I am having the same problems with after market replacements as well. My Airtex #4149 (made in Illinois 20 years ago) was leaking fuel. I ordered a replacement from a specialty vendor (same model but made in Mexico?) and it quit on me about 10 miles from home. Ordered another from NAPA and the truck is running but there is not a continuous flow, it seems to come in spurts, sometimes leaving the filter before the carb empty. Gonna have to look at a rebuild kit from Then and Now
