74 CJ5 Electrical Problem

My 74 CJ5 has been doing something strange for the last few weeks. It did it again today. While idling during warm up, it suddenly stopped. No power to the dash, starter, or lights. After checking the battery, which was fully charged, and wiring connections, everything started working. It is as if there is a thermal circut breaker that resets itself. Thanks for any help.

 

While I was shopping for a new "stock" alternator for the CJ, I ran across the following information for some of them:

"INSTALLATION ALERT! This application prone to voltage regulator failure. Follow prescribed test procedure to avoid mis-diagnosing the charging system."

and this one:

"INSTALLATION ALERT! A blown fuse or bulb in the warning lamp circuit may cause a "no charge" condition. Verify that battery voltage is present at terminal "1" of the alternator plug"

???

 

The next time it happens, carefully touch the ignition switch to see if it's hot. Sounds like the switch may be going bad. Other things to check are all of the battery connections, power and ground, at all locations. Take them apart, clean them with a wire brush, and put them back together properly. The battery is prone to building up a black lead oxide on the terminals that will stop current flow dead, but it generally shows up when cranking the starter. A bad ground connection at the firewall and at the engine block is not uncommon.

 

Yes, ignition switch. If that goes bad, you can lose power to the ignition intermittently.

A '74 will have points ignition, so look at all the usual suspects - coil, points, condensor.

Battery problems won't stop the engine from running if the alternator and regulator (charging circuit) are working. If you have plenty of cranking power, I'd expect the charging cuircuit is ok.

This sounds like an ignition problem, and not a fuel problem. However, it would be good to be thorough and look down the carb to check that you have fuel, if it stops again.

 

Years ago my '74 CJ5 did exactly as is being described here. Cleaning the battery terminals fixed the problem!

 

my 74 did the same thing,it would turn off then it wouldn't crank or start ..it was the wire harness the big plug going to firewall on the right side of engine..