preferably includes wiper seals for sealing the pumping chamber 40 any weeping past the wiper seals goes into the wash chamber 16 where the detergent is destined to go anyway the plunger is spring loaded and is normally extended all the way into the pumping chamber energizing the solenoid 26 causes the plunger to retract drawing liquid from the batch chamber 36 to the pumping chamber 40 through the pumping chamber inlet port 44 de energizing the solenoid actuator 26 causes the spring to relax extending the plunger 42 and thus dispensing detergent from the pumping chamber 40 through the pumping chamber outlet port 46 advantageously large passages and short flow paths are employed to permit free movement of thick gel detergent now with reference particularly to fig7 a 7 b and 7 c an umbrella check valve 48 is preferably employed in each of the pumping chamber inlet and outlet ports 44 46 respectively valve seats 50 for each of the said inlet and outlet ports are shown in fig7 b umbrella check valves are preferred because they comprise soft elastomers that move easily and have low stress as shown in fig7 a an extended piece 52 is employed to pull the valve through the mounting hole this piece 52 is designed to break off after pull through.