dink 50 125 1 Manuel atelier : Page 37

          1. GENERAL INFORMATION                                                                    DINK 50/125


 ENGINE LACKS POWER

 Inspection/Adjustment                          Symptom                    Probable Cause

 Start engine and                                                         Clogged air cleaner
 accelerate lightly for                                                   Restricted fuel flow
 observation                                                              Clogged fuel line between fuel
                               Engine speed         Engine speed does     tank and carburetor
                               increases            not increase          Clogged exhaust muffler
                                                    sufficiently          Faulty auto bystarter
 Check ignition timing                                                    Split carburetor vacuum piston
 (using a timing light)                                                   diaphragm

                               Correct timing         Incorrect timing    Faulty ignition unit
                                                                          Faulty A.C. generator
 Check valve clearance
                                                                          Improper valve clearance
                                  Correct                  Incorrect      adjustment
                                                                          Worn valve seat (valve stem too
                                                                          protruding
 Test cylinder
 compression
                                                                          Improper valve and seat contact
                                Normal                    Abnormal        Worn cylinder and piston rings
                                compression               compression     Blown cylinder head gasket
                                                                          Flaws in cylinder head
 Check carburetor for                                                     Improper valve timing
 clogging
                               Not Clogged                 Clogged        Clogged carburetor jets

 Remove spark plug and
 inspect
                              Plug not fouled or      Plug fouled or      Fouled spark plug
                              discolored              discolored          Incorrect heat range plug
 Remove oil dipstick and
 check oil level and
 condition                                                                Oil level too high
                               Correct and not            Incorrect or    Oil level too low
                               contaminated               contaminated    Oil not changed
 Remove cylinder head
 oil pipe bolt and
 inspect
                            Valve train             Valve train not       Clogged oil pipe
                            lubricated properly     lubricated properly   Faulty oil pump
                                                                          Insufficient coolant
 Check if engine                                                          Faulty thermostat
 overheats                                                                Worn cylinder and piston rings
                                                                          Mixture too lean
                               Engine does not       Engine overheats     Poor quality fuel
                               overheats                                  Excessive carbon buildup in
                                                                          combustion chamber
                                                                          Ignition timing too early
 Rapidly accelerate or                                                    Air in cooling system
 run at high speed
                                                                          Excessive carbon build-up in
                                                                          combustion chamber
                           Engine does not knock      Engine knocks       Poor quality fuel
                                                                          Clutch slipping
                                                                          Mixture too lean
                                                                           Ignition timing too early


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