Hi, i have a 16hp 180deg opposed twin briggs.
At one stage i had to put choke on 1/4 for the moewer to run, pulled the carb apart and cleaned it as best i could. Didn't make any diff. Anyway, i pulled the pump off and there was NO SPRING in there and the remnants of the metal spring washer(they were rusted away), i have no idea how it was working but after that things went down hill, i swapped pump parts with another motor, i then had to run full choke, it would die, drop choke off and it was ok, then full choke again etc etc, seems to idle fine but when it gets up in revvs it starves then give it choke and a few seconds later it floods, that's what it seems like. doesn't backfire or anything. So then i bought a carb kit and some carb cleaner, sprayed it everywhere (except on perishables) put new parts in and NO DIFFERENCE!!!! GRRRRRR. Anyway, i ended up overtightening the bloody manifold bolts and busted it and the spacer as well. I won't be doing THAT again. I think i will clean out the fuel tank and change the back half of fuel line next. i have already done the filter and front half of fuel line and done the vacuum hose to fuel pump. How would the fuel pump spring and assoicated parts rust? i presume water from the fuel supply? not sure. any help appreciated.