I always got a bubble in my copper lined oil pressure guage. What the trick in keeping it out? I knew it had a bubble in it because when I would bleed it at the gauge (plastic line too..was visible changed to hard line with same results, just crack the line for a second with a napkin to catch the oil) the gauge would show a small vibration at idle. Before bleeding, it would be 3 psi lower and not vibrate. Bad guage?
