Bolens MTD7122B09 manual ToAlternator~~~ --~-- I s, Red, Black WirePolarized, Plug

TROUBLE SHOOTING CHART FOR ELECTRIC START MODELS

TROUBLE

Engine will not crank

LOOK FOR

Battery installed Incor. rectly

Blown fuse or CirCUli breaker

Battery is dead or weak

-REMEDY----:J

The battery must be instatled with the negative terminal, identified at t'le terminal post by (Neg. N or -). grounded The positive terminal (Pos, P or ..) attaches to the large cable from the solenOid The small red wire from the fuse holder or cirCUit breaker IS also attached to the positive termInal

Replace fuse with 7'/2amp fuse 'I. x 1'1." Ig CircUit breaker WIll reset Itself when it cools off Fuses or circuit breakers seldom open or fail without a reason The problem must be corrected Check for loose connections In the fuse holder Replace fuse holder if necessary A dead shon may be In the cranking or charging Circuit where the Insulation may have rubbed through and exposed the bare wire Replace the wIre or repair with electrician's tape if the wire strancs have not been damaged Note: Look for a wire pinched between body panels. burned by the exhaust pipe or muffler or rubbed

against a movIng panI

Use a hydrometer to check the condition of 1he battery The SpecIfic GravIty (sg) should be 1 265 at 80°F (1.215 sg minimum needed for cranking engine) 'he reason for the batter,. failing must be determined (1) Defective battery Battery will not accept or hold a full charge (2) Short circuIt.

Check for grounded wire (3) Charging system not working

The charging system IS an alternator located under the flywheel It IS unregulated and rated 3 amp at 3600 r.pm A diode (rectifier) IS located In the output lead just befort! the wIre harness plug on the engine side

Red

Wire Diode

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ToAlternator<)~~~ --~--' I s

t,:.;';';;;;"D._~

Black

WirePolarized

Plug

The diode changes AC to DC to charge the battery A bad diode can either fall to charge the bat. tery or discharge the battery If the alternator IS shorted as well as the diode To test: (1) Disconnect charger lead from the battery (small red wire) (2) Connect 12 V small test lamp between the 3 amp DC charge lead and the positive terminal of the battery. (3) With the engine off, the lamp should not lIght If It does. the diode and possibly the alternator should be replaced (4) Stan the engine The lamp should light. If it does not, the alternator (stator) or lead wIre IS bad and should be replaced

Mechanical failure The interlock system Includes two mechanical activated switches which are wired in series in the

(Wires and swItches) circuit used to energize the starter solenoid While testing the InterlocK system, you will make the mower temporarily unsafe by permit1ing the engine to be started wIth the blade and clutch engaged WARNING While testing, disengage the clutch, shut off the blade control, set the parking brake and place the gear shift lever in neutral. Attach a wire (minimum 18 gauge) to the positive terminal of the battery and touch the other end to the small terminal on the solenoid If the engine does not crank: (1) There is a loose connection or poor ground (2) The solenoid may be bad The solenoid can be checked by using a heavy wire (*8 gauge minimum) and Jumping between the two large terminals If the engine cranks, the solenoid is bad. (3) If the engine does not crank when you jump the solenoid, have the starter motor tested by an authorized engine dealer If the engine does crank. the problem is with one of the safety switches. Ignition switch or the wire between the fuse holder (or circuit breaker) and the small terminal on the solenoid. Note: Look for a poor connection at the switches or a defective swItch Replace if necessary

Engine cranks but will nol star1

.,

Throttle or choke not in

starting poSition

No spark to spark plug

Check owner's guide for correct position for throttle control and choke for starting

Spark plug lead disconnected Connect lead Hold spark plug lead away from engine block about 1/8" Crank engine. There should be a spark II not. have engine repaired at local Western Auto Ser- vice Center.

Faulty spark plug To test. remove spark plug. Attach spark plug lead to sparl\ plug. Ground the spark plug body against the engine block. Crank the engine. The spark plug should fire at the electrode.

I Replace il it does not J

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