I have a 4 OHP Quattro Briggs & Stratton engine on my lawnmower, and
when I use the prime bulb to try to get the engine started the priming
doesn't work. I take off the top of the sort of rectangular metal box
that holds the filter, (and the filter appears to be clean), and pour
a little gasoline into the engine and the engine starts up. Can
someone tell me how to get the prime system working again? Thanks,

JD