Suzuki outboard motors 1988 2003 repair manual., Page 70Get this manual
4-8 FUEL SYSTEM 1Gather as much information as you can2Duplicate the conditionTake the boat out and verify the complaint3If the problem cannot be duplicated, you cannot fix itThis could be product operation problem4Once the problem has been duplicated, you can begin troubleshootingGive the entire unit careful visual inspectionYou can tell lot about the engine from the care and condition of the entire rigWhat's the condition of the propeller and the lower unit? Remove the hood and look for any visible signs of failureAre there any signs of head gasket leakageIs the engine paint discolored from high temperature or are there any holes or cracks in the engine block? Perform compression and leak down testWhile cranking the engine during the compression test, listen for any abnormal soundsIf the engine passes these simple tests we can assume that the mechanical condition of the engine is goodAll other engine mechanical inspection would be too time consuming at this point5Your next step is to isolate the fuel system into two sub-systemsSeparate the fuel delivery components from the carburetorsTo do this, substitute the boat's fuel supply with known good supplyUse gallon portable tank and fuel lineConnect the portable fuel supply directly to the engine fuel pump, bypassing the boat fuel delivery systemNow test the engineIf the problem is no longer present, you know where to lookIf the problem is still present, further troubleshooting is required6When testing the engine, observe the throttle position when the problem occursThis will help you pinpoint the circuit that is malfunctioningCarburetor troubleshooting and repair is very demandingYou must pay close attention to the location, position and sometimes the numbering on each part removedThe ability to identify circuit by the operating RPM it affects is importantOften your best troubleshooting tool is can of cleanerThis can be used to trace those mystery circuits and find that last speck of dirtBe careful and wear safety glasses when using this methodFig20 The use of an approved fuel additive, such as this Suzuki Fuel Conditioner and Stabilizer, will prevent fuel from souring for up to twelve months
COMMON PROBLEMS
Fuel Delivery
ISee Figure 9