|
Randy,
The next thought experiment might by to ask whether or not
your (and Lorn's) spool valve is returning to center for some reason after pump
shut down. That would allow pressure to build in the low and high sides
simultaneously. Generally it takes quite a bit of force to move the spool
valve around. The O-ring provides a lot of friction. Two things are
obvious though. First, the valve is working properly while the pump is
running since you (and Lorn again) see zero pressure on the low side. The
second constant is that when the pump is not running and actively pushing the
spool valve against the poppet valve, your systems are sealing themselves
up. If your spool valve had very little or no friction I could
see this happening. The poppet valve does have a very light
spring to help close it when not subjected to any other
forces.
This video was posted previously. It shows the system
responding to an intentional leak from high to low. The pump cycles
repeatedly without affecting the low side pressure reading.
Randy, the answer is out
there........somewhere.
Chris
|