Randy,

The pressure rise in the high side with increasing OATs is normal.  Rising pressure in the low side is not. 

It sounds like the back pressure circuit is not open to allow expanding fluid in the low side to flow easily back to the reservoir.  A few questions:  What is the pressure in the down side circuit during a gear retraction?  You reported a 0 reading in the low side after takeoff.  Does the pressure bleed back down to zero after retraction or is it zero during the entire retraction sequence.  Also, do you know what vintage your pump is?   

Chris

 

 

 

 

Chris Zavatson

N91CZ

360std