The Walbro carb on the Multitrim 16 does not have a pump as such but relies on fuel delivery from the vacuum formed when the piston sucks fuel through the carburettor. The probable cause is the diaphram under the cover plate with four screws. A replacement kit costs a few £/$. Take off the carb to verify the carb number which should be stamped into the body. Get a carb rebuild kit on line or from your local dealer.
Bertiebrooke
May 2010
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