A selectable detent relief valve of this invention is used to operate a hydraulic
detent mechanism on a manually operated spool valve. This design has three modes
of operation, no-detent, continuous detent and kick-out detent. The no-detent position
allows flow to pass through the relief valve, from a first port to a second port
and bypass the relief function. The pressure created, disengages the detent mechanism
in the spool valve. The spool always returns to neutral position as long as pressure
is present. The continuous detent position blocks the flow from a first port to
a second port. The kick-out detent position allows flow to pass from the first
port to the second port to override (kick-out) the detent mechanism in the spool
when the pressure is greater than 2600 psi.