just wanted to say that I had the turbine running again and with absolute no problems at all.

I can't see any air bubbles at all and the only thing I changed was the screw in the filler line.

Nevertheless I am taking on board all the advice and will replace the tie wraps although I can pull very hard without the tubes to come off. (and I mean I can pull very hard)

With regards to the shut off valve.
As I mentioned before I was consulting several forums and people are having lively discussions of where to put the valve.
I don't like the valve to be on the pressure side of the pump. If I shut that valve will the pump not create a high pressure on the tubes?

Finally, what is wrong with a Festo valve? Why should a JetCat valve be better?

Thanks again for all the help and advice. I am really enjoying my new venture into turbines a lot.

Ulrich