There are several synonyms for the phrase "prime the pump" which means to stimulate or encourage a situation or process. One possible replacement is "kick-start," which implies an initial push to get something going. Another term is "jumpstart," emphasizing the need for a sudden jolt of energy or action. "Lubricate the wheels" can also be used to indicate the need for smooth functioning. Similarly, "grease the wheels" means to make things easier or more efficient. "Fan the flames" is another idiom that can replace "prime the pump," referring to the act of adding fuel to a fire to keep it burning strongly.