Selective reciprocating element disablement in a pump

A method of operating a pump system comprising:

• operating a power source to reciprocate reciprocating elements in respective bores in a body of a fluid end by reciprocating push rods coupled to respective reciprocating elements to move in a forward direction in a forward stroke and in a return direction in a return stroke;
• identifying at least one reciprocating element for decoupling from a respective push rod;
• retaining the identified reciprocating element from movement in the return direction by engaging a retainer with an engagement profile of the identified reciprocating element;
• selectively decoupling the identified reciprocating element from the respective push rod;
• and
• continuing to operate the power source to reciprocate the reciprocating elements that remain coupled to respective push rods.

A fluid end for a pump system comprising a power source operable to reciprocate push rods, the fluid end comprising:

• bores in a body;
• and
• reciprocating elements configured to be reciprocated within respective bores by being releasably coupled to respective push rods to move in a forward direction in a forward stroke and in a return direction in a return stroke, each reciprocating element comprising an engagement profile,
• wherein each reciprocating element is configured to be prevented from moving in the return direction and decoupled from a respective push rod independently of the other reciprocating elements.