STARTERS Troubleshooting and Identification/Index Fig. 46 - Typical 12 VDC Starter Motor Fig.  47 - Typical 120VAC Starter Motor TROUBLESHOOTING 12 VOLT & 120 VOLT STARTING SYSTEMS The following list is given to aid in diagnosing problems for 12 volt and 120 volt systems. NOTE: If a starting problem is encountered, the engine itself should be thoroughly checked to eliminate it as the cause of starting difficulty.  It is a good practice to check the engine for freedom of rotation by removing the spark plug and turning the crankshaft over by hand, to be sure it rotates freely. 1.  Cranks Engine Slowly - A. Additional load affecting performance (see note). B. Discharged battery (page 11 and 17). C. Faulty electrical connection (battery circuit). D. Discharged battery (see alternators). E. Dirty or worn starter motor commutator, bearing, weak magnets, etc. F. Worn brushes or weak brush spring. G. Wrong oil viscosity for temperature expected. H. Extension cord longer than 25 feet.  (120 volt AC only) Motor Identification Manufacturer Name (Fig.  46 and 47) Motor Voltage Page Number Briggs & Stratton 3-1/16" L 12 23 Briggs & Stratton 3-3/4" L 12 23 Briggs & Stratton 3-1/2" L 120 23 American Bosch SMH-12-A11 12 30 American Bosch SME-12-48 12 30 American Bosch 01965-23-MO-30-SM 12 30 American Bosch SME-110-C3 120 30 American Bosch SME-110-C6 120 30 American Bosch SME-110-C8 120 30 American Bosch 06026-28-M030SM 120 30 Mitsubishi MMO-5ML 12 30 Mitsubishi MMO-4FL 12 30 Mitsubishi M001T02271 12 30 Mitsubishi V282188 120 30 Motor Products None 12 10 Fig.  48 - Starter Motor Identification 9