Thanks Dabnis for your helpful advice and support.
I found a leak in the Racor MD12 filter at the o-ring between the filter and the water separator. On inspection it looked fine, it was brand new, but unscrewing, cleaning and re-tightening a little more snugly did the trick.
Rather then purchase an electric pump I closed the fuel line at the tank and blew into the end of the fuel line. The leak was obvious! I also figured out that the primer on the lift pump only works when the pump is in compression- not made clear in the manual. I did not feel comfortable with my reassembly and the primer mechanism appeared to slip past the diaphragm tab on occasion, so I changed out the lift pump. All is good.
You are welcome, thanks for the feedback, one can always learn from others. glad it worked out. You must have good lungs to get enough pressure for the leak to show!!