[Guest]

Here are the facts: Went Fourwheeling last weekend everything is fine. Tuesday Night Start the Jeep, It runs for about 30 seconds and then cuts out. Unable to restart it. Symptoms: Engine cranks and cranks. Jeep has gas 100% sure, looked in Carb. I figured it was the ignition coil, cap or, rotor. I decided to upgrade plugs, wires, coil, and get new cap and rotor anyway. It now has Jacobs coil and Wires, Bosch Platnium plugs and new rotor and cap. I still have the same problem. Here is what I know: I have a stock distributor. I have 12 volts at the positive side of the coil. I have spark coming form the the coil to the cap, but it is weak. I have spark at the plug wires that is also weak. What I think is the culprit is the stock Electronic Control box mounted on the right fender. The distributor's one wire leads to a wire harness that dumps into this box. Please help. I don't know anything about this box or if it can be bypassed or what. I know someone will suggest I go with a HEI ignition, but I don't have the money, plus I just bought the new Jaccobs Coil. Any insight would be great, I hope to fix this by tomorrow so I can take the Jeep Wheeling on Sunday.

 

[Guest]

Check the pick up coil in the distributor, its about a 25 dollar coil that gave me grief a couple of months ago. If you are using the Prestolite distributor you have to take off the cap, rotor, shield and gently use a wheel puller to pop off the part that has six arms that spins around the coil. I had a problem where the coil had floated over to the side and had been completly worn down by the spinning part (I'm sorry, I just can't think of its name at the moment). The pick up has to be centered between the fingers of each spindle, there is a gage out there to set it usually comes in the replacement kit.

The ignition system is relatively simple, there are only so many parts that can be wrong. You can try pulling the electric ignition module and take it to NAPA, they checked mine for free. Check the wires with an OHM meter to see resistance. Even though you replaced the ignition coil, you might want to check the voltage across the primary and the secondary (Chilton or Haynes gives a good guide on what voltages and how).

The distributor has 2 black wires from the pick up coil that go into a 4 port plug (if this is a prestolite) and the 2 wires from the ignition coil end up there (the other 2 wires). Check the ignition coil wires from the plug to the coil (your wires are 33 years old). That is the system in a nutshell.