As a newbie I can only post 5 times in 24 hours so have been shut out till now.
The Crankbrothers pump has a dual connection, side by side with nothing that might unscrew, except the tubing to the pump. That is tight. This is the only pump I have right now.
I ordered the screw on presta adapter suggested by smd4. It arrived today and was tested. As soon at the pump head is clamped on it starts leaking. Specifically, when the clamping lever is pulled up it starts leaking. The little screw knob on the presta valve was backed off about halfway, same result. I cannot stop the leaking.
Evidently, when the lever is pulled up to clamp the head onto the presta valve, the mechanism in the head presses down on the top of the presta value that sticks up.
So now order the Lezyne pump and see what happens.
Thank you for your time.