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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>David, Hank…..thank you for help and advice. Hank you were just about on the money.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>You’ll recall that my OD was slipping in & out at low revs? Of course you do.<o:p></o:p></p><p class=MsoNormal>I bought a gauge from ODSpares, excellent people/very helpful. (In retrospect, I wonder how I’ve managed for so long without one).<o:p></o:p></p><p class=MsoNormal>Pressure showed as well into the 470 to 490 range whilst OD was engaged at +/- 1,500 rpm in 4<sup>th</sup>. Which is GOOD.<o:p></o:p></p><p class=MsoNormal>But, pressure dropped to zero immediately upon disengaging and switching off. Which is BAD.<o:p></o:p></p><p class=MsoNormal>The little hole in the so-called “Valve operating” was/is clear.<o:p></o:p></p><p class=MsoNormal>I phoned Dave Twigger at ODSpares who said that there was debris under the ball on the seat there OR, if it was clear, then the ball needed reseating.<o:p></o:p></p><p class=MsoNormal>So, I gave the ball a few brisk taps and the pressure drop did slow a little up on the next gauge test.<o:p></o:p></p><p class=MsoNormal>I gave it some more taps and it improved somewhat again. Now takes about 30 seconds to get down to, say, 20psi and then loses pressure quite slowly.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>So:-<o:p></o:p></p><ol style='margin-top:0cm' start=1 type=1><li class=MsoListParagraph style='margin-left:0cm;mso-list:l0 level1 lfo1'>How hard can one “Tap” the ball? Not the easiest question to answer, I do appreciate that. One man’s tap is another man’s wallop?<o:p></o:p></li></ol><p class=MsoListParagraph>I suspect I’ll have to repeat the process……<o:p></o:p></p><ol style='margin-top:0cm' start=2 type=1><li class=MsoListParagraph style='margin-left:0cm;mso-list:l0 level1 lfo1'>What time duration is acceptable in operating terms for the pressure drop? What am I aiming at?<o:p></o:p></li></ol><p class=MsoNormal style='margin-left:18.0pt'><o:p> </o:p></p><p class=MsoNormal style='margin-left:18.0pt'>Thanks, Simon<o:p></o:p></p></div></body></html>