I have an 82 GMC S-15 with the Isuzu four banger. I'm going to have to repalce the carb for the third time in about 6 months. The truck sat for 4 years before I bought it. It ran when I bought it but it wouldn't idle. I replaced the typical stuff belts and hoses etc.... I had to replace the carb and it lasted about two months. Each time I replaced the fuel filter and put one before the fuel pump. The second time I put on a new fuel pump (mechanical) and new filters. I have not cleaned the gas tank. However the lines look clear and after blowing them out with an air hose I didn't see any contamination. The carb is under warranty so the cost isn't an issue but I would like to drive the truck for more than two months without replacing the carb. It uses a Hitachi carb stock but I think I might try a Weber, any thing to make it run a little better. Also I'm about to junk the air pump. I dont have emissions testing but would this affect how the truck runs.

Thanks for any help
Lon