| Page 23 - Index - Page 25 |
| Four Cylinder Engines
1978-1997
Four Cylinder Engines Using a Single Switch Box and Four Ignition Coils
|
No Fire At All:
- Disconnect the black/yellow kill wire AT THE PACK and retest. If the engine’s ignition fires now, the kill circuit has a fault-possibly the keyswitch, harness or shift switch.
- Disconnect the yellow wires from the stator to the rectifier and retest. If the engine fires, replace the rectifier.
- Check the cranking RPM. A cranking speed less than 250-RPM will not allow the system to fire properly.
- Check the stator resistance and DVA output as given below:
|
| Motors with Flex-plate Flywheel |
| |
Wire |
Read To |
Resistance |
DVA |
|
| |
Blue
Red/White
|
Blue/White
Engine Gnd |
5000-7000
125-155 |
180V or more
25V or more |
|
Motors with Cast, Vented Flywheel |
| |
Wire |
Read To |
Resistance |
DVA |
|
| |
Blue
Red
|
Blue/White
Red/White |
3250-3650
75-90 |
180V or more
25V or more |
|
Motors with Red Stator
|
| |
Wire |
Read To |
Resistance |
DVA |
|
| |
White/Green |
Green/White |
500-700 |
180V or more |
|
Red Stator Adapter
|
| |
Wire |
Read To |
Resistance |
DVA |
|
| |
Blue
Blue (each) |
Blue
Engine GND |
Open
Open |
180V or more
180V or more |
|
No fire or Intermittent on One or More Cylinders:
- If the cylinders are only acting up above an idle, connect an inductive Tachometer to all cylinders and try to isolate the problem cylinders.
- Check the trigger resistance and DVA output as given below:
|
| |
Wire |
Read To |
Resistance |
DVA |
|
| |
Purple wire(#1)
Brown wire(#3)
Purple wire(#1)
White wire(#2)
Brown wire(#3)
White/Black wire(#4) |
White (#2)
White/black (#4)
Engine GND
Engine GND
Engine GND
Engine GND |
800-1400
800-1400
Open
Open
Open
Open |
4V or more connected
4V or more connected
1V or more(a)
1V or more(a)
1V or more(a)
1V or more(a) |
|
(a) This reading can be used to determine if a pack has a problem in the triggering circuit. For instance, if you have no fire on one cylinder and the DVA trigger reading for that cylinder is low – disconnect the trigger wire and recheck the DVA output to ground from the trigger wire. If the reading stays low – the trigger is bad.
Note: If #1 and #2 or #3 and #4 are acting up, check the trigger as described above. The trigger has two coils firing
four cylinders. #1 & 2 share a trigger coil and #3 & 4 share a trigger coil. Also, the switch box is divided into two
parts. The #1 and #2 cylinders are fired on one side and #3 and #4 are fired from the other side of the switch box. If
the trigger tests good by the chart below, but you have two cylinders not firing (either #1 and #2 or #3 and #4), the
switch box or stator is bad.
- If you have two cylinders not firing (either #1 or #2 or #3 and #4), swap the stator leads end to end on the switch box (Red with red/white and blue with blue/white). If the problem moves to the other cylinders, the stator is bad. It the problem stays on the same cylinders, the switch box is likely bad.
- Check the DVA output on the green wires from the switch box while connected to the ignition coils. Check the reading on the switch box terminal AND on the ignition coil terminal. You should have a reading of at least 150V or more at both places. If the reading is low on one cylinder, disconnect the green wire from the ignition coil for that cylinder and reconnect it to a load resistor. Retest. If the reading is now good, the ignition coil is likely bad. A continued low reading indicates a bad power pack.
|
Engine will not rev beyond 3000-4000 RPM:
- Connect an inductive Tachometer to all cylinders and try to isolate the problem. If two cylinders on the same
end of the switch box are dropping out, the problem is likely going to be either the switch box or trigger. A single
cylinder dropping fire will likely be the switch box or ignition coil. All cylinders acting up usually indicate a
bad stator.
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continued next page....
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| Page 23 - Index - Page 25 |
