Trouble Shooting Guide - Montgomery Ward TMO-3395309 Operating Manual

TROUBLE SHOOTING GUIDE
TROUBLE LOOK FOR REMEDY
Engine will not Battery installed incor- The battery must be installed with the negative terminal, identified at the terminal post by (Neg, N or
crank rectly -), groundecL 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.
Engine cranks
,but will not start
Blown fuse or circuit
breaker
Battery is dead or weak
Mechanical failure
(Wires and switches)
Throttle or choke not in
starting position
No spark to spark plug
Replace fuse with 7-1Y2 amp. automotive type fuse. Fuses seldom fail without a reason. The problem
musl be corrected Check for loose connections in the fuse holder. Replace fuse holder if necessary. A
dead short 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 strands 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 part
Use a hydromete_ to check the condition of the battery. The Specific Gravity (s.g.) should be 1 265 at
80°F. (1.215 s.g. minimum needed for cranking engine). The reason for the battery 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.p,m. A diode {rectifier) is located in the output lead just before the wire harness plug on the
engine side
To Alternator (_ _- -
Shrink 3 AMP DC
Wire Diode Tube (Bart.)
/
._ /'7 AMP AC
pL=__ _==" :-J_'-_ Lf (Lamps)
• - "--5 -- -,
r
Black
Wire Polarized
Plug
The diode changes A.C, to D.C. to charge the battery. A bad diode can either fail to charge the battery
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. D.C.
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) Start the engine The lamp should
light. It it does not, the alternator (stalor) or lead wire is bad and shouid be replaced.
The interlock system includes two mechanical activated switches which are wired in series in the
circuit used to energize the starter solenoid. While testing the interlock system, you will make the
mower temporarily unsafe by permitting 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, tf
the engine cranks, the solenoid is bad. (3) If the engine does not crank when you jump the solenoid,
have the starler motor tested by an authorized engine dealer. If the engine does crank, the problem is
wilh 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.
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 If not, have engine repaired at authorized engine service
dealer.
Faulty spark plug. To test, remove spark plug. Attach spark plug lead to spark plug. Ground the spark
plug body against the engine block. Crank the engine. The spark plug should fire at the electrode.
Replace if it does not.
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