I'm told that it is common to go thru a couple of clogs with a rebiult set of dells if they sat for any legth of time. Too many places that you can't get to when they are cleaned. My car didn't sit before I put this engine in but I had 3 clogs so far, Kevin had 3-4 clogs in the begining and Joe (Yetibone) went thru a few with Sue's car too. I have a filter before the CB fuel pump and just before the engine. It's not to hard to clear them, just drive it and get thru the "clean out period".