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Discussion Starter · #1 ·
I've read a lot of the previous posts and can't figure this one out. From time to time, for no apparent reason, the ignition cuts out on farmjeep (77CJ5, 304, stock ignition). If I flip the key forward to start for just a second, it fires right back up. Or if I'm going down the road and the ignition cuts out, but the momentum is keeping the jeep rolling and the engine turning, twisting the key forward momentarily will "restart" the ignition. Does it hot, cold, wet, dry...sometimes only once, sometimes several times in a row, sometimes goes for a week with no problems. I've read a lot of people blaming things on the ignition module...could that be it?

Evolution of tools: stone, hammer, wrench, socket, impact, really big hammer, blue wrench.

· Registered
4,675 Posts
but you dont have the same ign module weve been talking about, you should have that littel gold box on the passenger fender, thats that old BID system I think, maybe it has the same problems, Im not sure..
since it fires back when you touch back to start position, Id bet there is an open in the coil wire somewhere that occasionally opens?
these things are the hardest type of thing to hunt down.

Id say a good time to go the Duraspark route....start fresh, new wires

just my 2cents, overpriced as usual

77 CJ5, in a bunch of sanded and primered pieces

Discussion Starter · #3 ·
That's right, you have the prestolite ignition like I do. They're even more prone to problems. And the module itself is $40 at the cheapest... Go duraspark... Its just a matter of running a few new wires and TR has really good diagrams of the whole thing...

Florida Mud CJ-5
'77 RB304, t-150 D20 4" 35" swampers

· Registered
6,784 Posts
Sounds like it might be carbon on the contacts of the ignition switch also...
I've seen that problem, and it's a real b*tch to track down...
By moving the key, you may be scratching off the carbon just enough to get a connection again, but as soon as you hit a bad spot, or the heat builds up.... dead again....

Here are the diagrams for the permanent wiring harness.
If you need a parts list, let me know...
Someone here should be able to tell you where the Mopar web site is that has the cheap BRAND NEW distributors.... You will need one...

Here is the wiring diagram for a permanent wiring harness.
THIS IF FOR 74 THROUGH 77 ONLY, and should NEVER be done in states where it will defeat factory emissions controls...

1. Power Connector for the DuraSpark unit.
Red Wire is 'Start' or 'Cranking' power to the module. 12 volts during cranking.
Doesn't hurt a thing to be 'Hot' while engine is running.

White Wire is 'Run' power to the module. Must have a full 12 volts while engine is running.

2. Harness Connector for module power wires. (Standard Ignition Parts P/N S-629)
White wire should come from full 12 Volt source through the ignition switch.
Usually can be hooked to the positive side of the coil, BEFORE the resistor.

Red wire can come from Starter solenoid 'I' terminal,
from full 12 volt coil source if it's hot during cranking.

3. Control connector for the DuraSpark Module.
Has four wires.
Green, goes to coil negative.
Black, goes to ground. This is the ONLY GROUND for the module.
Violet, goes to the distributor violet wire.
Orange, goes to the distributor orange wire.

4. Harness Connector For DuraSpark Module Control Wiring.
(Standard Ignition Parts P/N S-698)
I splice into the Module 'Black' wire and direct ground that wire.

5. Factory Distributor Pickup connector.
Motorcraft grounded the DuraSpark module through the distributor. I keep this connection when building a wiring harness, as well as directly grounding the module through a splice in the wiring harness.

6. Harness connector for Distributor. (Ford Dealership is the only place I know to get these)

7. Ignition coil connector. (Standard Ignition Parts P/N S-539 for TFI coil connector, P/N S-583 for round coil connector)

8. Ignition Resistor.
Used just before the Ignition Coil Positive connection.

Ford Resistor Wire, 49" long, (Auto Zone/ Wells P/N F799)
Chrysler Porcelain 'Pot' Type Resistor, (Auto Zone/ Wells P/N CR105)

9. Four Terminal Starter Solenoid.
If you only have a three terminal Starter Solenoid, this wire can be hooked up in the same place as the White wire.
I prefer to do things this way if the solenoid permits.

"I Have The Body Of A God... Buddha"


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