Been using a clamped d 4-2 and clamped d 6-3 for the last couple of months, and when we do a pump test we never get a consistent reading. So say we are looking for the required 10bar or so, out of five tests we may achieve that only twice, the other three may be 2bar or even 0. As long as i get the 10bar or so a couple of times we will spray and no problems. Just wondered why it fluctuates?? Cheers