In order the get a non leaking reading you need to test without any baskets inside the portafilter

thanks - that was what i was wondering. i'll check it out later today.

cheers!

well... a good wrapping of the gauge threads with teflon tape, then a test with no basket and - NO Leaks! I'm getting about 12 bars, so the next thing to do is install the new adjustable OPV, dial the pressure back a bit and then... who knows. Thanks to all who chimed in.

steve

I have heard that to get a good reading from a vibratory pump machine you should use a fluid-filled gauge -- it dampens the momentary changes and vibrations. There's no need for that on a rotary vane pump machine -- the internal adjustable bypass valve maintains a more stable constant output pressure.

One other thought to pass on. Some portafilters have slots cut into the rim at the top (I am guessing to prevent a clogged output port from causing pressure build-up in the portafilter) -- I can't recall which brand it was. I have also seen a portafilter (made for a Bezzera bz02) that has a small hole drilled high up on the side (probably for the same reason as the slots cut into the top rim of the other portafilter). Neither of these portafilters will work for pressure testing.

I know this is an old thread -- but I hope this helps someone dealing with this issue....

Philip