Posted by Arthur P. Bloom on Saturday, July 07, 2007 at 11:13:22 :
In Reply to: Elect. help!!! posted by Howard in Newcastle on Saturday, July 07, 2007 at 10:44:45 :
We assume that you mean that the engine cranks, but gets no ignition.
The next time it happens, immediately do this:
Open the hood. With a test lamp, or a voltmeter set on DC 0-20 volts, put one test lead on GROUND and the other test lead on the HOT side of the ignition coil. Tell us what the results of this test are.
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To determine which is the HOT side, you must do this before you try the above test:
At the top of the coil, there is the high-tension lead that feeds spark to the distributor, and there are two smaller low-tension leads connected by small nuts.
One of two low-tension leads is IGN (HOT) from the IGN switch, and the other is the GRD lead that is switched by the points within the distributor.
You must disconnect the two low-tension leads, and perform the next test carefully:
The HOT lead will light the test lamp, or cause the DC voltmeter to indicate a voltage, when the IGN switch is turned ON.
((The distributor-to-coil lead will not do this. In the event that you wish to test this lead for any reason (not for this particular test) one of the test lamp or meter leads should be connected to BATT. It will either indicate an OPEN (no ground)when the points are open, and it will indicate a GROUND when the points are closed.))
Mark the IGN lead with something like a small piece of tape. Put all wires back where they were originally fastened.
If you mean that the engine does not crank, we need to do other tests.
How long a time period is the SHORTEST time between successful starts? I am not aware of how the circuit breaker is wired into the truck's system. Perhaps another person can tell us. I would assume that it is to protect against a short or overload in the headlamp circuits, and would not be wired into the IGN circuit. I may be wrong.
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