The way your pressure jumps around really makes me suspect the tank pipe
restriction problem. Is your pressure gauge on the tank or the line to the
plumbing? If the pump output goes directly to the guage and plumbing, with a
separate pipe to the tank, a restriction in the pipe to the tank could cause the
pressure rise/drop symptoms you described. Is there a valve on the line to the
tank that might not be fully open?


Pressure gage is immediately after pump.
I have a photo of it he
http://i899.photobucket.com/albums/a...ghill/pump.jpg

Here's a video of the same pressure gage as the pump turns on, cycles
through, and stops.
http://www.youtube.com/watch?v=dmI8y-l5aS8

I'm confident that all valves are fully opened.
Any advice or guidance is grealty appreciated!!