have a 78 350 motor in my tow truck was pulling a car when i threw a alternator belt but still had water pump belt so i kept going but the truck started back fireing like a stuck valve made it to the shop but this morning would not start i thought timeing chain because back fireing like out of time but was not getting gas also took distribator cap off and it turning so I checked my rocker arms and found number 7&8 cylinder intake vales are not moveing so my question is cam wore out and why is it not getting gas and what caused the wear so sudden

 

i have found the cam will wear out fast if the rockers aren't adjusted properly (over adjusted)