Just got my '89 back from having the AC repaired (which I started, but couldn't successfully finish). Seeing newly-low readings on the voltage gauge. Reads a nudge above 14V on cold start but eventually drops down to a little above halfway between 9V and 14V.

This one has a full 5-90 wiring kit on it, and the connections seem secure, as do the battery terminals.

Stuck a voltmeter across the battery when warmed up and with high beams, AC and stereo running and get a reading of 13.6V across the terminals, which doesn't seem like a disaster. Looks much lower on the inside gauge, though, and the needle moved noticeably when I switched on each of lights and AC -- but I didn't see the lights dim when switching on AC or other obvious signs of low voltage. Also seems to be idling a little lower than I recall, but couldn't swear to that.

Real issue or something to do with the connections?

 

Solution....http://www.jeepforum.com/forum/f11/r...ge-fix-684375/

 

Thank you freegdr for the great tip. Wow, I've always wondered and worried about that gauge. Even had a digital hooked up to the cig lighter circuit and didn't understand why the variance of the gauge.
I had considered replacing the gauge, but now there is a cure, Thank you!
One note aside, I've gone a little stupid on over lighting, but it sure is great to have with an extraction after dark, and with a digi gauge installed I've seen my volts steadily dropping over time with all systems on. So you can see the limitations of the stock alternator if you over tax the output.

 

Upgrading battery cables will help greatly with power distribution .

 

You're noticing it now that the AC works. Pretty normal.

 

Cool. Thank you. Another project to do

 

Nice. Thanks a lot. Now I'll decide how lazy I am. I have some 4 ga running from the positive terminal to aux fuse box in the cabin, might try running it there first since it'll only be ~3ft.