i see... i have a 3 cylinder 2 stroke. it has a pulser straight at the back of the pump which seems to be lined up with the bottom cylinder and another pulser coming in at the front of the pump via a hose that's lined up with the middle cylinder. If i pinch/block this hose it still works pretty good? somtimes theres a little fuel in there (i've installed a clear hose). would you say this is normal?Motors use crankcase compression to move fuel.----Some pumps use a pressure pulse from one cylinder / crankcase.----Other designs use PRESSURE from 2 crankcases.-----A 4 cylinder 2 stroke has 4 separate crankcases.