Ok, I finally fixed my boat (and boy do I feel stupid!) I isolated that fuel filter housing, I insulated the fuel pipes with some heat reflective sleeving from the napa store (and it looks pretty on my new engine) and although I change that remote filter every season, I have not replaced the carb filter. When I rebuilt the carb (as a GM tech I think this would be about my 2000th quadrajet overhaul, one more reason I wasn't buying into missing something) I figured i would go back to the fuel filter without the check valve (I put one in with the check valve to help alleviate the carb drying out after sitting a week-it didn't work anyway) weelll....... after I cut that filter open and found all the dirt packed inside.... well we went for another ride! I guess the dirt would pack itself in after a cruise and really silt into the filter at idlem and well, not flow very well. Whay a dumby. well capt., I guess I can kiss that 6 gal per hour goodbye, but my '78 catalina express 254 sure does run sweet now. Thank you all for putting up with me..