Thanks for the label file Del, it works as you say.
I drained the whole thing down. It went much lower than it sinks to naturally through the leak, all 4 tyres hidden in the wheelarch. Then inflated the accumulator up to about 15 BAR (It took 8 runs to do this) and the compressor got to 97˚C so I allowed it to cool for a minute or two between runs. I wonder how many runs it should take? It seems to run for a prescribed amount of time each time. Last night I inflated the accumulator and the front axle to max and will check it in a bit so see what the pressures are.
I also will fit the new valve block this afternoon in any case as it is an early 08 part with 111,000 miles and mine is late 05 with 271,000miles. We are now pretty much at the stage where all used parts are >10 years old on the D3
