block out of the car, or removing the cylinder head (Sump plate off, unbolt, swing crank aside and pull on the con rod). Everything was in plain sight and easy to get at. Today, it's pipes and plastic bits everywhere! Electronic gizmos don't help either. I went looking for the distributor, only to find I didn't have one! Is it any wonder then that owner input has declined? Having said that. The life span of modern cars has been extended for a considerable amount of time.
In days of yore. People who bought a 2nd car looked at the mileage first. Back then. A car that could go 'around the clock' was almost unheard of. Now it's an every day occurrence. My 25 has done 94000. It's solid enough to do that again. If I compared the Rover to a car that was built in the 1970's. The condition would suggest that it was about 5 years old. Not the 13 years it actually is. Such is the improvement in materials and build quality. But that's the rub isn't it? It's almost as if the owners input has been designed out of the equation. Once the little faults begin to stack up. The car gets sold off. Sad really. These little faults are so easy to fix.
I only bought the 25 as a stop gap until the right 75 'Connie' comes along. Having said that. the 25 isn't going anywhere until it's right!