grand dink 125 mmc 1 Manuale-dofficina : Pagina 21

          1. GENERAL INFORMATION                                                       GRAND DINK 125/150



 TROUBLESHOOTING

 ENGINE WILL NOT START OR IS HARD TO START


 Inspection/Adjustment                         Symptom                 Probable Cause

 Check if fuel reaches
 carburetor by loosening
 drain screw                                                           Empty fuel tank
                                                                       Clogged carburetor fuel inlet
                                                                       tube, vacuum tube or fuel tube
                                                                       Clogged auto fuel valve
                                Fuel reaches        Fuel does not      Clogged float oil passage
                                carburetor          reach carburetor   Clogged fuel tank cap
                                                                       breather hole
                                                                       Clogged fuel strainer
 Remove spark plug and                                                 Clogged fuel filter
 install it into spark plug                                            Faulty fuel pump
 cap to test spark by
 connecting it to engine                                               Faulty spark plug
 ground                                                                Fouled spark plug
                                                                       Faulty CDI unit
                               Spark jumps         Weak or no spark    Faulty A.C. generator
                                                                       Broken or shorted ignition coil
                                                                       Broken or shorted exciter coil
                                                                       Faulty ignition switch

 Test cylinder                                                         Starter motor idles but
 compression                                                           crankshaft does not rotate
                                                                       Valve clearance too small
                                                                       Improper valve and seat contact
                                Normal                   Low or no     Worn cylinder and piston rings
                                compression              compression   Blown cylinder head gasket
                                                                       Flaws in cylinder head
                                                                       Seized valve
                                                                       Improper valve timing
 Start engine by follow-
 ing normal starting
 procedure
                                                                       Faulty auto bystarter
                              Engine does not       Engine fires but   Air leaking through intake
                              fire                  does not start     pipe
                                                                       Incorrect ignition timing
                                                                       Incorrectly adjusted pilot screw


 Remove spark plug and
 inspect again

                                                                       Flooded carburetor
                               Dry spark plug        Wet spark plug    Faulty auto bystarter
                                                                       Throttle valve excessively
                                                                       open




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