2 is provided at the system inlet 11 in order to disrupt flow to the self cleaning pre filter system 10 as well as to isolate the pre filter system 10 from its fluid source during cleaning of the sediment filter 13 finally a normally closed solenoid controlled drain valve v 3 is provided in the drain port 18 of the filter bowl 17 for evacuation of detritus from the self cleaning pre filter system 10 because as will be better understood further herein it is desirable to fully and completely open the drain port 18 with minimal fluid resistance it is important in implementation of the present invention that the solenoid controlled drain valve v 3 be of a large volume capacity to this end applicant has found that the series 1000 solenoid piloted one inch port electric control valve commercially available from evolutionary concepts inc of san dimas calif under the trademark u201c eci u201d is suitable for use in the present invention as also will be better understood further herein each solenoid actuated control valve v 1 v 2 and v 3 is in electrical communication with a controller 33 as will be readily appreciated by those of ordinary skill in the art such a controller may comprise a simple state machine or may be microprocessor based as will depend upon the greater application with which the self cleaning pre filter system 10 of the present invention is utilized referring now to fig4 a timer based control scheme 37 for operation of the present invention is now detailed under such a timer based control scheme 37 upon starting 38 of filtering operation a counter is set equal to a pre determinable.