1991 Yamaha Outboard Factory Service Manual 9.9 and 15 HP, Page 31Get this manual
3Priming pump and fuel hoses Check the priming pump and fuel hoses for cracks or holes, and replace them, as requiredAlso, check the operation of the check valve by blowing in to it Installation
Always use new gaskets to prevent fuel leakage passed joints To prevent the fuel from leaking passed the fuel hose joints, replace any fatigued fuel hose bands1Fuel meter assembly Place the gasket on the tank, and place the suction pipe, float, and float arm in the tank, and secure them with screws
1Check valve (inlet)
2Check valve (outlet)
-a==fiTID Blow from side Blow from side Blow from side Blow from side