When the engine will not start, or when hard starting or missing indicates a faulty ignition system, proceed as follows:

1. Disconnect spark plug cables from spark plugs. Check condition of plugs and cables. Clean or replace as necessary.

2. Insert a conductive adapter into spark plug cable nipple and establish a 3/16 in. gap between adapter and cylinder head. Turn on ignition and engine stop switches. Crank engine. Check to see if a spark is obtained across the gap. If a spark is obtained, the problem is not in the electronic system or coil. Check carburetion, choke and spark plugs.

3. it no spark is obtained, cneck oattery voltage ana battery connection condition. Turn on ignition and engine stop switches with voltmeter across the battery, and current flowing, voltage should be 11.5 or above. If voltage is low, battery needs charging.

4. Check to make sure that ignition module (on front of frame above the regulator) ground (black lead) is securely fastened to the frame and that the ground wire from the battery to the frame is in good condition. If spark is still not evident, continue with the following voltmeter checks.


Voltmeter should have a resistance of 20,000 ohm/volt or more in order to obtain correct readings.

5. Position rotor so that the center of the sensor is between the two slots.

Connect voltmeter between ignition positive coil terminal (white wires) and engine ground. With ignition and engine stop switches on, the voltmeter reading should equal battery voltage within 0.5 volts. If not, trouble lies in circuit between battery and ignition coil. Check the connections at or in circuit breakers and ignition switch.

6. Disconnect blue wire from coil negative terminal. Connect voltmeter between coil negative terminal and ground. With ignition and engine stop switches on, the voltmeter reading should equal battery voltage. If not, ignition coil primary is defective. Replace coil. Retest for spark after corrections are made.

7. Disconnect sensor plate from ignition module at connector. Connect a voltmeter from pin #1 (red wire) to pin #2 (black wire) of the module connector (Figure 5-23B). With the ignition and engine stop switches on, the voltmeter should read 5.0 ± .5 volts. If not, the computer module is defective and must be replaced.

NOTE: Fabricate jumper cable (Figure 5-23B) to test module and sensor.

CAUTION — When using jumper cable extreme care must be used not to touch exposed wire terminals (6, Figure 5-23B) to each other or ground which could result in damage to ignition module sensor.

8. Reconnect sensor plate using the jumper cable (Figure 5-23B). Recheck voltage from pin #1 to pin #2. Connect the voltmeter from pin #3 to pin #2 to check sensor output. This output should be 5.0 ± .5 volts when the slot is not present at the sensor and should be 0 to 1 volt when the slot is at the sensor. A screwdriver blade can be used to check the sensor output. If these voltages are not present, the sensor plate must be replaced.

1. Pin connectors Part No. 74536-77 (3)

2. Socket connectors Part No. 74539-77 (3)

3. Body receptacle Part No. 72051-77 (1)

5. 18 gauge insulated wire (4 ft.)

6. Wire ring terminals Part No. 9857 (3)

7. Electrical tape

Ignition Module Check
Figure 23-B. Fabricating and Using Jumper Cables

CAUTION — Coil wires must be connected correctly.

Both white wires must be connected to the same coil primary terminal or ignition control module will be permanently damaged.



1. Advance timing mark

2. Retard position of piston top center mark on flywheel

3. Timing inspection hole Figure 5-23C. Timing Marks

DIY Battery Repair

DIY Battery Repair

You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.

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