From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Troubleshooting chart for locating automobile starting and lighting faults.
| Identifier | ExFiles\Box 61\2\ scan0184 | |
| Date | 21th April 1921 guessed | |
| X. 3374 Chart for Locating Automobile Starting and Lighting Troubles STARTING MOTOR TROUBLES Test Procedure Case I—Starting motor shows no life whatever. 1. Turn on the lights and try starter. If lights do not dim, look for (a) An open circuit in (1) The starting switch (2) The motor terminals (3) Ground connection to frame of car (if ground return system) (b) Dirty or glazed commutator. 2. Remove and examine brushes carefully. (a) Brushes worn out (b) Brushes not bearing on commutator (c) Brush material of too high resistance. 3. If the ammeter shows no reading when lights are switched on, if the starting motor kicks over spasmodically or not at all, or if the lights do or do not dim when the starting button is depressed, examine for short circuit in (a) Internal motor circuit (1) Field or armature coils (2) Check for open circuit in armature where coils are soldered to commutator segments (b) External motor circuit (1) To frame (2) In defective starting switch. 4. If ammeter needle flickers examine for “swinging” short circuit. Case II—Starting motor shows some life but not enough to turn the engine over. 1. Turn engine over by hand. If this is impossible look for engine trouble. (a) Bad engine bearings, especially if the bearings are of the smooth type. (b) New bearings not worn in. (c) Bendix drive stuck in fly wheel. 2. If engine is free, look for (a) Poor contact at battery terminals (b) High resistance contact at brushes (c) Poor connection between brush and shunt (d) Poor connection between shunt and brush holder. (e) All brushes not bearing on commutator. (f) Brushes stuck in brush holder. (g) Grounded brush holder. (h) Loose ground connection (if ground return system). (i) Battery below cranking capacity (j) Open circuit in armature coils. 3. Disconnect battery and make a temporary connection to a fully charged storage battery. If the starting motor will then turn the engine over, the battery in the car is at fault. 4. Test storage battery with hydrometer. If the storage battery is low look at the generator. (Note—Always make hydrometer reading before adding distilled water.) 5. If battery is low or lights are dim test out ampere charging rate of generator. (Do not rely upon ammeter on car.) Case III—Lights and spark are cut off entirely when starting switch is depressed. 1. Examine for short circuit in (a) Starting switch. (b) Motor wiring (c) Motor itself. Procedure if Generator is at Fault 1. Test for open circuit in (a) Generator terminals. (b) Battery connection. (c) Ground connection to car frame (if grounded return system). (d) Fuse. (e) “Cut out” or magneto switch. 2. Test for short circuit in (a) Generator itself. (b) In wiring. 3. Examine brushes for (a) Pitted or burned faces. (b) Dirty or glazed commutator. (c) High resistance contact at brushes. (d) Worn out brushes. (e) Poor connections. (f) Brushes not bearing on commutator (faulty spring or holder). 4. Examine generator for (a) Worn bearings causing unequal air-gap. (b) Reversed polarity (storage battery is sometimes reversed in position in car). 5. Examine regulator and cut-out relay for (a) Dirty contact. (b) Contacts out of adjustment. (c) Regulator cuts out too soon or not soon enough, due to gummed mechanical parts. (d) If third brush regulation, see brush connection or look for defective mechanism. Specify PYRAMID BRUSHES for Automobile Starting Motors and Lighting Generators. | ||