1977-2000 Suzuki DT5/6/8 Outboards Service Manual, Page 58Get this manual
FUEL SYS1EM The fuel pump is of diaphragm typeIts diaphragm is forced to deflect inward and outward the cyclic pressure variation inside the crankcase that characterizes two-stroke cycle engineTwo check valves (inlet and outlet) in the valve body to draw fuel in (from fuel tank) through inlet valve and force it out (toward float chamber) through outlet valve according as the diaphragm deflects outward and inwardREASSEMBLY
Il1stall diaphragm set as shown in the figureAfter correctly putting them together, tighten the four screws equally to avoid distortionTransparent plastic diaphragm